Abstract 3852: Identification and functional characterization of T-cell lymphoma invasion and metastasis 2 (TIAM2) in neuronal cells

Abstract

Abstract T-Cell Lymphoma Invasion and Metastasis 2 (TIAM2) gene was identified as the homolog for human TIAM1 gene, a Rac-specific guanine nucleotide exchange factor (GEF), and classified as a member of TIAM GEF subfamily. Although functions of TIAM family proteins have been extensively studied, the characteristics of human TIAM2 remain largely unknown. In this study we systematically investigate the cellular function of TIAM2. Two mRNA isoforms of TIAM2, TIAM2S and TIAM2L, were detected and showed distinct expression patterns in various human tissues. Although both mRNAs are highly expressed in many human tissues, no TIAM2L protein can be detected in any of the examined human tissues and cell lines. In addition, TIAM2S protein only expressed in neuron of restricted regions in the human brain. Overexpression of TIAM2S-GFP fusion protein revealed a cytosolic distribution in both HeLa and NIH3T3 cells. Using LC/MS/MS and enzymatic analysis, TIAM2S was shown to be an O-linked glycoprotein. As transiently transfected TIAM2S-fusion protein neither translocate onto the cell membrane, nor exhibit GEF activity to RhoGTPases in vivo, these data suggested human TIAM2S is not a classical GEF and its functional role in normal brain may differ from other TIAM members. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3852. doi:10.1158/1538-7445.AM2011-3852