OASIS (old astrocyte specifically-induced substance) is a 57 - 60 kDa member of the CREB/ATF family of transcription factors. Human OASIS is 519 amino acids (aa) in length. It is an ER transmembrane protein with a cytosolic N-terminus (aa 1 - 374) and a luminal C-terminus. The N-terminus contains one b-Zip region (aa 292 - 353).
Misfolded proteins in the endoplasmic reticulum induce proteolytic cleavage of OASIS. The released 66 kDa N-terminus translocates to the nucleus to activate stress response genes. There is one alternate splice form that shows a deletion of aa 112 - 198. Over aa 1 - 111, human OASIS shares 96% aa sequence identity with mouse OASIS.