Temporal expression of the transgenic human protamine gene cluster

Abstract

Objective: To ascertain the fidelity of expression of the genes from the transgenic human sperm-specific nuclear packaging protamine-1→protamine-2→transition protein-2 (PRM1→PRM2→TNP2) locus. Design: Controlled human transgene study. Setting: Basic science laboratory. Animal(s): Age-matched transgenic and nontransgenic mice. Intervention(s): Transgenic mice containing the human protamine locus were mated. One testis from each offspring was frozen at −80°C and the other was preserved in formalin. Main Outcome Measure(s): The temporal expression of the human and mouse protamines was evaluated by Northern blot analysis. Orientation of the transgenic locus was determined by Southern blot analysis. Tissue morphology was assessed histologically. Result(s): Conservation of transgenic morphology was confirmed. Head-to-tail integration of the PRM1→PRM2→TNP2 locus was shown. Temporal expression of the mouse and human protamine genes was maintained in the transgenic state. Conclusion(s): These results show that the head-to-tail concatomer of the PRM1→PRM2→TNP2 locus contains all the necessary elements for appropriate temporal expression while maintaining testicular structure and function.