[6][7] GRAMD2A is a mammalian representative of the yeast lipid transfer proteins anchored at a membrane contact site (LAM) family.

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.