title: cDNA cloning of human hnRNP protein A1 reveals the existence of multiple mRNA isoforms.
abstract: Protein A1 is one of the major component of mammalian ribonucleoprotein particles (hnRNP). Human protein A1 cDNA cloning and sequencing revealed the existence of at least two protein isoforms. Among the cDNAs examined, sequence differences were found both in the structural portion, leading to aminoacid changes (Tyr to Phe or Arg to Lys) and in the non translated 3'-region where two T-stretches of different length were observed. Interestingly one of the aminoacid substitutions falls into a consensus sequence common to many RNA binding proteins. Northern blot analysis of poly A+ RNAs from five human tissues revealed two mRNA forms of 1500 and 1900 n due to alternative polyadenylation. Analysis of genomic DNA showed at least 30 A1-specific sequences, some of which correspond to processed pseudogenes. These results suggest that protein A1 is encoded by a multigene family.
authors.affiliation: Istituto di Genetica Biochimica ed Evoluzionistica, CNR, Pavia, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Buvoli
authors.forename: G
authors.initials: G
authors.lastname: Biamonti
authors.forename: P
authors.initials: P
authors.lastname: Tsoulfas
authors.forename: M T
authors.initials: MT
authors.lastname: Bassi
authors.forename: A
authors.initials: A
authors.lastname: Ghetti
authors.forename: S
authors.initials: S
authors.lastname: Riva
authors.forename: C
authors.initials: C
authors.lastname: Morandi
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004262:DNA Restriction Enzymes; D005796:Genes; D014644:Genetic Variation; D000076245:Heterogeneous Nuclear Ribonucleoprotein A1; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D006801:Humans; D008969:Molecular Sequence Data; D009710:Nucleotide Mapping; D009928:Organ Specificity; D012333:RNA, Messenger / Q000235:genetics*; D012261:Ribonucleoproteins / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D000076245:Heterogeneous Nuclear Ribonucleoprotein A1; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D012333:RNA, Messenger; D012261:Ribonucleoproteins; D004247:DNA; D004262:DNA Restriction Enzymes