|
|
|
|
|
|
|
||
The Journal of Cell Biology, Vol 109, 1439-1444, Copyright © 1989 by The Rockefeller University Press
ARTICLES |
A Ceriotti and A Colman
Department of Biochemistry, University of Birmingham, United Kingdom.
We have previously shown that Xenopus oocytes arrested at second meiotic metaphase lost their characteristic multicisternal Golgi apparati and cannot secrete proteins into the surrounding medium. In this paper, we extend these studies to ask whether intracellular transport events affecting the movement of secretory proteins from the endoplasmic reticulum to the Golgi apparatus are also similarly inhibited in such oocytes. Using the acquisition of resistance to endoglycosidase H (endo H) as an assay for movement to the Golgi, we find that within 6 h, up to 66% of the influenza virus membrane protein, hemagglutinin (HA), synthesized from injected synthetic RNA, can move to the Golgi apparati in nonmatured oocytes; indeed after longer periods some correctly folded HA can be detected at the cell surface where it distributes in a nonpolarized fashion. In matured oocytes, up to 49% of the HA becomes endo H resistant in the same 6-h period. We conclude that movement from the endoplasmic reticulum to the Golgi can occur in matured oocytes despite the dramatic fragmentation of the Golgi apparati that we observe to occur on maturation. This observation of residual protein movement during meiotic metaphase contrasts with the situation at mitotic metabphase in cultured mammalian cells where all movement ceases, but resembles that in the budding yeast Saccharomyces cerevisiae where transport is unaffected.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Facebook 
Reddit 
Technorati 
Twitter What's this?
This article has been cited by other articles:
|
|
