GRAM domain-containing 2B protein (GRAMD2B; formerly GRAMD3), also known as NS3TP2 and HCV NS3-transactivated protein 2 is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...

encoded by the GRAMD2B

gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...

. GRAMD2B has four

paralogs 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 sp ...

: GRAMD1A, GRAMD1B, GRAMD1C and GRAMD2A. These proteins are mammalian representatives of the

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to consti ...

lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids incl ...

transfer proteins anchored at a membrane contact site (LAM) family. GRAMD2B consists of a

GRAM domain The GRAM domain is found in glucosyltransferases, myotubularins and other membrane-associated proteins. The structure of the GRAM domain is similar to that found in PH domains. Proteins containing GRAM domains are found in all eukaryotes and b ...

and a

transmembrane domain A transmembrane domain (TMD) is a membrane-spanning protein domain. TMDs generally adopt an alpha helix topological conformation, although some TMDs such as those in porins can adopt a different conformation. Because the interior of the lipid b ...

anchoring it to the

endoplasmic reticulum The endoplasmic reticulum (ER) is, in essence, the transportation system of the eukaryotic cell, and has many other important functions such as protein folding. It is a type of organelle made up of two subunits – rough endoplasmic reticulum ( ...

. Similar to GRAMD2A, GRAMD2B lacks the VASt domain found in LAM and GRAMD1 proteins. Its function has not yet been defined, but is likely similar to that of GRAMD2A.

References

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