Systematic variation in mRNA 3'-processing signals during mouse spermatogenesis.
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.
Liu
Donglin
D
The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA.
Brockman
J Michael
JM
Dass
Brinda
B
Hutchins
Lucie N
LN
Singh
Priyam
P
McCarrey
John R
JR
MacDonald
Clinton C
CC
Graber
Joel H
JH
D020413:3' Untranslated Regions / Q000737:chemistry; D000818:Animals; D019143:Evolution, Molecular; D020224:Expressed Sequence Tags / Q000737:chemistry; D008297:Male; D051379:Mice; D026723:Polyadenylation; D039104:RNA 3' Polyadenylation Signals; D012333:RNA, Messenger / Q000737:chemistry / Q000378:metabolism; D013091:Spermatogenesis / Q000235:genetics*; D013737:Testis / Q000378:metabolism*; D039221:mRNA Cleavage and Polyadenylation Factors / Q000378:metabolism
D020413:3' Untranslated Regions; D012333:RNA, Messenger; D039221:mRNA Cleavage and Polyadenylation Factors