cAMP responsive element-binding protein 3-like protein 1 (OASIS, CREB3L1, PSEC0238)

Function

• franscription factor
• acts during endoplasmic reticulum stress by activating unfolded protein response target genes
• specifically involved in ER-stress response in astrocytes in the central nervous system
• role in gliosis
• in vitro, binds to box-B element, cAMP response element (CRE) & CRE-like sequences, & activates transcription through box-B element but not through CRE

Structure

• belongs to the bZIP family, ATF subfamily
• contains 1 bZIP domain

Compartment

• endoplasmic reticulum membrane
• processed form: nucleus
• under ER stress the cleaved N-terminal cytoplasmic domain translocates into nucleus
• controlled by regulated intramembrane proteolysis
• following ER stress a fragment containing the cytoplasmic transcription factor domain is released by proteolysis cleavage is performed sequentially by site-1 & site-2 proteases & is triggered by translocation to Golgi

Alternative splicing

named isoforms=2

Expression

• ubiquitously expressed
• high levels in pancreas & prostate
• expressed at relatively lower levels in brain

More general terms

• basic leucine zipper (bZIP) family protein
• glycoprotein
• membrane protein

Database

• UniProt: http://www.uniprot.org/uniprot/Q96BA8.html