Quantification of endocytosis-derived membrane traffic

摘要: The main data covered by this article have been summarized in Table I. A fairly uniform picture is obtained for endocytosis-derived membrane transfer and compartmentation. This may be due to the limited amount of information resulting low resolution. Data on mainly three cell types are presented: macrophages, fibroblasts amoebae. vary as much one type between different cells. Therefore, no possible differences related function emerge. More detailed data, more types, change picture. values surface area, although significantly absolute terms (column S I), rather similar when diameter, all being about 3-fold excess area smooth sphere comparable volume xi I). rate plasma internalization macrophages amoebae both professional phagocytes, 2 equivalents per h or more. somewhat higher than PM/h average residence time surface, therefore, 30 min. most interesting finding seems size (volume weighted) primary pinosomes, 0.3 micron diameter phi-Internalization Due their rapid increase a result fusion (cf. Fig. 2), it has not feasible directly measure pinosomes morphometric means. I, give distributions whether these consist classes. steady-state noticeably larger that phi-pinosomes I; cf. II Acanthamoebae). corresponding decrease surface-to-volume ratio can make 50% pinosomal available recycling from compartment. Membrane compartment occurs after an 3 min 4-6 tau-pinosomes relative pool intracellular membranes participating shuttling animal cells rho For fibroblasts, CHO cells, mast amounts 10-20% compared 150-200% case amoebae.(ABSTRACT TRUNCATED AT 400 WORDS)