|Karsi, A - MISS. STATE UNIV.|
Submitted to: Animal Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 7, 2004
Publication Date: February 27, 2004
Citation: Karsi, A., Waldbieser, G.C. 2004. Partial cloning of t-cell receptor alpha (TCRa) gene and assignment to TCRa and TCRb genes to the catfish linkage map. Animal Genetics 35:150-151. Interpretive Summary: T-cell receptors are molecules involved in the cellular recognition of foreign antigens and immune response. In order to identify potential genetic variation correlated with disease resistance in channel catfish, variable DNA regions, termed microsatellites, were identified in two receptor genes, TCR alpha and TCR beta. Analysis of these regions revealed DNA sequence variation in catfish populations. The microsatellite regions were also used to place these T-cell receptor genes on the catfish genetic linkage map. Addition of conserved genes to the catfish linkage map will facilitate comparative analyses with other genomes. The microsatellite loci will also assist researchers in the identification of genetic variation correlated with increased resistance to disease.
Technical Abstract: Polymorphic microsatellite marker sequences were identified in DNA sequences proximal to the T-cell receptor alpha and beta genes. A catfish bacterial artificial chromosome clone containing the TCR alpha gene was partially sequenced to obtain the last four introns and exons of this gene. STRAP sequencing with a tandem repeat primer was used to identify a microsatellite locus in this clone. A microsatellite locus was identified in the sequence of the TCRß gene already in the GenBank public database. Amplification of these microsatellites in genomic DNA revealed sequence polymorphism in catfish populations, and this can be used to assess correlation of TCR alleles with specific phenotypes. The microsatellite markers were also used to place these T-cell receptor genes on the catfish genetic linkage map. The TCR alpha gene was located at one terminal of the 93.2 cM linkage group U18. The TCR beta gene was located 17cM from one terminal of the 73.7cM linkage group U13. Addition of conserved genes to the catfish linkage map facilitates comparative analyses with other genomes.