title: The human U1-70K snRNP protein: cDNA cloning, chromosomal localization, expression, alternative splicing and RNA-binding.
abstract: We have isolated and sequenced cDNA clones encoding the human U1-70K snRNP protein, and have mapped this locus (U1AP1) to human chromosome 19. The gene produces two size classes of RNA, a major 1.7-kb RNA and a minor 3.9-kb RNA. The 1.7-kb species appears to be the functional mRNA; the role of the 3.9-kb RNA, which extends further in the 5' direction, is unclear. The actual size of the hU1-70K protein is probably 52 kd, rather than 70 kd. The protein contains three regions similar to known nucleic acid-binding proteins, and it binds RNA in an in vitro assay. Comparison of the cDNA sequences indicates that there are multiple subclasses of mRNA that arise by alternative pre-mRNA splicing of at least four alternative exon segments. This suggests that multiple forms of the hU1-70K protein may exist, possibly with different functions in vivo.
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002874:Chromosome Mapping; D002888:Chromosomes, Human, Pair 19; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D000939:Epitopes; D005786:Gene Expression Regulation; D006801:Humans; D008969:Molecular Sequence Data; D011485:Protein Binding; D012313:RNA / Q000378:metabolism; D012326:RNA Splicing; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012261:Ribonucleoproteins / Q000235:genetics* / Q000276:immunology; D017411:Ribonucleoproteins, Small Nuclear
chemical_list: D000939:Epitopes; D011993:Recombinant Fusion Proteins; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D012313:RNA; D004247:DNA