Annulate lamellae: An organelle in search of a function

Annulate lamellae are a network of intracellular membranes that have been studied for over thirty years. This membranous system of cisternae, frequently observed in rapidly dividing cells, germ cells and cells during differentiation is characterized by numerous pore-like structures that are morphologically comparable to the pore complexes of the nuclear envelope. The purpose of this review is to acquaint or reacquaint the reader with this intracellular membrane network and to address a number of basic questions concerning the origin, function, and fate of this rather intriguing cellular organelle.