@article{SieglPrustyKarunakaranetal.2014, author = {Siegl, Christine and Prusty, Bhupesh K. and Karunakaran, Karthika and Wischhusen, J{\"o}rg and Rudel, Thomas}, title = {Tumor Suppressor p53 Alters Host Cell Metabolism to Limit Chlamydia trachomatis Infection}, series = {Cell Reports}, volume = {9}, journal = {Cell Reports}, number = {3}, issn = {2211-1247}, doi = {10.1016/j.celrep.2014.10.004}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-118200}, pages = {918-929}, year = {2014}, abstract = {Obligate intracellular bacteria depend entirely on nutrients from the host cell for their reproduction. Here, we show that obligate intracellular Chlamydia downregulate the central tumor suppressor p53 in human cells. This reduction of p53 levels is mediated by the PI3K-Akt signaling pathway, activation of HDM2, and subsequent proteasomal degradation of p53. The stabilization of p53 in human cells severely impaired chlamydial development and caused the loss of infectious particle formation. DNA-damage-induced p53 interfered with chlamydial development through downregulation of the pentose phosphate pathway (PPP). Increased expression of the PPP key enzyme glucose-6-phosphate dehydrogenase rescued the inhibition of chlamydial growth induced by DNA damage or stabilized p53. Thus, downregulation of p53 is a key event in the chlamydial life cycle that reprograms the host cell to create a metabolic environment supportive of chlamydial growth.}, language = {en} } @unpublished{HennigPrustyKauferetal.2021, author = {Hennig, Thomas and Prusty, Archana B. and Kaufer, Benedikt and Whisnant, Adam W. and Lodha, Manivel and Enders, Antje and Thomas, Julius and Kasimir, Francesca and Grothey, Arnhild and Herb, Stefanie and J{\"u}rges, Christopher and Meister, Gunter and Erhard, Florian and D{\"o}lken, Lars and Prusty, Bhupesh K.}, title = {Selective inhibition of microRNA processing by a herpesvirus-encoded microRNA triggers virus reactivation from latency}, edition = {submitted version}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-267858}, year = {2021}, abstract = {Herpesviruses have mastered host cell modulation and immune evasion to augment productive infection, life-long latency and reactivation thereof 1,2. A long appreciated, yet elusively defined relationship exists between the lytic-latent switch and viral non-coding RNAs 3,4. Here, we identify miRNA-mediated inhibition of miRNA processing as a novel cellular mechanism that human herpesvirus 6A (HHV-6A) exploits to disrupt mitochondrial architecture, evade intrinsic host defense and drive the latent-lytic switch. We demonstrate that virus-encoded miR-aU14 selectively inhibits the processing of multiple miR-30 family members by direct interaction with the respective pri-miRNA hairpin loops. Subsequent loss of miR-30 and activation of miR-30/p53/Drp1 axis triggers a profound disruption of mitochondrial architecture, which impairs induction of type I interferons and is necessary for both productive infection and virus reactivation. Ectopic expression of miR-aU14 was sufficient to trigger virus reactivation from latency thereby identifying it as a readily drugable master regulator of the herpesvirus latent-lytic switch. Our results show that miRNA-mediated inhibition of miRNA processing represents a generalized cellular mechanism that can be exploited to selectively target individual members of miRNA families. We anticipate that targeting miR-aU14 provides exciting therapeutic options for preventing herpesvirus reactivations in HHV-6-associated disorders like myalgic encephalitis/chronic fatigue syndrome (ME/CFS) and Long-COVID.}, language = {en} } @article{RudelKrohnePrusty2013, author = {Rudel, Thomas and Krohne, George and Prusty, Bhupesh K.}, title = {Reactivation of Chromosomally Integrated Human Herpesvirus-6 by Telomeric Circle Formation}, doi = {10.1371/journal.pgen.1004033}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111380}, year = {2013}, abstract = {More than 95\% of the human population is infected with human herpesvirus-6 (HHV-6) during early childhood and maintains latent HHV-6 genomes either in an extra-chromosomal form or as a chromosomally integrated HHV-6 (ciHHV-6). In addition, approximately 1\% of humans are born with an inheritable form of ciHHV-6 integrated into the telomeres of chromosomes. Immunosuppression and stress conditions can reactivate latent HHV-6 replication, which is associated with clinical complications and even death. We have previously shown that Chlamydia trachomatis infection reactivates ciHHV-6 and induces the formation of extra-chromosomal viral DNA in ciHHV-6 cells. Here, we propose a model and provide experimental evidence for the mechanism of ciHHV-6 reactivation. Infection with Chlamydia induced a transient shortening of telomeric ends, which subsequently led to increased telomeric circle (t-circle) formation and incomplete reconstitution of circular viral genomes containing single viral direct repeat (DR). Correspondingly, short t-circles containing parts of the HHV-6 DR were detected in cells from individuals with genetically inherited ciHHV-6. Furthermore, telomere shortening induced in the absence of Chlamydia infection also caused circularization of ciHHV-6, supporting a t-circle based mechanism for ciHHV-6 reactivation. Author Summary: Human herpesviruses (HHVs) can reside in a lifelong non-infectious state displaying limited activity in their host and protected from immune responses. One possible way by which HHV-6 achieves this state is by integrating into the telomeric ends of human chromosomes, which are highly repetitive sequences that protect the ends of chromosomes from damage. Various stress conditions can reactivate latent HHV-6 thus increasing the severity of multiple human disorders. Recently, we have identified Chlamydia infection as a natural cause of latent HHV-6 reactivation. Here, we have sought to elucidate the molecular mechanism of HHV-6 reactivation. HHV-6 efficiently utilizes the well-organized telomere maintenance machinery of the host cell to exit from its inactive state and initiate replication to form new viral DNA. We provide experimental evidence that the shortening of telomeres, as a consequence of interference with telomere maintenance, triggers the release of the integrated virus from the chromosome. Our data provide a mechanistic basis to understand HHV-6 reactivation scenarios, which in light of the high prevalence of HHV-6 infection and the possibility of chromosomal integration of other common viruses like HHV-7 have important medical consequences for several million people worldwide.}, language = {en} } @article{HerwegHansmeierOttoetal.2015, author = {Herweg, Jo-Ana and Hansmeier, Nicole and Otto, Andreas and Geffken, Anna C. and Subbarayal, Prema and Prusty, Bhupesh K. and Becher, D{\"o}rte and Hensel, Michael and Schaible, Ulrich E. and Rudel, Thomas and Hilbi, Hubert}, title = {Purification and proteomics of pathogen-modified vacuoles and membranes}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {5}, journal = {Frontiers in Cellular and Infection Microbiology}, number = {48}, doi = {10.3389/fcimb.2015.00048}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151823}, year = {2015}, abstract = {Certain pathogenic bacteria adopt an intracellular lifestyle and proliferate in eukaryotic host cells. The intracellular niche protects the bacteria from cellular and humoral components of the mammalian immune system, and at the same time, allows the bacteria to gain access to otherwise restricted nutrient sources. Yet, intracellular protection and access to nutrients comes with a price, i.e., the bacteria need to overcome cell-autonomous defense mechanisms, such as the bactericidal endocytic pathway. While a few bacteria rupture the early phagosome and escape into the host cytoplasm, most intracellular pathogens form a distinct, degradation-resistant and replication-permissive membranous compartment. Intracellular bacteria that form unique pathogen vacuoles include Legionella, Mycobacterium, Chlamydia, Simkania, and Salmonella species. In order to understand the formation of these pathogen niches on a global scale and in a comprehensive and quantitative manner, an inventory of compartment-associated host factors is required. To this end, the intact pathogen compartments need to be isolated, purified and biochemically characterized. Here, we review recent progress on the isolation and purification of pathogen-modified vacuoles and membranes, as well as their proteomic characterization by mass spectrometry and different validation approaches. These studies provide the basis for further investigations on the specific mechanisms of pathogen-driven compartment formation.}, language = {en} } @article{PrustyChowdhuryGulveetal.2018, author = {Prusty, Bhupesh K. and Chowdhury, Suvagata R. and Gulve, Nitish and Rudel, Thomas}, title = {Peptidase Inhibitor 15 (PI15) Regulates Chlamydial CPAF Activity}, series = {Frontiers in Cellular and Infection Microbiology}, volume = {8}, journal = {Frontiers in Cellular and Infection Microbiology}, number = {183}, issn = {2235-2988}, doi = {10.3389/fcimb.2018.00183}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-196918}, year = {2018}, abstract = {Obligate intracellular pathogenic Chlamydia trachomatis express several serine proteases whose roles in chlamydial development and pathogenicity are not completely understood. The chlamydial protease CPAF is expressed during the replicative phase of the chlamydial developmental cycle and is secreted into the lumen of the Chlamydia-containing vacuole called inclusion. How the secreted protease is activated in the inclusion lumen is currently not fully understood. We have identified human serine peptidase inhibitor PI15 as a potential host factor involved in the regulation of CPAF activation. Silencing expression as well as over expression of PI15 affected normal development of Chlamydia. PI15 was transported into the chlamydial inclusion lumen where it co-localized with CPAF aggregates. We show that PI15 binds to the CPAF zymogen and potentially induces CPAF protease activity at low concentrations. However, at high concentrations PI15 inhibits CPAF activity possibly by blocking its protease domain. Our findings shed light on a new aspect of chlamydial host co-evolution which involves the recruitment of host cell proteins into the inclusion to control the activation of bacterial proteases like CPAF that are important for the normal development of Chlamydia.}, language = {en} } @article{PrustyBoehmeBergmannetal.2012, author = {Prusty, Bhupesh K. and B{\"o}hme, Linda and Bergmann, Birgit and Siegl, Christine and Krause, Eva and Mehlitz, Adrian and Rudel, Thomas}, title = {Imbalanced oxidative stress causes chlamydial persistence during non-productive Human Herpes Virus co-infection}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76215}, year = {2012}, abstract = {Both human herpes viruses and Chlamydia are highly prevalent in the human population and are detected together in different human disorders. Here, we demonstrate that co-infection with human herpes virus 6 (HHV6) interferes with the developmental cycle of C. trachomatis and induces persistence. Induction of chlamydial persistence by HHV6 is independent of productive virus infection, but requires the interaction and uptake of the virus by the host cell. On the other hand, viral uptake is strongly promoted under co-infection conditions. Host cell glutathione reductase activity was suppressed by HHV6 causing NADPH accumulation, decreased formation of reduced glutathione and increased oxidative stress. Prevention of oxidative stress restored infectivity of Chlamydia after HHV6-induced persistence. We show that co-infection with Herpes simplex virus 1 or human Cytomegalovirus also induces chlamydial persistence by a similar mechanism suggesting that Chlamydia -human herpes virus co-infections are evolutionary shaped interactions with a thus far unrecognized broad significance.}, subject = {Biologie}, language = {en} } @article{RudelPrustySiegletal.2014, author = {Rudel, Thomas and Prusty, Bhupesh K. and Siegl, Christine and Gulve, Nitish and Mori, Yasuko}, title = {GP96 Interacts with HHV-6 during Viral Entry and Directs It for Cellular Degradation}, doi = {10. 1371/journal.pone.0113962}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111068}, year = {2014}, abstract = {CD46 and CD134 mediate attachment of Human Herpesvirus 6A (HHV-6A) and HHV-6B to host cell, respectively. But many cell types interfere with viral infection through rapid degradation of viral DNA. Hence, not all cells expressing these receptors are permissive to HHV-6 DNA replication and production of infective virions suggesting the involvement of additional factors that influence HHV-6 propagation. Here, we used a proteomics approach to identify other host cell proteins necessary for HHV-6 binding and entry. We found host cell chaperone protein GP96 to interact with HHV-6A and HHV-6B and to interfere with virus propagation within the host cell. In human peripheral blood mononuclear cells (PBMCs), GP96 is transported to the cell surface upon infection with HHV-6 and interacts with HHV-6A and -6B through its C-terminal end. Suppression of GP96 expression decreased initial viral binding but increased viral DNA replication. Transient expression of human GP96 allowed HHV-6 entry into CHO-K1 cells even in the absence of CD46. Thus, our results suggest an important role for GP96 during HHV-6 infection, which possibly supports the cellular degradation of the virus.}, language = {en} } @article{RasaNoraKrukleHenningetal.2018, author = {Rasa, Santa and Nora-Krukle, Zaiga and Henning, Nina and Eliassen, Eva and Shikova, Evelina and Harrer, Thomas and Scheibenbogen, Carmen and Murovska, Modra and Prusty, Bhupesh K.}, title = {Chronic viral infections in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)}, series = {Journal of Translational Medicine}, volume = {16}, journal = {Journal of Translational Medicine}, number = {268}, doi = {10.1186/s12967-018-1644-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-224960}, pages = {1-25}, year = {2018}, abstract = {Background and main text: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex and controversial clinical condition without having established causative factors. Increasing numbers of cases during past decade have created awareness among patients as well as healthcare professionals. Chronic viral infection as a cause of ME/CFS has long been debated. However, lack of large studies involving well-designed patient groups and validated experimental set ups have hindered our knowledge about this disease. Moreover, recent developments regarding molecular mechanism of pathogenesis of various infectious agents cast doubts over validity of several of the past studies. Conclusions: This review aims to compile all the studies done so far to investigate various viral agents that could be associated with ME/CFS. Furthermore, we suggest strategies to better design future studies on the role of viral infections in ME/CFS.}, language = {en} } @article{GulveFrankKlepschetal.2017, author = {Gulve, Nitish and Frank, Celina and Klepsch, Maximilian and Prusty, Bhupesh K.}, title = {Chromosomal integration of HHV-6A during non-productive viral infection}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, number = {512}, doi = {10.1038/s41598-017-00658-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158117}, year = {2017}, abstract = {Human herpesvirus 6A (HHV-6A) and 6B (HHV-6B) are two different species of betaherpesviruses that integrate into sub-telomeric ends of human chromosomes, for which different prevalence rates of integration have been reported. It has been demonstrated that integrated viral genome is stable and is fully retained. However, study of chromosomally integrated viral genome in individuals carrying inherited HHV-6 (iciHHV-6) showed unexpected number of viral DR copies. Hence, we created an in vitro infection model and studied retention of full or partial viral genome over a period of time. We observed an exceptional event where cells retained viral direct repeats (DRs) alone in the absence of the full viral genome. Finally, we found evidence for non-telomeric integration of HHV-6A DR in both cultured cells and in an iciHHV-6 individual. Our results shed light on several novel features of HHV-6A chromosomal integration and provide valuable information for future screening techniques.}, language = {en} } @article{RudelPrustySiegletal.2013, author = {Rudel, Thomas and Prusty, Bhupesh K. and Siegl, Christine and Hauck, Petra and Hain, Johannes and Korhonen, Suvi J. and Hiltunen-Back, Eija and Poulakkainen, Mirja}, title = {Chlamydia trachomatis Infection Induces Replication of Latent HHV-6}, series = {PLoS ONE}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0061400}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96731}, year = {2013}, abstract = {Human herpesvirus-6 (HHV-6) exists in latent form either as a nuclear episome or integrated into human chromosomes in more than 90\% of healthy individuals without causing clinical symptoms. Immunosuppression and stress conditions can reactivate HHV-6 replication, associated with clinical complications and even death. We have previously shown that co-infection of Chlamydia trachomatis and HHV-6 promotes chlamydial persistence and increases viral uptake in an in vitro cell culture model. Here we investigated C. trachomatis-induced HHV-6 activation in cell lines and fresh blood samples from patients having Chromosomally integrated HHV-6 (CiHHV-6). We observed activation of latent HHV-6 DNA replication in CiHHV-6 cell lines and fresh blood cells without formation of viral particles. Interestingly, we detected HHV-6 DNA in blood as well as cervical swabs from C. trachomatis-infected women. Low virus titers correlated with high C. trachomatis load and vice versa, demonstrating a potentially significant interaction of these pathogens in blood cells and in the cervix of infected patients. Our data suggest a thus far underestimated interference of HHV-6 and C. trachomatis with a likely impact on the disease outcome as consequence of co-infection.}, language = {en} }