Transmembrane Protein 176B, or TMEM176B is a transmembrane protein that in humans is encoded by the TMEM176B gene. It is thought to play a role in the process of maturation of dendritic cells.

Gene

Location

TMEM176B is also known as LR8, and MS4B2. The gene is found on the minus end of

Chromosome 7 Chromosome 7 is one of the 23 pairs of chromosomes in humans, who normally have two copies of this chromosome. Chromosome 7 spans about 160 million base pairs (the building material of DNA) and represents between 5 and 5.5 percent of the total DN ...

, on the long arm at position 7q36.1. The starting position of the gene is at 150,791,287 and goes to 150,801,360. It has 10,074 base pairs and has a total of 11 exons.

Gene

TMEM176A and LOC105375566 is a neighbor of TMEM176B.

Expression

The gene is found to be most expressed in the

liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

with the

kidney In humans, the kidneys are two reddish-brown bean-shaped blood-filtering organ (anatomy), organs that are a multilobar, multipapillary form of mammalian kidneys, usually without signs of external lobulation. They are located on the left and rig ...

being the second most expressed tissue. TMEM176B Tissue Expression

]

Transcript variants

There are 3 isoforms (A, B, C) of this gene with variants of isoform A and C. Isoform A variant 1 has 1444 nucleotides that encode 270 amino acids. There are 17 alternatively spliced variants with 1 unspliced transcript variant.

Homology

Paralogs

There is one Sequence homology, paralog of TMEM176B which is TMEM176A.

Orthologs

Below is a table of

orthologs Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of life. Two segments of DNA can have shared ancestry because of three phenomena: either a spec ...

of TMEM176B, these include close and somewhat distant orthologs. There are around 125 orthologs of the gene ranging from primates to mice and to certain species of fish.

Homologs

The homologs of this gene include chimpanzee,

rhesus monkey The rhesus macaque (''Macaca mulatta''), colloquially rhesus monkey, is a species of Old World monkey. There are between six and nine recognised subspecies split between two groups, the Chinese-derived and the Indian-derived. Generally brown or g ...

, dog, cow, mouse, and rat.

Protein

The molecular weight of TMEM176B is 29.1 kilodaltons (kDa). The protein is rich in

valine Valine (symbol Val or V) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated −NH3+ form under biological conditions), an α- carboxylic acid group (which is in the deproton ...

and poor in

aspartic acid Aspartic acid (symbol Asp or D; the ionic form is known as aspartate), is an α-amino acid that is used in the biosynthesis of proteins. The L-isomer of aspartic acid is one of the 22 proteinogenic amino acids, i.e., the building blocks of protei ...

. There are 4 transmembrane regions within TMEM176B isoform a. There is a CD20 domain from 198-687.

Domains

The CD20-like family includes the CD20 gene but is part of the family pfam04103 which is part of superfamily cl04401. This specific domain region is 489 bp.

Secondary structure

TMEM176B is composed of alpha helices, beta strands and TM helices. The Alpha helices make up most of the secondary structure followed by TM helices.

Subcellular localization

Mainly localized to the Golgi apparatus but is additionally localized to the plasma membrane and nucleoplasm.

Protein-protein interactions

The protein interacts most commonly with TMEM176A. It also interacts with TMEM47 and CPXM1 (carboxypeptidase 1) but at lower levels. Diagram of the TMEM176B interacting proteins.

Regulation

Gene

There are 11 promoters in TMEM176B. The promoter region before isoform a is 1101 bp and covers 150,799,077-150,800,177.

Protein

There are 4 phosphorylation sites in TMEM176B isoform a.Transmembrane Protein 176B Isoform A omo Sapiens- Protein - NCBI". Ncbi.Nlm.Nih.Gov, 2019, https://www.ncbi.nlm.nih.gov/protein/NP_054739.3.

Clinical significance

There has been research that indicates that TMEM176B is associated with cancer when an abnormal of the gene accumulates.

References

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