12190
2013
eng
256
14
article
1
2015-11-12
--
--
Changes in the transcriptome of the malaria parasite Plasmodium falciparum during the initial phase of transmission from the human to the mosquito
Background: The transmission of the malaria parasite Plasmodium falciparum from the human to the mosquito is mediated by dormant sexual precursor cells, the gametocytes, which become activated in the mosquito midgut. Because gametocytes are the only parasite stages able to establish an infection in the mosquito, they play a crucial role in spreading the tropical disease. The human-to-mosquito transmission triggers important molecular changes in the gametocytes, which initiate gametogenesis and prepare the parasite for life-cycle progression in the insect vector.
Results: To better understand gene regulations during the initial phase of malaria parasite transmission, we focused on the transcriptome changes that occur within the first half hour of parasite development in the mosquito. Comparison of mRNA levels of P. falciparum gametocytes before and 30 min following activation using suppression subtractive hybridization (SSH) identified 126 genes, which changed in expression during gametogenesis. Among these, 17.5% had putative functions in signaling, 14.3% were assigned to cell cycle and gene expression, 8.7% were linked to the cytoskeleton or inner membrane complex, 7.9% were involved in proteostasis and 6.4% in metabolism, 12.7% were cell surface-associated proteins, 11.9% were assigned to other functions, and 20.6% represented genes of unknown function. For 40% of the identified genes there has as yet not been any protein evidence. For a subset of 27 genes, transcript changes during gametogenesis were studied in detail by real-time RT-PCR. Of these, 22 genes were expressed in gametocytes, and for 15 genes transcript expression in gametocytes was increased compared to asexual blood stage parasites. Transcript levels of seven genes were particularly high in activated gametocytes, pointing at functions downstream of gametocyte transmission to the mosquito. For selected genes, a regulated expression during gametogenesis was confirmed on the protein level, using quantitative confocal microscopy.
Conclusions: The obtained transcriptome data demonstrate the regulations of gene expression immediately following malaria parasite transmission to the mosquito. Our findings support the identification of proteins important for sexual reproduction and further development of the mosquito midgut stages and provide insights into the genetic basis of the rapid adaption of Plasmodium to the insect vector.
BMC Genomics
10.1186/1471-2164-14-256
1471-2164
urn:nbn:de:bvb:20-opus-121905
BMC Genomics 2013, 14:256. doi:10.1186/1471-2164-14-256
Che Julius Ngwa
Matthias Scheuermayer
Gunnar Rudolf Mair
Selina Kern
Thomas Brügl
Christine Clara Wirth
Makoah Nigel Aminake
Jochen Wiesner
Rainer Fischer
Andreas Vilcinskas
Gabriele Pradel
eng
uncontrolled
parasitophorous vacuole
eng
uncontrolled
sexual development
eng
uncontrolled
gametocyte
eng
uncontrolled
transcriptome
eng
uncontrolled
signal peptide peptidase
eng
uncontrolled
host cell interface
eng
uncontrolled
alpha-tubulin-II
eng
uncontrolled
life-cycle
eng
uncontrolled
protein kinases
eng
uncontrolled
in-vitro
eng
uncontrolled
erythroyte invation
eng
uncontrolled
blocking antibodies
eng
uncontrolled
malaria
eng
uncontrolled
plasmodium falciparum
eng
uncontrolled
gametogenesis
eng
uncontrolled
mosquito
eng
uncontrolled
transmission
Medizin und Gesundheit
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/12190/008_Ngwa_BMC_Genomics.pdf
18668
2016
eng
155-166
93
article
1
2019-09-02
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--
Contact of myeloma cells induces a characteristic transcriptome signature in skeletal precursor cells-implications for myeloma bone disease
Physical interaction of skeletal precursors with multiple myeloma cells has been shown to suppress their osteogenic potential while favoring their tumor-promoting features. Although several transcriptome analyses of myeloma patient-derived mesenchymal stem cells have displayed differences compared to their healthy counterparts, these analyses insufficiently reflect the signatures mediated by tumor cell contact, vary due to different methodologies, and lack results in lineage-committed precursors. To determine tumor cell contact-mediated changes on skeletal precursors, we performed transcriptome analyses of mesenchymal stem cells and osteogenic precursor cells cultured in contact with the myeloma cell line INA-6. Comparative analyses confirmed dysregulation of genes which code for known disease-relevant factors and additionally revealed upregulation of genes that are associated with plasma cell homing, adhesion, osteoclastogenesis, and angiogenesis. Osteoclast-derived coupling factors, a dysregulated adipogenic potential, and an imbalance in favor of anti-anabolic factors may play a role in the hampered osteoblast differentiation potential of mesenchymal stem cells. Angiopoietin-Like 4 (ANGPTL4) was selected from a list of differentially expressed genes as a myeloma cell contact-dependent target in skeletal precursor cells which warranted further functional analyses. Adhesion assays with full-length ANGPTL4-coated plates revealed a potential role of this protein in INA6 cell attachment. This study expands knowledge of the myeloma cell contact-induced signature in the stromal compartment of myelomatous bones and thus offers potential targets that may allow detection and treatment of myeloma bone disease at an early stage.
Bone
10.1016/j.bone.2016.08.006
urn:nbn:de:bvb:20-opus-186688
Bone (2016) 93, 155-166. https://doi.org/10.1016/j.bone.2016.08.006
false
true
CC BY: Creative-Commons-Lizenz: Namensnennung 4.0 International
Julia Dotterweich
Katrin Schlegelmilch
Alexander Keller
Beate Geyer
Doris Schneider
Sabine Zeck
Robert J. J. Tower
Regina Ebert
Franz Jakob
Norbert Schütze
eng
uncontrolled
marrow stromal cells
eng
uncontrolled
Endothelial growth-factor
eng
uncontrolled
precedes multiple-myeloma
eng
uncontrolled
monoclonial gammopathy
eng
uncontrolled
in-vitro
eng
uncontrolled
mesenchymal stem-cells
eng
uncontrolled
undetermined significance
eng
uncontrolled
angiogenic cytokines
eng
uncontrolled
peripheral-blood
eng
uncontrolled
gene-expression
eng
uncontrolled
Multiple myeloma
eng
uncontrolled
Bone disease
eng
uncontrolled
Angiopoietin-like 4
eng
uncontrolled
Gene expression profiling
eng
uncontrolled
Mesenchymal stem cells
eng
uncontrolled
Osteogenic precursor cells
Biowissenschaften; Biologie
Medizin und Gesundheit
open_access
Lehrstuhl für Orthopädie
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/18668/Dotterweich_Bone_2016.pdf
11540
2014
eng
e105732
9
9
article
1
2015-07-07
--
--
Inhibition of the SR Protein-Phosphorylating CLK Kinases of Plasmodium falciparum Impairs Blood Stage Replication and Malaria Transmission
Cyclin-dependent kinase-like kinases (CLKs) are dual specificity protein kinases that phosphorylate Serine/Arginine-rich (SR) proteins involved in pre-mRNA processing. Four CLKs, termed PfCLK-1-4, can be identified in the human malaria parasite Plasmodium falciparum, which show homology with the yeast SR protein kinase Sky1p. The four PfCLKs are present in the nucleus and cytoplasm of the asexual blood stages and of gametocytes, sexual precursor cells crucial for malaria parasite transmission from humans to mosquitoes. We identified three plasmodial SR proteins, PfSRSF12, PfSFRS4 and PfSF-1, which are predominantly present in the nucleus of blood stage trophozoites, PfSRSF12 and PfSF-1 are further detectable in the nucleus of gametocytes. We found that recombinantly expressed SR proteins comprising the Arginine/Serine (RS)-rich domains were phosphorylated by the four PfCLKs in in vitro kinase assays, while a recombinant PfSF-1 peptide lacking the RS-rich domain was not phosphorylated. Since it was hitherto not possible to knock-out the pfclk genes by conventional gene disruption, we aimed at chemical knock-outs for phenotype analysis. We identified five human CLK inhibitors, belonging to the oxo-beta-carbolines and aminopyrimidines, as well as the antiseptic chlorhexidine as PfCLK-targeting compounds. The six inhibitors block P. falciparum blood stage replication in the low micromolar to nanomolar range by preventing the trophozoite-to-schizont transformation. In addition, the inhibitors impair gametocyte maturation and gametogenesis in in vitro assays. The combined data show that the four PfCLKs are involved in phosphorylation of SR proteins with essential functions for the blood and sexual stages of the malaria parasite, thus pointing to the kinases as promising targets for antimalarial and transmission blocking drugs.
PLOS ONE
10.1371/journal.pone.0105732
1932-6203
25188378
urn:nbn:de:bvb:20-opus-115405
PLoS ONE 9(9): e105732. doi:10.1371/journal.pone.0105732
Selina Kern
Shruti Agarwal
Kilian Huber
Andre P. Gehring
Benjamin Strödke
Christine C. Wirth
Thomas Brügl
Liane Onambele Abodo
Thomas Dandekar
Christian Doerig
Rainer Fischer
Andrew B. Tobin
Mahmood M. Alam
Franz Bracher
Gabriele Pradel
eng
uncontrolled
parasite
eng
uncontrolled
expression
eng
uncontrolled
mosquito
eng
uncontrolled
splicing factors
eng
uncontrolled
lactate dehydrogenase
eng
uncontrolled
xanthurenic acid
eng
uncontrolled
in-vitro
eng
uncontrolled
RNA-SEQ
eng
uncontrolled
identification
eng
uncontrolled
culture
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/11540/046_Kern_Plos_One.pdf
13341
2013
eng
e59400
3
8
article
1
2016-05-12
--
--
p53 Gene Targeting by Homologous Recombination in Fish ES Cells
Background: Gene targeting (GT) provides a powerful tool for the generation of precise genetic alterations in embryonic stem (ES) cells to elucidate gene function and create animal models for human diseases. This technology has, however, been limited to mouse and rat. We have previously established ES cell lines and procedures for gene transfer and selection for homologous recombination (HR) events in the fish medaka (Oryzias latipes).
Methodology and Principal Findings: Here we report HR-mediated GT in this organism. We designed a GT vector to disrupt the tumor suppressor gene p53 (also known as tp53). We show that all the three medaka ES cell lines, MES1 similar to MES3, are highly proficient for HR, as they produced detectable HR without drug selection. Furthermore, the positive-negative selection (PNS) procedure enhanced HR by similar to 12 folds. Out of 39 PNS-resistant colonies analyzed, 19 (48.7%) were positive for GT by PCR genotyping. When 11 of the PCR-positive colonies were further analyzed, 6 (54.5%) were found to be bona fide homologous recombinants by Southern blot analysis, sequencing and fluorescent in situ hybridization. This produces a high efficiency of up to 26.6% for p53 GT under PNS conditions. We show that p53 disruption and long-term propagation under drug selection conditions do not compromise the pluripotency, as p53-targeted ES cells retained stable growth, undifferentiated phenotype, pluripotency gene expression profile and differentiation potential in vitro and in vivo.
Conclusions: Our results demonstrate that medaka ES cells are proficient for HR-mediated GT, offering a first model organism of lower vertebrates towards the development of full ES cell-based GT technology.
PLoS One
10.1371/journal.pone.0059400
urn:nbn:de:bvb:20-opus-133416
PLoS ONE 8(3): e59400. doi:10.1371/journal.pone.0059400
Yan Yan
Ni Hong
Tiansheng Chen
Mingyou Li
Tiansu Wang
Guijun Guan
Yongkang Qiao
Songlin Chen
Manfred Schartl
Chang-Ming Li
Yunhan Hong
eng
uncontrolled
mouse
eng
uncontrolled
in-vitro
eng
uncontrolled
drug selection
eng
uncontrolled
chimera formation
eng
uncontrolled
medakafish oryzias latipes
eng
uncontrolled
embryonic stem-cells
eng
uncontrolled
zebrafish
eng
uncontrolled
differentiation
eng
uncontrolled
cultures
eng
uncontrolled
pluripotency
Physiologie und verwandte Themen
open_access
Theodor-Boveri-Institut für Biowissenschaften
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/13341/090_Yan_Plos_One.pdf