ANALYSIS OF THE MOUSE PROTAMINE-1 PROMOTER IN TRANSGENIC MICE

Protamines are small arginine-rich proteins that package DNA in sperma tozoa. The mouse protamine 1 (Prm-1) gene is transcribed exclusively i n post-meiotic spermatids. To identify elements in the Prm-1 promoter required for spermatid-specific transcription, we generated transgenic mice by microinjection of transgenes containing Prm-1 5' flanking seq uences with 5' truncations or internal deletions of conserved sequence s linked to a marked Prm-1 gene. We also tested Prm-1 promoter regions with a heterologous human growth hormone reporter gene. We conclude t hat a 113-bp region can direct spermatid-specific transcription and we have defined sequences within this region that are essential for prop er function. These results will facilitate the isolation and character ization of transcription factors essential for post-meiotic gene expre ssion.