Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-2-12
pubmed:abstractText
The human complement component 4 is encoded in two genes, C4A and C4B, residing between the class I and class II genes of the major histocompatibility complex. The C4A and C4B molecules differ in their biological activity, the former binding more efficiently to proteins than to carbohydrates while for the latter, the opposite holds true. To shed light on the origin of the C4 genes we isolated cosmid clones bearing the C4 genes of a chimpanzee, a gorilla, and an orang-utan. From the clones, we isolated the fragments coding for the C4d part of the gene (exons and introns) and sequenced them. Altogether we sequenced eight gene fragments: three chimpanzee (Patr-C4-1*01, Patr-C4-1*02, Patr-C4-2*01), two gorilla (Gogo-C4-1*01, Gogo-C4-2*01), and three orang-utan (Popy-C4-1*01, Popy-C4-2*01, Popy-C4-3*01). Comparison of the sequences with each other and with human C4 sequences revealed that in the region believed to be responsible for the functional difference between the C4A and C4B proteins the C4A genes of the different species fell into one group and the C4B genes fell into another. In the rest of the sequence, however, the C4A and C4B genes of each species resembled each other more than they did C4 genes of other species. These results are interpreted as suggesting extensive homogenization (concerted evolution) of the C4 genes in each species, most likely by repeated unequal, homologous, intragenic crossing-over.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0093-7711
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:geneSymbol
C4, C4A1, C4A3, C4A4, C4B1a, C4B1b, C4B2, C4B5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16-23
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
C4 genes of the chimpanzee, gorilla, and orang-utan: evidence for extensive homogenization.
pubmed:affiliation
Max-Planck-Institut für Biologie, Abteilung Immungenetik, Tübingen, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't