Drosophila clipper/CPSF 30K is a post-transcriptionally regulated nuclear protein that binds RNA containing GC clusters.
An essential component of the mammalian pre-mRNA 3'-end processing machinery is a multimeric protein complex known as cleavage and polyadenylation specificity factor (CPSF). The Drosophila melanogaster gene, clipper ( clp ), encodes a homolog of the CPSF 30K subunit. We have shown previously that CLP possesses N-terminal endoribonucleolytic activity and that the relative expression of its mRNA fluctuates during fly development. In the present study, we report that CLP's C-terminus, containing two CCHC zinc knuckles, confers a binding preference for RNAs that contain G- and/or C-rich clusters. We also show, for the first time, that a member of the highly conserved CPSF 30K family is a nuclear and developmentally regulated protein. Though clp transcripts are detectable throughout embryogenesis, CLP protein is not present. We demonstrate that post-transcriptional regulation of clp mRNA in the embryo occurs by a process that does not involve poly(A) tail length shortening. Thus, a key component of the pre-mRNA 3'-end processing machinery is subject to post-transcriptional regulation during development. These results support the existence of a distinct mechanism controlling eukaryotic gene expression through the regulated processing of pre-mRNAs in the nucleus.
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D000595:Amino Acid Sequence; D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D003596:Cytosine; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development*; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D006147:Guanine; D007814:Larva; D051379:Mice; D008969:Molecular Sequence Data; D012322:RNA Precursors / Q000737:chemistry / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000096:biosynthesis; D016601:RNA-Binding Proteins / Q000096:biosynthesis* / Q000737:chemistry; D016415:Sequence Alignment; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013379:Substrate Specificity; D014158:Transcription, Genetic; D015027:Zebrafish; D016335:Zinc Fingers; D039221:mRNA Cleavage and Polyadenylation Factors
D012322:RNA Precursors; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D006147:Guanine; D003596:Cytosine