Both of them are localized within the endoplasmic reticulum ( er ) and possess atp - binding sites . envidence has shown that grps function as molecular chaperones by assisting in the proper folding and assembly of proteins within the er 同时他们又是分布在内质网( endoplasmicreticulumer )腔内的分子伴侣,具有弱的atp酶活性,与atp结合后可以协助新生蛋白质的转位、折叠以及寡聚蛋白的组装。