Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-9-21
pubmed:abstractText
The mechanisms underlying cell cycle progression and differentiation are tightly entwined with changes associated in the structure and composition of the cytoskeleton. Mammalian spermatogenesis is a highly intricate process that involves differentiation and polarization of the round spermatid. We found that pachytene spermatocytes and round spermatids have most of the microtubules randomly distributed in a cortical network without any apparent centrosome. The Golgi apparatus faces the acrosomal vesicle and some microtubules contact its surface. In round spermatids, at step 7, there is an increase in short microtubules around and over the nucleus. These microtubules are located between the rims of the acrosome and may be the very first sign in the formation of the manchette. This new microtubular configuration is correlated with the beginning of the migration of the Golgi apparatus from the acrosomal region towards the opposite pole of the cell. Next, the cortical microtubules form a bundle running around the nucleus perpendicular to the main axis of the cell. At later stages, the nuclear microtubules increase in size and a fully formed manchette appears at stage 9. On the other hand, acetylated tubulin is present in a few microtubules in pachytene spermatocytes and in the axial filament (precursor of the sperm tail) in round spermatids. Our results suggest that at step 7, the spermatid undergoes a major microtubular reordering that induces or allows organelle movement and prepares the cell for the formation of the manchette and further nuclear shaping. This new microtubular configuration is associated with an increase in short microtubules over the nucleus that may correspond to the initial step of the manchette formation. The new structure of the cytoskeleton may be associated with major migratory events occurring at this step of differentiation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0886-1544
pubmed:author
pubmed:copyrightInfo
Copyright 2000 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
235-46
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Microtubule configurations and post-translational alpha-tubulin modifications during mammalian spermatogenesis.
pubmed:affiliation
Oregon Regional Primate Research Center, Oregon Health Sciences University, Beaverton, OR 97006, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.