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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1984-7-30
pubmed:abstractText
A histochemical, microdensitometric, and electron microscopic study of testes of the ratfish Hydrolagus colliei shows that an instance of the rare phenomenon of germ line chromatin diminution occurs in this vertebrate species. In primary spermatocytes at metaphase I a spherical mass of heterochromatin accumulates at one side of the metaphase plate. At anaphase I the heterochromatic mass is left in the equatorial cytoplasm and is passed into one of the two secondary spermatocytes formed during cytokinesis. As nuclear membranes are being restored, a double membrane envelope is also formed around the heterochromatic mass, which is then termed the 'chromatin diminution body' (CDB). At second meiotic division the CDB is included in the cytoplasm of one of the four spermatids and retained there, apparently unchanged, until mid-spermiogenesis. At that time the CDB becomes adherent to the spermatid plasma membrane and is pinched off from the spermatid by a process of apocrine exocytosis, taking a layer of spermatid plasma membrane along with it. Simultaneously this tri-membrane CDB is taken into the adjacent Sertoli cell by endocytosis, thereby acquiring a fourth membrane layer, a part of the Sertoli cell plasma membrane. The CDBs are subsequently phagocytized, possibly first fusing with dense, multilaminate bodies in the Sertoli cell cytoplasm. The CDB chromatin mass is strongly positive with the Feulgen method for DNA and the alkaline fast green method for histones. Microdensitometric analysis shows that the discarded chromatin amounts to about 10% of the diploid nuclear content and that it appears to be part of the normal diploid complement rather than DNA amplified during meiosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0040-8166
pubmed:author
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
203-15
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Meiotic chromatin diminution in a vertebrate, the holocephalan fish Hydrolagus collie (Chondrichthyes, Holocephali).
pubmed:publicationType
Journal Article