ST5 Colorimetric Cell-Based ELISA

Widely expressed with the exception of peripheral blood lymphocytes. Isoform 1 is expressed in several epithelial and fibroblast (including tumorigenic) but absent in lymphoid cell lines (at protein level) . Isoform 3 is expressed in primary cell or weakly tumorigenic but not in tumorigenic cell lines (at protein level) .

Guanine nucleotide exchange factor (GEF) which may activate RAB9A and RAB9B. Promotes the exchange of GDP to GTP, converting inactive GDP-bound Rab proteins into their active GTP- bound form. May be involved in cytoskeletal organization and tumorogenicity. Isoform 1 seems to be involved in a signaling transduction pathway leading to activation of MAPK1/ERK2. Isoform 3 may block ERK2 activation stimulated by ABL1. Isoform 3 may alter cell morphology and cell growth.