Potential regulatory sequences in the untranslated regions of the baboon MHC class Ib gene, Paan-AG, more closely resemble those in the human MHC class Ia genes than those in the class Ib gene, HLA-G

Immunogenetics. 2004 Dec;56(9):657-66. doi: 10.1007/s00251-004-0727-5. Epub 2004 Nov 17.

Abstract

The baboon major histocompatibility complex (MHC) class Ib gene, Paan-AG, is structurally similar to the human MHC class Ia gene, HLA-A, but exhibits characteristics similar to those of the class Ib gene HLA-G. These include limited polymorphism, alternative splicing of a single message, and restricted tissue distribution, with high expression in the placenta. In order to determine whether regulatory elements controlling expression of Paan-AG resemble those of HLA-A or HLA-G, we cloned the 5' and 3' untranslated regions of Paan-AG. Unexpectedly, sequence comparisons showed that potential regulatory elements in Paan-AG strikingly resembled those in HLA-A and differed in major respects from those in HLA-G. Unlike HLA-G, Paan-AG contained an intact interferon-gamma stimulated response element (ISRE) in the promoter. Studies using luciferase reporter assays showed that the Paan-AG ISRE was functional. The basal activity of the Paan-AG ISRE and its response to interferon-gamma was similar to that of class Ia MHC genes. Further, we identified an ISRE in the 3' untranslated region of Paan-AG that is known to be functional in HLA-A2 but is deleted in HLA-G. These experiments predict that functional studies may demonstrate differences in regulation of expression of Paan-AG and HLA-G genes, which could restrict the use of the baboon as a primate model for studying HLA-G expression and function.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Enhancer Elements, Genetic
  • Genes, Reporter
  • HLA Antigens / genetics*
  • HLA-G Antigens
  • Histocompatibility Antigens Class I / genetics*
  • Humans
  • Mice
  • Molecular Sequence Data
  • Papio / genetics*
  • Papio / immunology
  • Polymerase Chain Reaction
  • Promoter Regions, Genetic
  • Response Elements
  • Untranslated Regions / genetics*

Substances

  • HLA Antigens
  • HLA-G Antigens
  • Histocompatibility Antigens Class I
  • Untranslated Regions

Associated data

  • GENBANK/AY434095
  • GENBANK/AY434096
  • GENBANK/AY434097
  • GENBANK/AY434103