| Autor: |
Declan J. McKeever, Bernard Marasa, Anthony Luyai, Keith T. Ballingall |
| Rok vydání: |
2000 |
| Předmět: |
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| Zdroj: |
Major Histocompatibility Complex ISBN: 9784431658702 |
| DOI: |
10.1007/978-4-431-65868-9_21 |
| Popis: |
Full length cDNAs derived from the bovine MHC class II DQA1, DQA2, DQA3 and putative DQA4 gene loci have been cloned by RT-PCR from three MHC-homozygous Kenya Boran (Bos indicus) cattle and transiently expressed in COS-7 cells. Immunocytochemical analysis of these transfectants with a panel of monoclonal antibodies specific for bovine surface DQ revealed differential staining, which is consistent with the cDNAs encoding mature surface-expressed products. This suggests that each cDNA encodes a functional molecule capable of presenting antigens to CD4+ T cells. Analysis of genomic DNA derived from MHC-homozygous cattle (9 African B. indicus and 14 European B. taurus) revealed distinct differences in the distribution of the DQA loci. European B. taurus cattle are characterised exclusively by haplotypes containing either a single DQA1 gene or duplicated DQA1 and DQA2 genes. Although these haplotypes also occur in African B. indicus cattle, these animals also feature haplotypes that are characterised by DQA2/DQA3 or DQA2/DQA4. The apparent absence of DQA3 and DQA4 in this cohort of European B. taurus cattle may reflect the diverse evolutionary origins and environmental pressures acting on the two populations. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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