Calrexin and calreticulin are -

Ans. is 'b' i.e., Chaperons Calrexin and calreticulino Calreticulin & calrexin are major Ca2+ binding (storage) chaperones in the endoplasmic reticulumo These Ca2+ binding chaperones, which are involved in protein folding, posttranslational modification, Ca2+ storage and release, and lipid synthesis and metabolism.o They are the key component of the calreticulin/calnexin cycle which is responsible for the folding of newly synthesized proteins and glycoproteins and for quality control pathways in the endoplasmic reticulumo They bind to misfolded proteins and prevent them from being exported from the endoplasmic reticulum to the Golgi apparatus.o Calreticulin and calnexin are also integral proteins in the production of MHC class I Proteins