tailieunhanh - Báo cáo khoa học: Molecular and functional characterization of a novel splice variant of ANKHD1 that lacks the KH domain and its role in cell survival and apoptosis

Multiple ankyrin repeat motif-containing proteins play an important role in protein–protein interactions. ANKHD1 proteins are known to possess multiple ankyrin repeat domains and a single KH domain with no known function. Using yeast two-hybrid system analysis, we identified a novel splice variant of ANKHD1. This splice variant of ANKHD1, which we designated as HIV-1 Vpr-binding ankyrin repeat protein (VBARP), does not contain the signature KH domain, and codes for only a single ankyrin repeat motif. . | ềFEBS Journal Molecular and functional characterization of a novel splice variant of ANKHD1 that lacks the KH domain and its role in cell survival and apoptosis Melissa C. Miles1 Michelle L. Janket1 Elizabeth D. A. Wheeler1 Ansuman Chattopadhyay2 Biswanath Majumder1 Jeremy DeRicco1 Elizabeth A. Schafer1 and Velpandi Ayyavoo1 1 Department of Infectious Diseases Microbiology Graduate Schoolof Public Health University of Pittsburgh PA USA 2 Health Sciences Library System University of Pittsburgh PA USA Keywords ANKHD1 ankyrin repeats apoptosis cell survival HIV-1 Vpr Correspondence V. Ayyavoo Department of Infectious Diseases and Microbiology Graduate School of Public Health University of Pittsburgh 130 DeSoto Street Pittsburgh PA 15261 USA Fax 1 412 624 5612 Tel 1 412 624 3070 E-mail Velpandi@ Received 16 May 2005 revised 7 June 2005 accepted 14 June 2005 doi Multiple ankyrin repeat motif-containing proteins play an important role in protein-protein interactions. ANKHD1 proteins are known to possess multiple ankyrin repeat domains and a single KH domain with no known function. Using yeast two-hybrid system analysis we identified a novel splice variant of ANKHD1. This splice variant of ANKHD1 which we designated as HIV-1 Vpr-binding ankyrin repeat protein VBARP does not contain the signature KH domain and codes for only a single ankyrin repeat motif. We characterized VBARP by molecular and functional analysis revealing that VBARP is ubiquitously expressed in different tissues as well as cell lines of different lineage. In addition BLAST searches indicated that orthologs and homologs to VBARP exist in different phyla suggesting that VBARP might be evolutionarily conserved and thus may be involved in basic cellular function s . Furthermore biochemical analysis revealed the presence of two VBARP isoforms coding for 69 and 49 kDa polypeptides respectively that are primarily localized in the cytoplasm. Functional analysis using .