Theiler's murine encephalomyelitis protein 2C and its effect on membrane trafficking

Polioviruses;Viral proteins;Biological transport

Moës, Elien ; Ryan, Martin Denis ; Ryan, Martin Denis

University:University of St Andrews

Department:Biology (School of)

关键词: Polioviruses;    Viral proteins;    Biological transport;   

Others  :  https://research-repository.st-andrews.ac.uk/bitstream/handle/10023/540/Elien%20Moes%20PhD%20thesis.pdf?sequence=7&isAllowed=y

来源: DR-NTU

【 摘 要 】

Picornaviruses replicate in association with cytoplasmic membranes of infected cells.Poliovirus 2C and 2BC play an important role in the formation of membranous vesicles, andinduce dramatic changes in membrane trafficking. Theiler’s murine encephalomyelitis virusprotein 2C was localized in infected cells using an anti-TMEV-2C antibody. Early uponinfection, TMEV 2C was localized in the cytoplasm in an ER-like pattern. At later stages, 2Credistributed to a juxtanuclear site, which represents the viral replication site. Co-localizationwith the Golgi complex could not be observed. TMEV 2C seems to interact in vitro withreticulon 3, a highly conserved ER-associated protein. It was not possible to confirm apreviously identified interaction with AKAP10, a protein kinase anchoring protein, presumablyreflecting conformational constraints of the interaction. Two mutations in the AKAP10 bindingsite of TMEV 2C were identified, which inhibit the completion of the infectious cycle ofTMEV. The intracellular changes that occur during TMEV infection were observed. Both actinfilaments and microtubules may be used at early stages of infection; however both cytoskeletoncomponents accumulate at the periphery of the cell during late stages of infection. A computer-based analysis has demonstrated that TMEV 2C is highly similar to katanin, a microtubule-severing protein, and may play a similar role in the reorganization of microtubules duringinfection. The Golgi complex turns from a solid, crescent-shaped organelle, into a series ofpunctuate fluorescent points forming an expanding balloon-like structure surrounding theconcomitantly expanding site of virus replication. The remnants of the Golgi complex arefinally dispersed throughout the cytoplasm. Live imaging confirmed these findings. It wasobserved that PKA also undergoes displacement to the cell periphery during infection.However, BIG1 seems to locate to the viral replication site during infection, suggesting it mayplay a role during viral replication. The localization of PKA and BIG1 in the infected cell mayin part explain the observed dispersion of the Golgi complex.