Modulation of proline-rich protein biosynthesis in rat parotid glands by sorghums with high tannin levels.
Feeding of sorghum with a high level of tannin (high-tannin sorghum) to rats caused changes in gene expression in parotid glands similar to isoproterenol treatment. Within 3 days the parotid glands were enlarged about 3-fold and a series of proline-rich proteins were increased about 12-fold. Unlike isoproterenol treatment, no changes were observed in the submandibular glands, and a Mr 220,000 glycoprotein in parotid glands was not induced. Amino acid analyses, electrophoretic patterns, and cell-free translations of mRNAs all confirmed that the proline-rich proteins induced by feeding high-tannin sorghum were identical to those induced by isoproterenol treatment. Binding curves for proline-rich proteins to tannins showed affinities 10-fold greater than bovine serum albumin and tannins.
D000818:Animals; D004032:Diet; D002523:Edible Grain; D007700:Kinetics; D008297:Male; D008970:Molecular Weight; D009928:Organ Specificity; D010306:Parotid Gland / Q000187:drug effects / Q000378:metabolism*; D010455:Peptides / Q000235:genetics*; D055232:Proline-Rich Protein Domains; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D011919:Rats, Inbred Strains; D012471:Salivary Proteins and Peptides / Q000235:genetics*; D013363:Submandibular Gland / Q000378:metabolism; D013634:Tannins / Q000494:pharmacology*; D014158:Transcription, Genetic / Q000187:drug effects*
D010455:Peptides; D012333:RNA, Messenger; D012471:Salivary Proteins and Peptides; D013634:Tannins