The VASt (VAD1 Analog of StAR-related lipid transfer) domain is conserved across eukaryotes and is structurally related to Bet v1-like domains, including START lipid-binding domains. The 190-amino acid VASt domain is predominantly associated with lipid binding domains such as GRAM Pfam:PF02893, C2 and PH domains. The VASt domain is likely to have a function in binding large hydrophobic ligands and may be specific for sterol [1, 2]. The predicted structure of the VASt domain is a two-layer sandwich alpha beta fold, also called 'helix grip fold', containing three alpha helices (alpha1 to 3), six beta-sheets (beta1 to 6) and two loops (omega1 and 2) numbered from N to C terminus [1]. Some proteins known to contain a VASt domain are : Plant vascular associated death1 (VAD1), a regulator of programmed cell death (PCD) harboring a GRAM putative lipid-binding domain. Yeast SNF1 Interacting Protein 3 (SIP3), may be involved in sterol transfer between intracellular membranes. Yeast Suicide Protein 1 (YSP1), a mitochondrial protein specifically required for the mitochondrial thread-grain transition, de-energization, and the cell death. May be involved in sterol transfer between intracellular membranes. Yeast Suicide Protein 2 (YSP2), a mitochondrial membrane protein involved in mitochondrial fragmentation and may be involved in sterol transfer between intracellular membranes.It is also found in human GramD1a-c.

1: Identification and phylogenetic analyses of VASt, an uncharacterized protein domain associated with lipid-binding domains in Eukaryotes. Khafif M, Cottret L, Balague C, Raffaele S; BMC Bioinformatics. 2014;15:222. PMID:24965341

2: A new family of StART domain proteins at membrane contact sites has a role in ER-PM sterol transport. Gatta AT, Wong LH, Sere YY, Calderon-Norena DM, Cockcroft S, Menon AK, Levine TP; Elife. 2015; [Epub ahead of print] PMID:26001273