B-Cell Translocation Gene 4 (BTG4)

BTG4, a novel member of the PC3/BTG/TOB family of growth inhibitory genes. encodes a deduced 223-amino acid protein with a calculated molecular mass of 25 kD. The protein contains potential phosphorylation sites for protein kinase C and casein kinase II. It shares approximately 73% amino acid sequence identity with mouse Pc3b. Buanne et al. (2000) demonstrated that BTG4 has antiproliferative properties and can induce G1 arrest. Northern blot analysis of both human and mouse tissues detected a 1.4-kb transcript in testis only. RT-PCR in mouse showed high expression in oocyte and in preimplantation embryos. Analysis of Pc3b expression during mouse development indicated a specific localization in the olfactory epithelium at midgestation, suggesting that BTG4 may be involved in the differentiation of the neuronal structure.