The mouse T cell receptor gamma genes

Citation

Vernooij, Bernardus Theodorus Maria (1992) The mouse T cell receptor gamma genes. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/wnmy-rm49. https://resolver.caltech.edu/CaltechTHESIS:09212011-131628448

Abstract

Murine T cells express either of 2 antigen receptors on their surface: αβ or γδ T cell receptors. The γδ T cell population contains subsets which show tissue specific localization, invariant T cell receptors and/or specificity for stress antigens. This makes these T cells unlike αβ T cells.

This thesis describes the genomic organization of the entire mouse T cell receptor gamma locus. It contains 4 clusters of gene segments, each with a C, a J and 1 to 4 V gene segments. Compared to other T cell receptor and immunoglobulin loci, this is an unusual organization. The Cγ2 cluster is in an orientation that is opposite to that of all other clusters.

Two new γ enhancer-like elements were identified in the locus. Also shown is that the hinge region of Cγ4 is encoded by at least 2 exons. This is similar to the gene organization of the human Cγ2 gene segment, and different from the other mouse and human Cγ gene segments. Sequence comparison of the T cell receptor γ gene segments of various mammals reveals structural conservation during evolution. The C region is most conserved, except in the hinge region. This subdomain is variable in length and in sequence. The extracellular domain is well conserved and contains amino acid residues which are also conserved in the other T cell receptor and immunoglobulin proteins.

The Vγ gene segments are less well conserved, but several amino acid residues are found which are (nearly) invariant. During evolution, the 2 studied mammals each appear to have lost certain V gene segments relative to a hypothetical ancestor.

Thesis Files