Formation of rough endoplasmic reticulum and nuclear membrane in normal and tumour cells.

Paired cisternae have been found in normal and tumour cells both at interphase and mitosis being more common at the latter. It is believed that newly synthesized membranous protein and phospholipid molecules in the cisternae may polymerize spontaneously to form new membranes and as a consequence, multiplication of endoplasmic reticulum and nuclear membrane occur. Thus paired cisternae in interphase and mitotic cells may serve as a centre for the organisation of these two cellular organelles.