Linked Life Data

19454689

Source:http://linkedlifedata.com/resource/pubmed/id/19454689

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2009-5-20
pubmed:abstractText
Several studies have reported that regulatory elements located 3' of the IgH locus (namely hs3a, hs1,2, hs3b, and hs4) might play a role during class switch recombination (CSR) and Ig synthesis. While individual deletion of hs3a or hs1,2 had no effect, pairwise deletion of hs3b (an inverted copy of hs3a) and hs4 markedly affected CSR and Ig expression. Among these two elements, hs4 was tentatively presented with the master role due to its unique status within the 3' regulatory region: distal position outside repeated regions, early activation in pre-B cells, strong activity throughout B cell ontogeny. To clarify its role, we generated mice with a clean deletion of the hs4 after replacement with a floxed neo(R) cassette. Surprisingly, and as for previous deletion of hs3a or hs1,2, deletion of hs4 did not affect either in vivo CSR or the secretion level of any Ig isotype. In vitro CSR and Ig secretion in response to LPS and cytokines was not affected either. The only noticeable effects of the hs4 deletion were a decrease in the number of B splenocytes and a decreased membrane IgM expression. In conclusion, while dispensable for CSR and Ig transcription in plasma cells, hs4 mostly appears to contribute to Ig transcription in resting B lymphocytes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1550-6606
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
182
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6926-32
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Ig synthesis and class switching do not require the presence of the hs4 enhancer in the 3' IgH regulatory region.
pubmed:affiliation
Centre National de la Recherche Scientifique Unité Mixte de Recherche 6101, Université de Limoges, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't