The T/t-complex in the mouse: mutations that impair differentiation

Area of Science:

• Developmental biology
• Genetics
• Immunology

Background:

• The mouse T/t-complex harbors genetic factors influencing embryonic development and spermatogenesis.
• t-mutations are implicated in cell surface abnormalities, suggested by morphological, serological, and biochemical studies.

Purpose of the Study:

• To identify the molecular basis of cell surface abnormalities associated with lethal t-haplotypes.
• To investigate the nature of molecules affected by T/t-complex mutations.

Main Methods:

• Biochemical analysis to characterize molecular changes.
• Serological studies to define antigenic determinants.
• Examination of over 30 independent t-haplotypes.

Main Results:

• Identified a 63,000-dalton non-glycosylated protein as a direct gene product in mutant t-haplotypes affecting tail development.
• Demonstrated that serologically defined antigenic determinants of lethal t-haplotypes reside on different oligosaccharides.
• Found at least two distinct types of molecules associated with complex lethal t-haplotypes.

Conclusions:

• T/t-complex mutations affect distinct molecular entities, including proteins and carbohydrates, at the cell surface.
• These findings provide insights into the arrangement and function of mutant factors within the T/t-complex.
• The study highlights the molecular heterogeneity underlying T/t-complex associated developmental defects.