Systematic variation in mRNA 3'-processing signals during mouse spermatogenesis

• Published in: Nucleic acids research 2007-01, Vol.35 (1), p.234-246
• Main Authors: Liu, Donglin, Brockman, J. Michael, Dass, Brinda, Hutchins, Lucie N, Singh, Priyam, McCarrey, John R, MacDonald, Clinton C, Graber, Joel H
• Format: Article
• Language: English
• Subjects: 3' Untranslated Regions - chemistry; Animals; Computational Biology; Evolution, Molecular; Expressed Sequence Tags - chemistry; Male; Mice; mRNA Cleavage and Polyadenylation Factors - metabolism; Polyadenylation; RNA 3' Polyadenylation Signals; RNA, Messenger - chemistry; RNA, Messenger - metabolism; Spermatogenesis - genetics; Testis - metabolism
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/gkl919

Gene expression and processing during mouse male germ cell maturation (spermatogenesis) is highly specialized. Previous reports have suggested that there is a high incidence of alternative 3′-processing in male germ cell mRNAs, including reduced usage of the canonical polyadenylation signal, AAUAAA. We used EST libraries generated from mouse testicular cells to identify 3′-processing sites used at various stages of spermatogenesis (spermatogonia, spermatocytes and round spermatids) and testicular somatic Sertoli cells. We assessed differences in 3′-processing characteristics in the testicular samples, compared to control sets of widely used 3′-processing sites. Using a new method for comparison of degenerate regulatory elements between sequence samples, we identified significant changes in the use of putative 3′-processing regulatory sequence elements in all spermatogenic cell types. In addition, we observed a trend towards truncated 3′-untranslated regions (3′-UTRs), with the most significant differences apparent in round spermatids. In contrast, Sertoli cells displayed a much smaller trend towards 3′-UTR truncation and no significant difference in 3′-processing regulatory sequences. Finally, we identified a number of genes encoding mRNAs that were specifically subject to alternative 3′-processing during meiosis and postmeiotic development. Our results highlight developmental differences in polyadenylation site choice and in the elements that likely control them during spermatogenesis.