RAB36, Member RAS Oncogene Family (RAB36)

RAB36 encodes a deduced 333-amino acid protein that contains 3 phosphate/magnesium-binding motifs, 3 guanine-binding motifs, a tyrosine kinase phosphorylation site, and a C-terminal isoprenylation signal. It shares high amino acid sequence identity with mouse Rab23 and human RAB13. Northern blot analysis revealed 4.0- and 2.2-kb mRNAs in all human tissues examined. The larger transcript contains a longer 3-prime noncoding sequence. RT-PCR analysis revealed expression of RAB36 mRNAs in 1 MRT cell line and overexpression in 2 others. Direct sequencing of cDNA from these 3 cell lines showed neither nonsense nor frameshift mutations. Moreover, a colony-formation assay indicated that RAB36 is not concerned with cell proliferation or cell death.