Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2002-5-16
pubmed:abstractText
Under fresh-water cultivation conditions, spermatogenesis in the Japanese eel is arrested at an immature stage before initiation of spermatogonial proliferation. A single injection of human chorionic gonadotropin can, however, induce complete spermatogenesis, which suggests that spermatogenesis-preventing substances may be present in eel testis. To determine whether such substances exist, we have applied a subtractive hybridisation method to identify genes whose expression is suppressed after human chorionic gonadotropin treatment in vivo. We found one previously unidentified cDNA clone that was downregulated by human chorionic gonadotropin, and named it 'eel spermatogenesis related substances 21' (eSRS21). A homology search showed that eSRS21 shares amino acid sequence similarity with mammalian and chicken Müllerian-inhibiting substance. eSRS21 was expressed in Sertoli cells of immature testes, but disappeared after human chorionic gonadotropin injection. Expression of eSRS21 mRNA was also suppressed in vitro by 11-ketotestosterone, a spermatogenesis-inducing steroid in eel. To examine the function of eSRS21 in spermatogenesis, recombinant eSRS21 produced by a CHO cell expression system was added to a testicular organ culture system. Spermtogonial proliferation induced by 11-ketotestosterone in vitro was suppressed by recombinant eSRS21. Furthermore, addition of a specific anti-eSRS21 antibody induced spermatogonial proliferation in a germ cell/somatic cell co-culture system. We conclude that eSRS21 prevents the initiation of spermatogenesis and, therefore, suppression of eSRS21 expression is necessary to initiate spermatogenesis. In other words, eSRS21 is a spermatogenesis-preventing substance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0950-1991
pubmed:author
pubmed:issnType
Print
pubmed:volume
129
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2689-97
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:12015296-Amino Acid Sequence, pubmed-meshheading:12015296-Animals, pubmed-meshheading:12015296-CHO Cells, pubmed-meshheading:12015296-Chickens, pubmed-meshheading:12015296-Cloning, Molecular, pubmed-meshheading:12015296-Cricetinae, pubmed-meshheading:12015296-DNA, Complementary, pubmed-meshheading:12015296-Eels, pubmed-meshheading:12015296-Gene Expression Regulation, Developmental, pubmed-meshheading:12015296-Humans, pubmed-meshheading:12015296-Male, pubmed-meshheading:12015296-Mice, pubmed-meshheading:12015296-Molecular Sequence Data, pubmed-meshheading:12015296-RNA, Messenger, pubmed-meshheading:12015296-Recombinant Proteins, pubmed-meshheading:12015296-Sequence Alignment, pubmed-meshheading:12015296-Sequence Homology, Amino Acid, pubmed-meshheading:12015296-Spermatogenesis, pubmed-meshheading:12015296-Spermatogonia, pubmed-meshheading:12015296-Transcription, Genetic, pubmed-meshheading:12015296-Transfection
pubmed:year
2002
pubmed:articleTitle
Spermatogenesis-preventing substance in Japanese eel.
pubmed:affiliation
Marine Bioresources Research Group, Field Science Center for Northern Biosphere, Hokkaido University, Hakodate 041-8611, Japan. takeshi@fish.hokudai.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't