title: Simian virus 40-rabbit beta-globin recombinants lacking late mRNA splice sites express cytoplasmic RNAs with altered structures.
abstract: Deletions were introduced at exon-intron boundaries in the late region of a simian virus 40-beta-globin cDNA recombinant to study the role of splicing in the formation of simian virus 40 late cytoplasmic RNAs. The recombinant was used as a wild type because it allowed characterization of mutant RNAs expressed from defective genomes in the presence of comparable RNAs contributed by the coinfecting helper virus. Removal of a 17-base pair segment at map position 0.76, which included a portion of the leader sequence implicated in the splicing of the major 16S mRNA, prevented expression of 16S-type mRNA. The same mutant accumulated cytoplasmic 19S-type mRNA, but the assortment of the 5' ends of these mRNAs differed from the assortment of the wild-type counterparts. Another mutant that lacks nucleotide sequences implicated in the splicing of the major 16S mRNA and one of the principal 19S-type RNAs accumulated a 16S-type mRNA with a previously undetected leader splice, and assortment of 19S mRNAs with new or normally underrepresented splices, and even a species of unspliced cytoplasmic 19S mRNA.
mesh_terms: D000818:Animals; D001483:Base Sequence; D004274:DNA, Recombinant; D003673:Defective Viruses / Q000235:genetics; D005914:Globins / Q000096:biosynthesis / Q000235:genetics*; D006378:Helper Viruses / Q000235:genetics; D009693:Nucleic Acid Hybridization; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics*; D011817:Rabbits; D013539:Simian virus 40 / Q000235:genetics*
chemical_list: D004274:DNA, Recombinant; D012333:RNA, Messenger; D012367:RNA, Viral; D005914:Globins