When:
Tuesday, May 10, 2016
12:00 PM - 1:00 PM CT
Where: Robert H Lurie Medical Research Center, Baldwin Auditorium, 303 E. Superior, Chicago, IL 60611 map it
Audience: Faculty/Staff - Student - Post Docs/Docs - Graduate Students
Contact:
Dr. Mojgan Naghavi
(312) 503-4294
Group: Department of Microbiology-Immunology Seminars/Events
Category: Lectures & Meetings
Microbiology-Immunology Seminar Series
"Embryonic stem (ES) and carcinoma (EC) cells actively silence newly established proviral DNAs. The Goff lab is characterizing two distinct mechanisms of silencing in embryonic cells infected by the Moloney murine leukemia virus (MLV): a highly efficient one targeted to the proline tRNA primer binding site (PBSpro) on the MLV genome, and a less efficient one occurring independently of the PBS. The PBS-specific silencing is mediated by TRIM28 (Kap1), a known transcriptional silencer, tethered to the DNA by ZFP809, an ES cell-specific zinc finger protein. ZFP809 is regulated at the level of protein turnover: the ZFP809 protein is stable in ES cells but degraded rapidly in differentiated cells in a ubiquitin-dependent proteosomal pathway. The Goff lab is also characterizing a PBS-independent system acting more broadly on incoming viral DNAs in ES cells. A major player in this process is Yin Yang1 (YY1), a GLI-Kruppel zinc finger protein, ubiquitously expressed and highly conserved between species.
The lab has found that human EC cells also fail to express MLV genomes, and that the integrated viral DNA is silenced by chromatin and DNA methylation. It is likely that much of the machinery involved in this process is similar to that used in silencing HIV-1 DNA in latently infected cells."
Stephen Goff, PhD
Columbia University Medical Center
Host: Dr. Mojgan Naghavi