Table 3.

ER stress proteins and their essential functions (common names underlined).

ER stress protein	Full name	Other Alias	Function
BiP	Binding Immunoglobulin protein	GRP78	Folding of glycoprotein, separates from ATF-6, IRE-1 and PERK and binds to unfolded/misfolded proteins when ER stress is present.
ATF-6	Activating Transcription Factor 6	–	Binds to ER stress response elements and activates the transcription of ER chaperones such as BiP. Activation of CHOP promoter.
PERK	PRKR-like Endoplasmic Reticulum Kinase	WRS, HRI	Phosphorylates eIF2a to attenuate translation, and to upregulate expression of ATF4, leading to enhanced transcription of target genes such as CHOP.
IRE-1	Inositol Requirement Enzyme 1	DIRE-1	IRE1-alpha and IRE1-beta undergo dimerization and transphosphorylation under ER stress and converts XBP-1 pre-mRNA into XBP-1 mature mRNA
OASIS	Old Astrocyte Specifically Induced Substance	CREB3L1	Activates the transcription of target genes that are mediated by ER stress-responsive and cyclic AMP-responsive elements.
CHOP	C ⁄ EBP homologous protein	GADD153	Apoptosis, growth arrest, oxidative stress, DNA damage.
GRP58	Glucose Regulated Protein	PDIA3	Folding of nascent proteins.
CALR	Calreticulin	–	Folding of glycoproteins. Not directly involved in ER stress.
CANX	Calnexin	MHC class 1 antigen binding protein p88	Folding of glycoproteins.
XBP-1	X box binding protein 1	TREB5	Transcription of ERAD components and ER chaperones. Activation of CHOP promoter