Induction of annulate lamellae by alpha-difluoromethylornithine in P3J, a Burkitt's lymphoma cell line.

Annulate lamellae form in P3J, a Burkitt's lymphoma cell line, treated with alpha-difluoromethylornithine (DFMO), an inhibitor of polyamine synthesis. DFMO (50-100 micrograms/ml) prevents proliferation although cells remain viable. Upon exposure to DFMO, lamellae with a few pores form within 2-3 days and well-developed stacks of annulate lamellae in 5-6 days. Formation of annulate lamellae involves the addition of electron-dense fibrous material to cisternae of the endoplasmic reticulum while the latter are in close association with the Golgi complex. Addition of the polyamine putrescine to DFMO-treated cells reverses the inhibition of cell proliferation caused by DFMO. Following recovery from DFMO treatment, P3J cells appear similar to untreated ones in that they do not possess stacks of annulate lamellae.