Molecular and biochemical characterization of the Mexican axolotl CD3 (CD3 epsilon and CD3 gamma/delta)

作者：Andre Sebastien; Kerfourn Fabienne; Fellah Julien S^*

来源：Immunogenetics, 2011, 63(12): 847-853.

DOI：10.1007/s00251-011-0560-6

• CD3
• Immunity
• Axolotl
• Evolution

In mammals, the T-cell receptor (TCR) complex expressed on mature T-cells consists of alpha/beta or gamma/delta clonotypic heterodimers non-covalently associated with four invariant chains forming the CD3 complex (CD3 gamma, CD3 delta, CD3 epsilon and CD3 zeta). The TCR is the unit implicated in the antigenic peptide recognition whereas the CD3 subunits present as three different dimers (delta-I mu, gamma-I mu and zeta-zeta) in the receptor complex participate to the signal transduction and are indispensable for the expression of the TCR at the cell surface. We report the cloning, characterization and expression analysis of CD3 gamma/delta and CD3 epsilon genes in an amphibian urodele, the Mexican axolotl. Amino acid comparisons show that important motifs and residues were preserved between the axolotl CD3 chains and various vertebrate CD3 epsilon, CD3 gamma, CD3 delta and CD3 gamma/delta chains. During ontogeny, CD3 epsilon transcripts are first detected in the dorsal region of tail-bud embryos before thymus organogenesis. CD3 gamma/delta transcripts are first detected in the head of 4-week-old larvae. A cross-reactive polyclonal anti-CD3 epsilon antibody was used for the co-immunoprecipitation of the two CD3 proteins of 25 and 29 kDa, respectively, associated with the 90-kDa alpha beta TCR heterodimer.

• 出版日期2011-12