pfam08327: AHSA1 (This model is not part of the current CDD release)
Activator of Hsp90 ATPase homolog 1-like protein
This family includes eukaryotic, prokaryotic and archaeal proteins that bear similarity to a C-terminal region of human activator of 90 kDa heat shock protein ATPase homolog 1 (AHSA1/p38). This protein is known to interact with the middle domain of Hsp90, and stimulate its ATPase activity. It is probably a general upregulator of Hsp90 function, particularly contributing to its efficiency in conditions of increased stress. p38 is also known to interact with the cytoplasmic domain of the VSV G protein, and may thus be involved in protein transport. It has also been reported as being underexpressed in Down's syndrome. This region is found repeated in two members of this family. The structure of YndB from Bacillus subtilis showed the helix-grip fold consisting of a beta-sheet with two small and one long alpha-helix which form a hydrophobic cavity that preferentially binds lipid-like molecules. This structure confirms its similarity with the eukaryote protein Aha1 and its classification as a member of the AHSA1 family).
Jiyao W et al.(2023). "The conserved domain database in 2023.",