part of cell cortex cortical endoplasmic reticulum cellular_component peripheral ER ER-PM peripheral junction cortical ER GO:0032541 The dynamic nature of the cortical ER and the movements it undergoes (branching and ring closure) has been shown in both yeast and mammalian cells, so appears highly conserved. (PMID:10931860) peripheral endoplasmic reticulum A cortical network of highly dynamic tubules that are juxtaposed to the plasma membrane and undergo ring closure and tubule-branching movements. endoplasmic reticulum tubular network