Transmembrane protein 151B

The Transmembrane protein 151B gene is also known as TMEM151B, C6orf137, and bA444E17.5.^[6]

The gene is located on the positive strand of chromosome 6 at the location 6p21.1 from the chromosome position 44270450 to 44279444, for a total length of 8,995 base pairs.^[7] It is a complex locus that contains both TMEM151B and SPATS1.^[8] TMEM151B has one paralog: TMEM151A.^[9]

The mRNA contains 3 exons, with a transcribed mRNA length of 4911bp, and the coding region containing 1701bp.^[7]

The protein has a length of 566 amino acids and contains two transmembrane domains.^[6] According to Compute pI/Mw,  molecular weight of approximately 61 kDa, which matches the weight listed on NCBI, and a theoretical isoelectric point of 6.72.^[11][6] The human TMEM151B protein composition is poor in lysine and arginine, lysine comprising 1.4% of the amino acids and arginine making up 0.8% of the total protein. The mouse ortholog is also arginine poor.^[12]

Expression

RNA-seq gene expression profiling shows high expression in the brain, and notable expression in the testes.^[14] NCBI geo profiles similarly show localization to the brain tissues.^[15] Within the mouse brain, TMEM151B has high expression particularly within the cerebellum, medulla, and olfactory bulb according to the Allen Brain Atlas.^[13]

The TMEM151B gene is conserved within most vertebrates, and appears to be conserved within some invertebrates. Its paralog, TMEM151A, has a 47.7% sequence identity with TMEM151B.^[9][18] The evolution rate is relatively slow: between the rate of change in fibrinogen alpha and cytochrome c.^[9][19]

Alternative splicing of TMEM151B along with 4 other genes were linked to colorectal cancer.^[20] It was also found to be up-regulated in post-menopausal breast cancer.^[21][22] A SNP found within TMEM151B is associated with the development of lean muscle.^[23]