A murine T cell receptor gene complex: isolation, structure and rearrangement

Area of Science:

• Immunology
• Molecular Biology
• Genetics

Background:

• Identifying genes for T cell-specific membrane proteins is crucial for understanding immune responses.
• The T cell receptor (TCR) is key to adaptive immunity, mediating antigen recognition.

Purpose of the Study:

• To develop a strategy for isolating genes encoding T cell-specific membrane polypeptides.
• To characterize the gene encoding the beta chain of the murine T cell receptor.

Main Methods:

• Systematic enumeration and isolation of cDNA clones.
• Sequence analysis of isolated clones to identify gene products.
• Comparison of T cell receptor gene structure with immunoglobulin genes.

Main Results:

• Isolated a cDNA clone encoding the beta chain of the murine T cell receptor.
• The TCR beta chain exhibits structural similarities to immunoglobulins, including variable (V), constant (C), joining (J), and diversity (D) elements.
• Genomic organization shows tandem JC/JC units with numerous J elements; flanking sequences resemble immunoglobulin recombination signals.

Conclusions:

• The T cell receptor beta chain gene shares evolutionary origins and recombination mechanisms with immunoglobulin genes.
• Differences in J elements and V regions suggest distinct evolutionary pressures or functional adaptations.
• The findings support the one-receptor model for MHC-antigen recognition.