cDNA clones for mouse parotid proline-rich proteins. mRNA regulation by isoprenaline and the nucleotide sequence of proline-rich protein cDNA MP5.
cDNA clones for mRNA sequences regulated by isoprenaline in mouse parotid glands were identified by differential colony hybridisation and all hybridised to a diagnostic proline-rich protein (PRP) oligonucleotide. They were divided into two cross-hybridisation groups, A and B, which were shown by hybrid-selected translations to encode acidic PRP and basic PRP, respectively. The A-type subgroup consisted of sequences homologous to the previously identified mouse PRP genes MP2 and MP3. The B-type subgroup comprised clones for the previously identified cDNA pUMP125 (MP4) as well as other PRP sequences. Six of the B-type clones contained a novel PRP cDNA (MP5) and these were sequenced. The composite MP5 cDNA was 897 nucleotides long and contained an open reading frame capable of encoding a 260-residue-long salivary PRP precursor (30% Pro, 19% Gln and 18% Gly), containing nine variant repeat units of consensus PGNQQGPPPQGGPQQ(GPP)R(PPQ). MP5 was 80% identical to the sequence of MP4 and had a high degree of similarity (60%) at its 3'-untranslated region to rat salivary glutamate/glutamine-rich protein (GRP) cDNA. Two MP5 clones contained a 273-bp intron-like insertion in the 3' untranslated region, being derived, therefore, from incompletely spliced MP5 transcripts. Northern blotting showed that, although PRP mRNA species were induced by isoprenaline, a B-type PRP mRNA was present in normal parotid glands. RNA dot-blots probed with PRP-gene-specific oligonucleotides established that MP3, MP4 and MP5 PRP mRNA were all induced by isoprenaline.
Layfield
R
R
Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, England.
Bannister
A J
AJ
Pierce
E J
EJ
McDonald
C J
CJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D004247:DNA / Q000235:genetics*; D004591:Electrophoresis, Polyacrylamide Gel; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes; D016366:Open Reading Frames; D010306:Parotid Gland / Q000378:metabolism*; D010455:Peptides / Q000235:genetics*; D010957:Plasmids; D055232:Proline-Rich Protein Domains; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics*; D016415:Sequence Alignment
D015345:Oligonucleotide Probes; D010455:Peptides; D012333:RNA, Messenger; D004247:DNA; D007545:Isoproterenol