Identification of the Rhesus Monkey HLA-G Ortholog: Mamu-G is a Pseudogene

Jonathan E. Boyson, Kristen K. Iwanaga, Thaddeus G. Golos, David I. Watkins

Research output: Contribution to journalArticle

60 Scopus citations

Abstract

HLA-G is a nonclassical MHC class I molecule that is primarily expressed in the placenta. To investigate whether rhesus monkeys possess an HLA-G ortholog, we cloned and sequenced MHC class I cDNAs from the rhesus placenta. We identified two rhesus MHC class I cDNAs with sequence similarity to HLA-G. Each cDNA contained premature stop codons and frameshift mutations, suggesting that it was derived from an MHC class I pseudogene. Gene trees constructed using MHC class I alleles from human and nonhuman primates revealed that the rhesus placental pseudogene alleles clustered with HLA-G orthologs from the human, chimpanzee, and gorilla. These data suggested that this rhesus MHC class I pseudogene is an HLA-G ortholog. This locus was, therefore, designated Mamu (Macaca mulatta)-G. PCR amplification of a portion of Mamu-G from the genomic DNA of five rhesus monkeys resulted in the identification of five additional Mamu-G alleles and revealed the presence of four Mamu-G alleles in one rhesus monkey, suggesting that Mamu-G had been duplicated in this individual. Furthermore, the analysis of 81 MHC class I clones isolated from a rhesus placenta cDNA library did not result in the isolation of Mamu-G cDNAs, nor the isolation of any additional HLA-G homologs, suggesting that Mamu-G was transcribed at negligible levels. Given the similarity of rhesus monkey and human placenta structure and function, these data raise interesting questions regarding the role of HLA-G in pregnancy.

Original languageEnglish (US)
Pages (from-to)5428-5437
Number of pages10
JournalJournal of Immunology
Volume157
Issue number12
StatePublished - Dec 15 1996

    Fingerprint

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Cite this

Boyson, J. E., Iwanaga, K. K., Golos, T. G., & Watkins, D. I. (1996). Identification of the Rhesus Monkey HLA-G Ortholog: Mamu-G is a Pseudogene. Journal of Immunology, 157(12), 5428-5437.