TY  - JOUR
A1  - Kühn, Heike
A1  - Schön, Franz
A1  - Edelmann, Karola
A1  - Brill, Stefan
A1  - Müller, Joachim
T1  - The Development of Lateralization Abilities in Children with Bilateral Cochlear Implants
JF  - ORL
N2  - Objectives: The purpose of this study was to investigate the development of lateralization skills in children who received bilateral cochlear implants (CIs) in sequential operations. Methods: The lateralization skills of 9 children with a mean age of 4.1 years at the first surgery and 5.5 years at the second surgery were assessed at 3 time intervals. Children were assessed with a 3-loudspeaker setup (front, left and right) at 0.9 years (interval I) and 1.6 years (interval II) after the second implantation, and after 5.3 years of bilateral implant use (interval III) with a 9-loudspeaker setup in the frontal horizontal plane between -90° and 90° azimuth. Results: With bilateral implants, a significant decrease in lateralization error was noted between test interval I (45.0°) and II (23.3°), with a subsequent significant decrease at test interval III (4.7°). Unilateral performance with the CI did not improve significantly between the first 2 intervals; however, there was a bias of responses towards the unilateral side by test interval III. Conclusions: The lateralization abilities of children with bilateral CIs develop in a relatively short period of time (1-2 years) after the second implant. Children appear to be able to acquire binaural skills after bilateral cochlear implantation.
KW  - localization
KW  - bilateral cochlear implant
KW  - children
KW  - MED-EL cochlear implant
KW  - lateralization
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196375
SN  - 0301-1569
SN  - 1423-0275
N1  - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
VL  - 75
IS  - 2
ER  - 
TY  - THES
A1  - Müller, Heike Milada
T1  - Anpassung an Trocken- und Salzstress: Untersuchungen an Modellpflanzen und Extremophilen
T1  - Adaptation to drought and salt stress: studies on model plants and extremophiles
N2  - Die wahrscheinlich größten Probleme des 21. Jahrhunderts sind der Klimawandel und die Sicherstellung der Nahrungsmittelversorgung für eine steigende Zahl an Menschen. Durch die Zunahme von extremen Wetterbedingungen wie Trockenheit und Hitze wird der Anbau konventioneller, wenig toleranter Nutzpflanzen erschwert und die dadurch notwendige, steigende Bewässerung der Flächen führt darüber hinaus zu einer zusätzlichen Versalzung der Böden mit für Pflanzen toxischen Natrium- und Chlorid-Ionen. Kenntnisse über Anpassungsstrategien salztoleranter Pflanzen an Salzstress, aber auch detailliertes Wissen über die Steuerung der Transpiration und damit des Wasserverlusts von Pflanzen sind daher wichtig, um auch künftig ertragreiche Landwirtschaft betreiben zu können. In dieser Arbeit habe ich verschiedene Aspekte der pflanzlichen Stressphysiologie bearbeitet, die im Folgenden getrennt voneinander zusammengefasst werden. 
I. Funktionelle Unterschiede der PYR/PYL-Rezeptoren von Schließzellen 
Entscheidend für den Wasserstatus von Pflanzen ist die Kontrolle des Wasserverlusts durch Spaltöffnungen (Stomata), die von einem Paar Schließzellen gebildet werden. Externe Faktoren wie Licht, Luftfeuchtigkeit und CO2, sowie interne Faktoren wie das Phytohormon Abszisinsäure (ABA) regulieren über Signalkaskaden die Stomaweite und dadurch den Wasserverlust. Die zugrunde liegenden Signalkaskaden überlappen teilweise. Vor allem der Stomaschluss durch erhöhtes CO2 und ABA weisen viele Gemeinsamkeiten auf und die Identifizierung des Konvergenzpunktes beider Signale ist immer noch aktueller Gegenstand der Forschung. Von besonderem Interesse sind dabei die in Schließzellen exprimierten ABA-Rezeptoren der PYR/PYL-Familie. Denn obwohl bislang nicht nachgewiesen werden konnte, dass CO2 zu einem Anstieg des ABA-Gehalts von Schließzellen führt deuten einige Studien darauf hin, dass die ABA-Rezeptoren selbst am CO2-Signalweg beteiligt sind. 
Durch Untersuchungen der Stomareaktion von Arabidopsis ABA-Rezeptormutanten konnte ich in dieser Arbeit zeigen, dass die in Schließzellen exprimierten ABA-Rezeptoren der PYR/PYL-Familie funktionale Unterschiede aufweisen. Fünffach-Verlustmutanten der ABA-Rezeptoren PYR1, PYL2, 4, 5 und 8 (12458) waren in ihrem ABA-induzierten Stomaschluss beeinträchtigt und nur die Komplementation mit PYL2 und in geringerem Maße PYR1 konnte die ABA-Sensitivität wiederherstellen. Die Stomata von 12458-Verlustmutanten waren außerdem insensitiv gegenüber erhöhtem CO2, was auf eine Beteiligung der ABA-Rezeptoren am CO2-induzierten Stomaschluss hindeutet und diese Sensitivität konnte nur durch die Komplementation mit PYL4 oder PYL5, nicht aber mit PYL2 wiederhergestellt werden. Somit konnten in dieser Arbeit erstmals funktionelle Unterschiede der PYR/PYLs beim Stoma-Schluss nachgewiesen werden.
Alle externen und internen Stomaschluss-Signale haben außerdem Einfluss auf die Genexpression der Schließzellen und führen zu individuellen expressionellen Adaptionen. In vorangegangenen Microarray Studien konnte gezeigt werden, dass jeder Stimulus auch die Expression eines distinkten Sets an ABA-Rezeptoren beeinflusst. Im Rahmen dieser Arbeit konnte ich außerdem zeigen, dass die Expression der ABA-Rezeptoren bereits auf kleine Änderungen der ABA-Konzentration der Schließzellen reagiert und dass diese sich außerdem in ihrer Sensitivität gegenüber ABA unterschieden. Geringe Änderungen der ABA-Konzentration von Schließzellen haben demnach Auswirkungen auf deren Rezeptor-zusammensetzung. Darüber hinaus konnte ich zeigen, dass die Rezeptoren die Expression unterschiedlicher nachgeschalteter Gene beeinflussen, was darauf hindeutet, dass Anpassungen des Rezeptorpools durch geringe Änderungen des ABA-Gehalts von Schließzellen schlussendlich auf genexpressioneller Ebene zur längerfristigen Adaption an externe Bedingungen führen und die Rezeptoren auch hier funktional verschieden sind. 
II. Stomatäre Besonderheiten der toleranten Dattelpalme (Phoenix dactylifera)
Dattelpalmen kommen natürlicherweise an besonders trockenen und heißen Standorten vor, an denen es aufgrund der harschen Bedingungen nur sehr wenigen Pflanzen möglich ist überhaupt zu wachsen. Ein naheliegender Grund für die herausragende Toleranz dieser Art gegenüber wasserlimitierenden Bedingungen ist eine Anpassung der stomatären Regulation zu Gunsten des Wasserhaushalts. 
In dieser Arbeit konnte ich durch vergleichende Untersuchungen der lichtabhängigen Transpiration sowie dem ABA-induzierten Stomaschluss grundlegende Unterschiede in der Stomaphysiologie der Dattelpalmen und der eher sensitiven Modellpflanze Arabidopsis thaliana nachweisen. Blattgaswechselmessungen zeigten, dass Dattelpalmen in der Lage sind die Spaltöffnungen bei niedrigen Lichtintensitäten, bei denen Arabidopsis bereits deutlich geöffnete Stomata aufwies, geschlossen zu halten. Der bedeutendste Unterschied in der Stomaphysiologie von Dattelpalmen und Arabidopsis lag aber im ABA-induzierten Stomaschluss. Während über die Petiole verabreichtes ABA bei Arabidopsis innerhalb von 15 Minuten zu einem vollständigen Stomaschluss führte, konnte ich in dieser Arbeit zeigen, dass der ABA-induzierte Stomaschluss der Datteln nitratabhängig ist. ABA allein führte nur zu einem sehr langsamen Stomaschluss der innerhalb einer Stunde nicht vollständig abgeschlossen war. Nur in Gegenwart von Nitrat führte die ABA-Gabe in den Transpirationsstrom der Fiederblätter der Datteln zu einem schnellen und vollständigen Stomaschluss. In Arabidopsis wird der in Schließzellen vorkommende Anionenkanal AtSLAC1 durch eine über den ABA-Signalweg vermittelte Phosphorylierung aktiviert, was schlussendlich zur Aktivierung spannungsabhängiger Kationenkanäle und zum Ausstrom von Kalium aus den Schließzellen führt. Es konnte gezeigt werden, dass die Nitratabhängigkeit der ABA-Antwort der Schließzellen von Dattelpalmen auf Eigenschaften von PdSLAC1 zurückzuführen ist und dieser Kanal nur in Anwesenheit von extrazellulärem Nitrat aktivierbar ist. Mittlerweile konnte, unter anderem basierend auf diesen Ergebnissen, eine Tandem-Aminosäuresequenz identifiziert werden, die die SLAC-Homologe monokotyler Pflanzen wie der Dattelpalme von der dikotyler Pflanzen unterscheidet und zumindest teilweise für die nitratabhängige Aktivierung des Stomaschlusses vieler monokotyler verantwortlich ist.
III. Die Salztoleranz von Phoenix dactylifera und Chenopodium quinoa
Sowohl Dattelpalmen als auch C. quinoa weisen, verglichen mit den meisten anderen Pflanzen, eine hohe Toleranz gegenüber NaCl-haltigen Böden auf. In dieser Arbeit habe ich die Salztoleranz beider Arten untersucht, um so Strategien zu identifizieren, die diesen Pflanzen diese gesteigerte Toleranz ermöglichen.
Dattelpalmen können natürlicherweise auf salzigen Böden wachsen. Makroskopisch weisen diese Pflanzen aber keine Anpassungen wie bspw. Salzdrüsen auf und bislang ist unklar wie Dattelpalmen mit dem NaCl aus dem Boden umgehen. In dieser Arbeit konnte ich zeigen, dass der Natriumgehalt der Fiederblätter der Datteln durch eine sechswöchige Bewässerung mit 600mM NaCl, was ungefähr der Konzentration von Meerwasser entspricht, nicht zunimmt. Demnach sind Datteln so genannte „Exkluder“, also Pflanzen, die eine übermäßige Natriumaufnahme in photosynthetisch aktives Gewebe vermeiden. Der Natriumgehalt der Wurzeln dagegen nahm unter Salzstress aber zu. Diese Zunahme war allerdings in unterschiedlichen Bereichen der Wurzeln verschieden stark. Flammenphotometrische Messungen ergaben einen vom Wurzelansatz ausgehenden graduellen Anstieg des Natriumgehalts, der an der Wurzelspitze am höchsten war. Darüber hinaus konnte eine Induktion von PdSOS1, einem putativen Na+/H+-Antiporter in diesen unteren, natriumhaltigen Bereichen nachgewiesen werden. Eine hohe SOS1-Aktivität gilt bereits in anderen toleranten Arten als Schlüsselmerkmal für deren Toleranz und die gesteigerte Expression von PdSOS1 deutet auf eine erhöhte Natrium-Exportrate aus der Wurzel zurück in den Boden in diesen unteren Bereichen hin, was schlussendlich den Ausschluss von Natrium vermitteln könnte.
In sensitiven Arten führt Salzstress häufig zu einer Abnahme der Kaliumkonzentration des Gewebes. Interessanterweise war dies weder für das Blatt- noch das Wurzelgewebe der Dattelpalmen der Fall. Der Kaliumgehalt beider Gewebe blieb trotz der Bewässerung der Pflanzen mit Salzwasser konstant. Auf expressioneller Ebene konnte ich darüber hinaus zeigen, dass PdHAK5, ein putativer hochaffiner Kaliumtransporter, der unter Kontrollbedingungen überwiegend in den oberen Wurzelabschnitten exprimiert wurde, durch den Salzstress dort reprimiert wurde. PdKT, ebenfalls ein putatives Kalium-Transportprotein dagegen, wurde nicht durch die Salzbehandlung beeinflusst, was zusammengenommen darauf hindeutet, dass das Aufrechterhalten des Kaliumgehalts bei Salzstress durch die differentielle Regulation verschiedener Kaliumaufnahmesysteme gewährleistet wird. Der effiziente Ausschluss von Natrium zusammen mit dem hohen K+/Na+-Verhältnis könnten demnach Schlüsselmerkmale für die hohe Salztoleranz von Phoenix dactylifera darstellen. 
Quinoa ist, ähnlich wie die Dattelpalme, eine salztolerante Nutzpflanze. Im Gegensatz zu Dattelpalmen weist Quinoa allerdings besondere Strukturen auf der Epidermis auf, die so genannten epidermalen Blasenhaare (englisch: epidermal bladder cells, EBCs). Die Funktion dieser ballonartig vergrößerten Zellen als externe Salzspeicher wird seit längerem diskutiert.
Flammenphotometrische Messungen des Natriumgehalts von Quinoa unter Salzstressbedingungen ergaben, dass Quinoa anders als Dattelpalmen, Natrium in die oberirdischen, photosynthetisch aktiven Organe aufnimmt. Auch die Zunahme des Natriumgehalts der EBCs konnte ich nachweisen. Junge Blätter haben eine hohe Dichte an intakten EBCs, was deren Funktion als externe Salzspeicher besonders zum Schutz dieser jungen Blätter nahelegt. mRNA-Sequenzierungen ergaben darüber hinaus, dass die EBCs bereits unter Kontrollbedingungen viele in grundlegende Stoffwechselprozesse involvierte Gene sowie membranständige Transportproteine differentiell exprimieren. Diese Unterschiede im Transkriptom der EBCs zum Blattgewebe zeigen, dass katabole Stoffwechselwege nur eine untergeordnete Rolle in den hochspezialisierten EBCs spielen und deren Stoffwechsel auf dem Import energiereicher Zucker und Aminosäuren basiert.
Mittels qPCR-Messungen und RNA-Sequenzierungen konnte ich die gewebespezifische Expression verschiedener Transportproteine nachweisen, die eine gerichtete Aufnahme von Natrium in EBCs ermöglichen könnten. Besonders die differentielle Expression eines Natriumkanals der HKT1-Familie deutet auf dessen Beteiligung an der Natriumbeladung der EBCs hin. CqHKT1.2 wurde ausschließlich in EBCs exprimiert und die elektrophysiologische Charakterisierung dieses Transportproteins ergab eine spannungsabhängige Natriumleitfähigkeit. Dieser Natriumkanal kann demnach die Natriumaufnahme bei Membranspannungen nahe dem Ruhepotential in die EBCs vermitteln und die Deaktivierung des CqHKT1.2 bei depolarisierenden Membranspannungen kann darüber hinaus einen Efflux von Na+ aus den EBCs verhindern. Auch das Expressionsmuster eines putativen Na+/H+-Antiporters (CqSOS1) der nur sehr gering in EBCs aber deutlich höher in Blattgewebe exprimiert wurde, deutet auf eine indirekte Beteiligung dieses SOS1 an der Beladung der EBCs hin. Bereits charakterisierte SOS1-Proteine anderer Pflanzen zeigten unter physiologischen Bedingungen eine Natriumexport-Aktivität. CqSOS1 könnte demnach den Export von Natrium aus Mesophyll- und Epidermiszellen der Blätter in den Apoplasten vermitteln, welches dann über CqHKT1.2 in die EBCs aufgenommen wird. 
Trotz der Natriumaufnahme in die oberirdischen Teile und die EBCs führte die Salzbehandlung ähnlich wie bei den Datteln nicht zu einer Abnahme des bemerkenswert hohen Kaliumgehalts. Mittels qPCR-Untersuchungen konnte ich die Expression verschiedener HAK-Orthologe nachweisen, deren Aktivität die Aufrechterhaltung des Kaliumgehalts unter Salzstress vermitteln könnten. Frühere Studien konnten zeigen, dass Salzstress bei Quinoa wie bei vielen salztoleranten Arten zu einem Anstieg der Konzentration von kompatiblen gelösten Substanzen und besonders von Prolin führt. In dieser Arbeit konnte ich die hohe Expression eines Prolintransporters in EBCs nachweisen, was eher auf einen importbasierten Anstieg der Prolinkonzentration als auf die Synthese innerhalb der EBCs schließen lässt. 
Zusammengefasst ergaben der Anstieg des Natriumgehalts der EBCs in Verbindung mit den Ergebnissen der RNA-Sequenzierung und den ergänzenden qPCR Messungen, dass die EBCs von Quinoa bereits unter Kontrollbedingen für die Aufnahme von überschüssigen Ionen unter Salzstress spezialisierte Zellen sind, deren Spezialisierung auf dem Import von energiereichreichen Zucken und anderen Substanzen basiert.
N2  - The greatest problem faced by the 21st century are climate change and maintaining the food security for an increasing number of people. The increase in extreme weather events, such as drought and heat, makes it difficult to cultivate conventional crops that are not stress tolerant. As a result, increasing irrigation of arable land leads to additional salinization of soils with plant-toxic sodium and chloride ions. Knowledge about the adaptation strategies of salt-tolerant plants to salt stress as well as detailed knowledge about the control of transpiration and thus of the water loss of these plants are therefore important in order to be able to guarantee productive agriculture in the future. In this work, I have worked on various aspects of plant stress physiology, which will be summarized separately below.
I. Functional differences of guard cell PYR / PYL receptors 
A tight regulation of the transpirational water loss through stomata, which are formed by a pair of guard cells, is crucial for regulating the water status of plants. External factors such as light, humidity and CO2 as well as internal factors such as the phytohormone ABA regulate the stoma width and thus the loss of water via individual signal cascades. However, the underlying signaling cascades partly overlap. In particular, the cascades involved in stomatal closure due to increasing CO2 and ABA overlap and the identification of a convergence point of both signals is still the subject of ongoing research. In this context, the ABA receptors of the PYR/PYL family that are expressed in guard cells are of particular interest. Although it has not yet been demonstrated that CO2 leads to an increase in the ABA content of guard cells, some studies indicate that the ABA receptors themselves are involved in the CO2 signaling pathway
By studying the stomatal response of Arabidopsis ABA receptor mutants, I demonstrated that the PYR / PYL family ABA receptors expressed in guard cells show functional differences. Pentuple knock out mutants of the ABA receptors PYR1, PYL2, 4, 5, and 8 (12458) showed impairment in ABA-induced stomatal closure, and only complementation with PYL2 and, to a lesser extent, PYR1 could restore ABA sensitivity. Additionally, the stomata of the 12458 knockout mutants were also insensitive to elevated CO2 and the sensitivity could only be restored be the complementation with the receptors PYL4 and PYL5 suggesting an involvement of the ABA receptors in the CO2-induced stomatal closure.
Furthermore, all external and internal stimuli that lead to stomatal closure influence the gene expression of guard cells leading to individual adaptions on the gene expression level. Previous microarray studies have shown that each stimulus also affects the expression of a distinct set of ABA receptors. In this work, I showed that the expression of ABA receptors already responded to small changes in the ABA concentration of guard cells and that the receptor expression also differed in their sensitivity to ABA. Small changes in the ABA concentration of guard cells could therefore influence their receptor composition. In addition, I was able to show that the receptors affect the expression of different downstream genes, suggesting that adjustments of the receptor pool by small changes in the ABA content of guard cells ultimately lead to long-term adaptations to external conditions at the gene expression level.
II. Specific features of the stomata of the extremely tolerant date palm (Phoenix dactylifera)
Date palms naturally occur in particularly dry and hot locations, where due to the harsh conditions only very few plant species are able to grow at all. One possible reason for the outstanding tolerance of this species to water-limiting conditions is an adaptation of the stomatal regulation in favor of maintaining water balance.
In this work, I was able to demonstrate fundamental differences in the stomatal physiology of date palm and the rather sensitive model plant Arabidopsis thaliana by comparative studies of light-dependent transpiration and ABA-induced stoma closure. Leaf gas exchange measurements showed that date palm can keep the stomata closed at low light intensities, where Arabidopsis already had clearly opened stomata. However, the most significant difference in the stomatal physiology between date palm and Arabidopsis was found in the ABA-induced stomatal closure. While ABA fed via the petiole resulted in complete stomatal closure within 15 minutes in Arabidopsis, I showed that ABA-induced stomatal closure is nitrate-dependent in date palm. ABA alone only resulted in a very slow stomatal closure that was not fully completed within one hour. Only in the presence of nitrate did the feeding of ABA into the transpiration stream of date palm pinates lead to a rapid and complete stomatal closure. In Arabidopsis, the guard cell-expressed anion channel AtSLAC1 is activated by ABA signaling-mediated phosphorylation, triggering voltage-dependent cation channels to open and ultimately channeling potassium out of the guard cells. It could be shown that the nitrate dependence of the ABA response of the date palm guard cells is due to properties of PdSLAC1 and that this channel can only be activated in the presence of extracellular nitrate. Based on these results, a tandem amino acid sequence has now been identified, that distinguishes the SLAC homologues of monocotyledonous plants (including date palm) from dicotyledonous plants (including Arabidopsis) and is at least partially responsible for the nitrate-dependent activation of the stoma conductance of many monocots.


III. The strategies behind the salt tolerance of P. dactylifera and Chenopodium quinoa
Both date palms and C. quinoa have a high tolerance to NaCl-containing soils compared to most other plant species. In this work, I studied the salt tolerance of both species to identify strategies that allow these plants to grow under salt stress conditions.
Date palm naturally grows on saline soils along the coast of the Arabian Peninsula. However, they do not possess any macroscopic adaptations such as salt glands. So far it is unclear how date palms handle excessive NaCl from the soil. In this work, I was able to show that the sodium content of date palm pinates does not increase after a six-week irrigation with 600mM NaCl, which is roughly the concentration of seawater. Accordingly, date palm is a so-called "excluder", i.e. a plant that avoids excessive sodium uptake into photosynthetically-active tissue. The sodium content of roots, however, increased under salt stress. But this increase was different in different areas of the roots. Flame photometric measurements revealed a gradual increase in sodium content from upper to lower parts of the roots, which was highest at the root tip. In addition, induction of PdSOS1, a putative Na+/H+ antiporter in these lower sodium-containing regions has been demonstrated. High SOS1 activity is already considered to be a key feature of tolerance in other species, and increased expression of PdSOS1 indicates increased sodium export rates from the root back into the soil in these lower areas, which could ultimately mediate the exclusion of sodium.
In sensitive plant species, salt stress often leads to a decrease in the potassium concentration of the tissue. Interestingly, this was not the case for date palm leaf or root tissue. The potassium content of both tissues remained constant despite irrigation of the plants with salt water. On the expression level, I also showed that PdHAK5, a putative high-affinity potassium transporter predominantly expressed in the upper root sections under control conditions, was repressed by the salt stress there. In contrast, PdKT, also a putative potassium transport protein, was not affected by the salt treatment, suggesting that maintenance of potassium content in salt stress is ensured by the differential regulation of various potassium uptake systems. The efficient exclusion of sodium together with the high K+/Na+ ratio could therefore be key features of the high salt tolerance of Phoenix dactylifera.
Quinoa, like the date palm, is a salt-tolerant crop but in contrast to date palms quinoa has special structures on the epidermis, the so-called epidermal bladder cells (EBCs). The function of these balloon-like enlarged cells as external salt dumpers has been proposed.
Flame photometric measurements of the sodium content of quinoa under salt stress conditions showed that quinoa, unlike date palm, absorbs sodium in the above-ground, photosynthetically active parts. I was also able to prove the increase in the sodium content of the EBCs. Young leaves are equipped with a high density of intact EBCs, suggesting their function as external salt stores, especially for the protection of these young leaves. In addition, mRNA sequencing revealed that the EBCs, already under control conditions, differentially express many genes involved in basic metabolic processes as well as membrane-bound transport proteins. These differences in the transcriptome of EBCs to leaf tissue show that catabolic pathways such as photosynthesis play only a minor role in the highly specialized EBCs and their metabolism is based on the import of high energy compounds such as sugars or amino acids.
Using qPCR measurements and RNA sequencing, I was able to demonstrate the tissue-specific expression of various transport proteins, which could allow unidirectional uptake of sodium in EBCs. In particular, the differential expression of a sodium channel of the HKT1 family indicates its involvement in the sodium loading of the EBCs. CqHKT1.2 was expressed exclusively in EBCs and the electrophysiological characterization of this transport protein revealed a voltage-dependent sodium conductivity. Thus, this sodium channel can mediate sodium uptake into EBCs at normal membrane voltages, and deactivation of CqHKT1.2 at depolarized membrane voltages can prevent efflux of Na+ out of the EBCs. The expression pattern of a putative Na+/H+ antiporter (CqSOS1), which is expressed only very low in EBCs but significantly higher in leaf tissue, indicates an indirect involvement of this SOS1 in the loading of the EBCs. SOS1 proteins from other plant species that have already been characterized showed a sodium export activity under physiological conditions. Thus, CqSOS1 could mediate the export of sodium from mesophyll and epidermis cells of the leaves in the apoplasts, which is then absorbed into the EBCs via CqHKT1.2. Similar to the results of date palm, the sodium uptake into the above ground parts and the EBCs of quinoa during the salt treatment did not lead to a decrease in the remarkably high potassium content of quinoa. Using qPCR studies, I was able to demonstrate the expression of various HAK orthologues, the activity of which could mediate the maintenance of potassium levels under salt stress. Previous studies have shown that salt stress in quinoa, as in many tolerant species, leads to an increase in the concentration of compatible solutes and particularly proline. In this work, I was able to demonstrate the high expression of a proline transporter in EBCs, suggesting an import-based increase in proline concentration rather than synthesis within the EBCs. 
In summary, the increase in sodium in EBCs together with the RNA-Seq analyses and the complementary qPCR measurements revealed that the Quinoa EBCs under control conditions are already equipped for the uptake of excess ions under salt stress, with a metabolism that strongly depends on the import of high-energy compounds such as sugars and amino acids.
KW  - Botanik
KW  - Salzresistenz
KW  - Dürreresistenz
KW  - abiotische Stresstoleranz von Pflanzen
KW  - abiotic stress tolerance of plants
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-179005
ER  - 
TY  - JOUR
A1  - Davis, Lea K.
A1  - Yu, Dongmei
A1  - Keenan, Clare L.
A1  - Gamazon, Eric R.
A1  - Konkashbaev, Anuar I.
A1  - Derks, Eske M.
A1  - Neale, Benjamin M.
A1  - Yang, Jian
A1  - Lee, S. Hong
A1  - Evans, Patrick
A1  - Barr, Cathy L.
A1  - Bellodi, Laura
A1  - Benarroch, Fortu
A1  - Berrio, Gabriel Bedoya
A1  - Bienvenu, Oscar J.
A1  - Bloch, Michael H.
A1  - Blom, Rianne M.
A1  - Bruun, Ruth D.
A1  - Budman, Cathy L.
A1  - Camarena, Beatriz
A1  - Campbell, Desmond
A1  - Cappi, Carolina
A1  - Cardona Silgado, Julio C.
A1  - Cath, Danielle C.
A1  - Cavallini, Maria C.
A1  - Chavira, Denise A.
A1  - Chouinard, Sylvian
A1  - Conti, David V.
A1  - Cook, Edwin H.
A1  - Coric, Vladimir
A1  - Cullen, Bernadette A.
A1  - Deforce, Dieter
A1  - Delorme, Richard
A1  - Dion, Yves
A1  - Edlund, Christopher K.
A1  - Egberts, Karin
A1  - Falkai, Peter
A1  - Fernandez, Thomas V.
A1  - Gallagher, Patience J.
A1  - Garrido, Helena
A1  - Geller, Daniel
A1  - Girard, Simon L.
A1  - Grabe, Hans J.
A1  - Grados, Marco A.
A1  - Greenberg, Benjamin D.
A1  - Gross-Tsur, Varda
A1  - Haddad, Stephen
A1  - Heiman, Gary A.
A1  - Hemmings, Sian M. J.
A1  - Hounie, Ana G.
A1  - Illmann, Cornelia
A1  - Jankovic, Joseph
A1  - Jenike, Micheal A.
A1  - Kennedy, James L.
A1  - King, Robert A.
A1  - Kremeyer, Barbara
A1  - Kurlan, Roger
A1  - Lanzagorta, Nuria
A1  - Leboyer, Marion
A1  - Leckman, James F.
A1  - Lennertz, Leonhard
A1  - Liu, Chunyu
A1  - Lochner, Christine
A1  - Lowe, Thomas L.
A1  - Macciardi, Fabio
A1  - McCracken, James T.
A1  - McGrath, Lauren M.
A1  - Restrepo, Sandra C. Mesa
A1  - Moessner, Rainald
A1  - Morgan, Jubel
A1  - Muller, Heike
A1  - Murphy, Dennis L.
A1  - Naarden, Allan L.
A1  - Ochoa, William Cornejo
A1  - Ophoff, Roel A.
A1  - Osiecki, Lisa
A1  - Pakstis, Andrew J.
A1  - Pato, Michele T.
A1  - Pato, Carlos N.
A1  - Piacentini, John
A1  - Pittenger, Christopher
A1  - Pollak, Yehunda
A1  - Rauch, Scott L.
A1  - Renner, Tobias J.
A1  - Reus, Victor I.
A1  - Richter, Margaret A.
A1  - Riddle, Mark A.
A1  - Robertson, Mary M.
A1  - Romero, Roxana
A1  - Rosàrio, Maria C.
A1  - Rosenberg, David
A1  - Rouleau, Guy A.
A1  - Ruhrmann, Stephan
A1  - Ruiz-Linares, Andreas
A1  - Sampaio, Aline S.
A1  - Samuels, Jack
A1  - Sandor, Paul
A1  - Sheppard, Broke
A1  - Singer, Harvey S.
A1  - Smit, Jan H.
A1  - Stein, Dan J.
A1  - Strengman, E.
A1  - Tischfield, Jay A.
A1  - Valencia Duarte, Ana V.
A1  - Vallada, Homero
A1  - Van Nieuwerburgh, Flip
A1  - Veenstra-VanderWeele, Jeremy
A1  - Walitza, Susanne
A1  - Wang, Ying
A1  - Wendland, Jens R.
A1  - Westenberg, Herman G. M.
A1  - Shugart, Yin Yao
A1  - Miguel, Euripedes C.
A1  - McMahon, William
A1  - Wagner, Michael
A1  - Nicolini, Humberto
A1  - Posthuma, Danielle
A1  - Hanna, Gregory L.
A1  - Heutink, Peter
A1  - Denys, Damiaan
A1  - Arnold, Paul D.
A1  - Oostra, Ben A.
A1  - Nestadt, Gerald
A1  - Freimer, Nelson B.
A1  - Pauls, David L.
A1  - Wray, Naomi R.
A1  - Stewart, S. Evelyn
A1  - Mathews, Carol A.
A1  - Knowles, James A.
A1  - Cox, Nancy J.
A1  - Scharf, Jeremiah M.
T1  - Partitioning the Heritability of Tourette Syndrome and Obsessive Compulsive Disorder Reveals Differences in Genetic Architecture
JF  - PLoS Genetics
N2  - The direct estimation of heritability from genome-wide common variant data as implemented in the program Genome-wide Complex Trait Analysis (GCTA) has provided a means to quantify heritability attributable to all interrogated variants. We have quantified the variance in liability to disease explained by all SNPs for two phenotypically-related neurobehavioral disorders, obsessive-compulsive disorder (OCD) and Tourette Syndrome (TS), using GCTA. Our analysis yielded a heritability point estimate of 0.58 (se = 0.09, p = 5.64e-12) for TS, and 0.37 (se = 0.07, p = 1.5e-07) for OCD. In addition, we conducted multiple genomic partitioning analyses to identify genomic elements that concentrate this heritability. We examined genomic architectures of TS and OCD by chromosome, MAF bin, and functional annotations. In addition, we assessed heritability for early onset and adult onset OCD. Among other notable results, we found that SNPs with a minor allele frequency of less than 5% accounted for 21% of the TS heritability and 0% of the OCD heritability. Additionally, we identified a significant contribution to TS and OCD heritability by variants significantly associated with gene expression in two regions of the brain (parietal cortex and cerebellum) for which we had available expression quantitative trait loci (eQTLs). Finally we analyzed the genetic correlation between TS and OCD, revealing a genetic correlation of 0.41 (se = 0.15, p = 0.002). These results are very close to previous heritability estimates for TS and OCD based on twin and family studies, suggesting that very little, if any, heritability is truly missing (i.e., unassayed) from TS and OCD GWAS studies of common variation. The results also indicate that there is some genetic overlap between these two phenotypically-related neuropsychiatric disorders, but suggest that the two disorders have distinct genetic architectures.
KW  - TIC disorders
KW  - missing heritability
KW  - complex diseases
KW  - neuropsychiatric disorders
KW  - common SNPS
KW  - gilles
KW  - family
KW  - brain
KW  - expression
KW  - autism
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-127377
SN  - 1553-7390
VL  - 9
IS  - 10
ER  - 
TY  - JOUR
A1  - Biju, Joseph
A1  - Schwarz, Roland
A1  - Linke, Burkhard
A1  - Blom, Jochen
A1  - Becker, Anke
A1  - Claus, Heike
A1  - Goesmann, Alexander
A1  - Frosch, Matthias
A1  - Müller, Tobias
A1  - Vogel, Ulrich
A1  - Schoen, Christoph
T1  - Virulence Evolution of the Human Pathogen Neisseria meningitidis by Recombination in the Core and Accessory Genome
JF  - PLoS One
N2  - Background
Neisseria meningitidis is a naturally transformable, facultative pathogen colonizing the human nasopharynx. Here, we analyze on a genome-wide level the impact of recombination on gene-complement diversity and virulence evolution in N. meningitidis. We combined comparative genome hybridization using microarrays (mCGH) and multilocus sequence typing (MLST) of 29 meningococcal isolates with computational comparison of a subset of seven meningococcal genome sequences.

Principal Findings
We found that lateral gene transfer of minimal mobile elements as well as prophages are major forces shaping meningococcal population structure. Extensive gene content comparison revealed novel associations of virulence with genetic elements besides the recently discovered meningococcal disease associated (MDA) island. In particular, we identified an association of virulence with a recently described canonical genomic island termed IHT-E and a differential distribution of genes encoding RTX toxin- and two-partner secretion systems among hyperinvasive and non-hyperinvasive lineages. By computationally screening also the core genome for signs of recombination, we provided evidence that about 40% of the meningococcal core genes are affected by recombination primarily within metabolic genes as well as genes involved in DNA replication and repair. By comparison with the results of previous mCGH studies, our data indicated that genetic structuring as revealed by mCGH is stable over time and highly similar for isolates from different geographic origins.

Conclusions
Recombination comprising lateral transfer of entire genes as well as homologous intragenic recombination has a profound impact on meningococcal population structure and genome composition. Our data support the hypothesis that meningococcal virulence is polygenic in nature and that differences in metabolism might contribute to virulence.
KW  - population genetics
KW  - DNA recombination
KW  - meningococcal disease
KW  - recombinant proteins
KW  - genomic databases
KW  - comparative genomics
KW  - neisseria meningitidis
KW  - homologous recombination
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137960
VL  - 6
IS  - 4
ER  - 
TY  - JOUR
A1  - Chatterjee, Manik
A1  - Andrulis, Mindaugas
A1  - Stühmer, Thorsten
A1  - Müller, Elisabeth
A1  - Hofmann, Claudia
A1  - Steinbrunn, Torsten
A1  - Heimberger, Tanja
A1  - Schraud, Heike
A1  - Kressmann, Stefanie
A1  - Einsele, Hermann
A1  - Bargou, Ralf C.
T1  - The PI3K/Akt signaling pathway regulates the expression of Hsp70, which critically contributes to Hsp90-chaperone function and tumor cell survival in multiple myeloma
JF  - Haematologica
N2  - Despite therapeutic advances multiple myeloma remains largely incurable, and novel therapeutic concepts are needed. The Hsp90-chaperone is a reasonable therapeutic target, because it maintains oncogenic signaling of multiple deregulated pathways. However, in contrast to promising pre-clinical results, only limited clinical efficacy has been achieved through pharmacological Hsp90 inhibition. Because Hsp70 has been described to interact functionally with the Hsp90-complex, we analyzed the suitability of Hsp72 and Hsp73 as potential additional target sites. Expression of Hsp72 and Hsp73 in myeloma cells was analyzed by immunohistochemical staining and western blotting. Short interfering RNA-mediated knockdown or pharmacological inhibition of Hsp72 and Hsp73 was performed to evaluate the role of these proteins in myeloma cell survival and for Hsp90-chaperone function. Furthermore, the role of PI3K-dependent signaling in constitutive and inducible Hsp70 expression was investigated using short interfering RNA-mediated and pharmacological PI3K inhibition. Hsp72 and Hsp73 were frequently overexpressed in multiple myeloma. Knockdown of Hsp72 and/or Hsp73 or treatment with VER-155008 induced apoptosis of myeloma cells. Hsp72/Hsp73 inhibition decreased protein levels of Hsp90-chaperone clients affecting multiple oncogenic signaling pathways, and acted synergistically with the Hsp90 inhibitor NVP-AUY922 in the induction of death of myeloma cells. Inhibition of the PI3K/Akt/GSK3b pathway with short interfering RNA or PI103 decreased expression of the heat shock transcription factor 1 and down-regulated constitutive and inducible Hsp70 expression. Treatment of myeloma cells with a combination of NVP-AUY922 and PI103 resulted in additive to synergistic cytotoxicity. In conclusion, Hsp72 and Hsp73 sustain Hsp90-haperone function and critically contribute to the survival of myeloma cells. Translation of Hsp70 inhibition into the clinic is therefore highly desirable. Treatment with PI3K inhibitors might represent an alternative therapeutic strategy to target Hsp70.
KW  - Haematology
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130574
VL  - 98
IS  - 7
ER  - 
TY  - JOUR
A1  - Ewald, Heike
A1  - Glotzbach-Schoon, Evelyn
A1  - Gerdes, Antje B. M.
A1  - Andreatta, Marta
A1  - Müller, Mathias
A1  - Mühlberger, Andreas
A1  - Pauli, Paul
T1  - Delay and trace fear conditioning in a complex virtual learning environment - neural substrates of extinction
JF  - Frontiers in Human Neuroscience
N2  - Extinction is an important mechanism to inhibit initially acquired fear responses. There is growing evidence that the ventromedial prefrontal cortex (vmPFC) inhibits the amygdala and therefore plays an important role in the extinction of delay fear conditioning. To our knowledge, there is no evidence on the role of the prefrontal cortex in the extinction of trace conditioning up to now. Thus, we compared brain structures involved in the extinction of human delay and trace fear conditioning in a between-subjects-design in an fMRI study. Participants were passively guided through a virtual environment during learning and extinction of conditioned fear. Two different lights served as conditioned stimuli (CS); as unconditioned stimulus (US) a mildly painful electric stimulus was delivered. In the delay conditioning group (DCG) the US was administered with offset of one light (CS+), whereas in the trace conditioning group (TCG) the US was presented 4s after CS+ offset. Both groups showed insular and striatal activation during early extinction, but differed in their prefrontal activation. The vmPFC was mainly activated in the DCG, whereas the TCG showed activation of the dorsolateral prefrontal cortex (dlPFC) during extinction. These results point to different extinction processes in delay and trace conditioning. VmPFC activation during extinction of delay conditioning might reflect the inhibition of the fear response. In contrast, dlPFC activation during extinction of trace conditioning may reflect modulation of working memory processes which are involved in bridging the trace interval and hold information in short term memory.
KW  - prefrontal cortex
KW  - delay conditioning
KW  - trace conditioning
KW  - extinction
KW  - virtual reality
KW  - fMRI
KW  - medial prefrontal cortex
KW  - event-related FMRI
KW  - orbifrontal cortex
KW  - contextual fear
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116230
SN  - 1662-5161
VL  - 8
IS  - 323
ER  - 
TY  - JOUR
A1  - Karimi, Sohail M.
A1  - Freund, Matthias
A1  - Wager, Brittney M.
A1  - Knoblauch, Michael
A1  - Fromm, Jörg
A1  - M. Mueller, Heike
A1  - Ache, Peter
A1  - Krischke, Markus
A1  - Mueller, Martin J.
A1  - Müller, Tobias
A1  - Dittrich, Marcus
A1  - Geilfus, Christoph-Martin
A1  - Alfaran, Ahmed H.
A1  - Hedrich, Rainer
A1  - Deeken, Rosalia
T1  - Under salt stress guard cells rewire ion transport and abscisic acid signaling
JF  - New Phytologist
N2  - Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads.
We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function.
Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations.
Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.
KW  - soil
KW  - stomata
KW  - abscisic acid (ABA)
KW  - glycophyte Arabidopsis
KW  - guard cell
KW  - halophyte Thellungiella/Eutrema
KW  - ion transport
KW  - salt stress
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259635
VL  - 231
IS  - 3
ER  - 
TY  - JOUR
A1  - Grassinger, Julia Maria
A1  - Floren, Andreas
A1  - Müller, Tobias
A1  - Cerezo-Echevarria, Argiñe
A1  - Beitzinger, Christoph
A1  - Conrad, David
A1  - Törner, Katrin
A1  - Staudacher, Marlies
A1  - Aupperle-Lellbach, Heike
T1  - Digital lesions in dogs: a statistical breed analysis of 2912 cases
JF  - Veterinary Sciences
N2  - Breed predispositions to canine digital neoplasms are well known. However, there is currently no statistical analysis identifying the least affected breeds. To this end, 2912 canine amputated digits submitted from 2014–2019 to the Laboklin GmbH & Co. KG for routine diagnostics were statistically analyzed. The study population consisted of 155 different breeds (most common: 634 Mongrels, 411 Schnauzers, 197 Labrador Retrievers, 93 Golden Retrievers). Non-neoplastic processes were present in 1246 (43%), tumor-like lesions in 138 (5%), and neoplasms in 1528 cases (52%). Benign tumors (n = 335) were characterized by 217 subungual keratoacanthomas, 36 histiocytomas, 35 plasmacytomas, 16 papillomas, 12 melanocytomas, 9 sebaceous gland tumors, 6 lipomas, and 4 bone tumors. Malignant neoplasms (n = 1193) included 758 squamous cell carcinomas (SCC), 196 malignant melanomas (MM), 76 soft tissue sarcomas, 52 mast cell tumors, 37 non-specified sarcomas, 29 anaplastic neoplasms, 24 carcinomas, 20 bone tumors, and 1 histiocytic sarcoma. Predisposed breeds for SCC included the Schnauzer (log OR = 2.61), Briard (log OR = 1.78), Rottweiler (log OR = 1.54), Poodle (log OR = 1.40), and Dachshund (log OR = 1.30). Jack Russell Terriers (log OR = −2.95) were significantly less affected by SCC than Mongrels. Acral MM were significantly more frequent in Rottweilers (log OR = 1.88) and Labrador Retrievers (log OR = 1.09). In contrast, Dachshunds (log OR = −2.17), Jack Russell Terriers (log OR = −1.88), and Rhodesian Ridgebacks (log OR = −1.88) were rarely affected. This contrasted with the well-known predisposition of Dachshunds and Rhodesian Ridgebacks to oral and cutaneous melanocytic neoplasms. Further studies are needed to explain the underlying reasons for breed predisposition or “resistance” to the development of specific acral tumors and/or other sites.
KW  - canine
KW  - subungual
KW  - toe
KW  - tumor
KW  - inflammation
KW  - breed predisposition
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242690
SN  - 2306-7381
VL  - 8
IS  - 7
ER  - 
TY  - JOUR
A1  - Schwedhelm, Ivo
A1  - Zdzieblo, Daniela
A1  - Appelt-Menzel, Antje
A1  - Berger, Constantin
A1  - Schmitz, Tobias
A1  - Schuldt, Bernhard
A1  - Franke, Andre
A1  - Müller, Franz-Josef
A1  - Pless, Ole
A1  - Schwarz, Thomas
A1  - Wiedemann, Philipp
A1  - Walles, Heike
A1  - Hansmann, Jan
T1  - Automated real-time monitoring of human pluripotent stem cell aggregation in stirred tank reactors
JF  - Scientific Reports
N2  - The culture of human induced pluripotent stem cells (hiPSCs) at large scale becomes feasible with the aid of scalable suspension setups in continuously stirred tank reactors (CSTRs). Innovative monitoring options and emerging automated process control strategies allow for the necessary highly defined culture conditions. Next to standard process characteristics such as oxygen consumption, pH, and metabolite turnover, a reproducible and steady formation of hiPSC aggregates is vital for process scalability. In this regard, we developed a hiPSC-specific suspension culture unit consisting of a fully monitored CSTR system integrated into a custom-designed and fully automated incubator. As a step towards cost-effective hiPSC suspension culture and to pave the way for flexibility at a large scale, we constructed and utilized tailored miniature CSTRs that are largely made from three-dimensional (3D) printed polylactic acid (PLA) filament, which is a low-cost material used in fused deposition modelling. Further, the monitoring tool for hiPSC suspension cultures utilizes in situ microscopic imaging to visualize hiPSC aggregation in real-time to a statistically significant degree while omitting the need for time-intensive sampling. Suitability of our culture unit, especially concerning the developed hiPSC-specific CSTR system, was proven by demonstrating pluripotency of CSTR-cultured hiPSCs at RNA (including PluriTest) and protein level.
KW  - Biomedical engineering
KW  - Stem-cell biotechnology
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202649
VL  - 9
ER  - 
TY  - JOUR
A1  - Thorn, Simon
A1  - Chao, Anne
A1  - Georgiev, Konstadin B.
A1  - Müller, Jörg
A1  - Bässler, Claus
A1  - Campbell, John L.
A1  - Jorge, Castro
A1  - Chen, Yan-Han
A1  - Choi, Chang-Yong
A1  - Cobb, Tyler P.
A1  - Donato, Daniel C.
A1  - Durska, Ewa
A1  - Macdonald, Ellen
A1  - Feldhaar, Heike
A1  - Fontaine, Jospeh B.
A1  - Fornwalt, Paula J.
A1  - Hernández Hernández, Raquel María
A1  - Hutto, Richard L.
A1  - Koivula, Matti
A1  - Lee, Eun-Jae
A1  - Lindenmayer, David
A1  - Mikusinski, Grzegorz
A1  - Obrist, Martin K.
A1  - Perlík, Michal
A1  - Rost, Josep
A1  - Waldron, Kaysandra
A1  - Wermelinger, Beat
A1  - Weiß, Ingmar
A1  - Zmihorski, Michal
A1  - Leverkus, Alexandro B.
T1  - Estimating retention benchmarks for salvage logging to protect biodiversity
JF  - Nature Communications
N2  - Forests are increasingly affected by natural disturbances. Subsequent salvage logging, a widespread management practice conducted predominantly to recover economic capital, produces further disturbance and impacts biodiversity worldwide. Hence, naturally disturbed forests are among the most threatened habitats in the world, with consequences for their associated biodiversity. However, there are no evidence-based benchmarks for the proportion of area of naturally disturbed forests to be excluded from salvage logging to conserve biodiversity. We apply a mixed rarefaction/extrapolation approach to a global multi-taxa dataset from disturbed forests, including birds, plants, insects and fungi, to close this gap. We find that 757% (mean +/- SD) of a naturally disturbed area of a forest needs to be left unlogged to maintain 90% richness of its unique species, whereas retaining 50% of a naturally disturbed forest unlogged maintains 73 +/- 12% of its unique species richness. These values do not change with the time elapsed since disturbance but vary considerably among taxonomic groups. Salvage logging has become a common practice to gain economic returns from naturally disturbed forests, but it could have considerable negative effects on biodiversity. Here the authors use a recently developed statistical method to estimate that ca. 75% of the naturally disturbed forest should be left unlogged to maintain 90% of the species unique to the area.
KW  - natural disturbance
KW  - bird communities
KW  - forest
KW  - management
KW  - beetle
KW  - conservation
KW  - windthrow
KW  - diversity
KW  - impact
KW  - fire
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230512
VL  - 11
ER  -