Alpha1 and alpha2 domains of Aotus MHC class I and Catarrhini MHC class Ia share similar characteristics

C F Suárez1, P P Cárdenas, E J Llanos-Ballestas

  • 1Fundación Instituto de Inmunología de Colombia, FIDIC, Bogotá, Colombia. carlos_suarez@fidic.org.co

Tissue Antigens
|May 20, 2003
PubMed

Functional and structural analyses of major histocompatibility complex (MHC) class I molecules of the Aotus genus are necessary to validate it as a solid animal model for biomedical research. We thus isolated, cloned and sequenced exons 2 and 3 from three Aotus species (A. nancymaae, A. nigriceps and A. vociferans). We found 24 sequences, which divided into two different groups (Ao-g1 and Ao-g2). A further sequence was identified as a processed pseudogene (Aona-PS2). Both sequence evolution and variability analyses showed that Ao-g1 and Ao-g2 display similar characteristics to Catarrhini's classical loci, such as positive selection pressure at the peptide binding region (PBR) high variability and a trans-specific evolution pattern.

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