Protein encoded by the GRAMD2A gene
GRAM domain-containing 2A protein (GRAMD2A; formerly GRAMD2) is a protein encoded by the GRAMD2A gene .[ 5] Like GRAMD2B , the protein consists of a GRAM domain and a transmembrane domain that anchors it to the endoplasmic reticulum .[ 6] [ 7]
GRAMD2A is a mammalian representative of the yeast lipid transfer proteins anchored at a membrane contact site (LAM) family.[ 7] It has four paralogs : GRAMD1A , GRAMD1B , GRAMD1C and GRAMD2B. Unlike LAM and its paralogs except GRAMD2B, GRAMD2A lacks a VASt domain .
The protein localizes to sites where membranes from different organelles are in close apposition.[ 7] There, it tethers the endoplasmic reticulum to the plasma membrane through its GRAM domain binding phosphatidylinositol 4,5-bisphosphate in the plasma membrane at sites enriched for the phospholipid .[ 7] The protein ensures proper stromal interaction molecule 1 (STIM1) recruitment to these sites of membrane contact as part of the store-operated calcium entry pathway – a component of intracellular calcium homeostasis .[ 7]
References
^ a b c GRCh38: Ensembl release 89: ENSG00000175318 – Ensembl , May 2017
^ a b c GRCm38: Ensembl release 89: ENSMUSG00000074259 – Ensembl , May 2017
^ "Human PubMed Reference:" . National Center for Biotechnology Information, U.S. National Library of Medicine .
^ "Mouse PubMed Reference:" . National Center for Biotechnology Information, U.S. National Library of Medicine .
^ "GRAMD2A GRAM domain containing 2A [ Homo sapiens (human) ]" . Retrieved March 7, 2020 .
^ "RecName: Full=GRAM domain-containing protein 2A)" . Retrieved March 7, 2020 .
^ a b c d e Besprozvannaya M, Dickson E, Li H, Ginburg KS, Bers DM, Auwerx J, Nunnari J (February 2018). "GRAM domain proteins specialize functionally distinct ER-PM contact sites in human cells" . eLife . 22 (7): e31019. doi :10.7554/eLife.31019 . PMC 5823543 . PMID 29469807 .