Regulation of salivary-gland-specific gene expression.
The results from in vivo transgenic and in vitro transfection studies designed to identify cis-element(s) and transfactor(s) governing the salivary proline-rich proteins (PRPs), amylase, and parotid secretory protein (PSP) gene expression are utilized as a paradigm to discuss the regulation of salivary-specific gene expression. Particular attention is given to the molecular mechanism(s) underlying the salivary PRP R15 gene regulation. In rodents, the PRPs are selectively expressed in the acinar cells of salivary glands, and are inducible by the beta-agonist isoproterenol and by dietary tannins. The results from a series of experiments using chimeric reporter constructs containing different lengths of the R15 distal enhancer region, their mutations, and various expressing constructs are analyzed and discussed. These data suggest that the inducible nuclear orphan receptor NGFI-B may participate in the regulation of salivary acinar-cell-specific and inducible expression of the rat R15 gene via three distinct distal NGFI-B sites. Taken together, a model for the induction of R15 gene expression by Ipr is proposed. However, the exact molecular basis of this NGFI-B-mediated transactivation of cAMP-regulated R15 expression remains to be established.
Ann
D K
DK
Department of Molecular Pharmacology and Toxicology, University of Southern California-HSC, Los Angeles 90033, USA.
Lin
H H
HH
Kousvelari
E
E
D000681:Amylases / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D000242:Cyclic AMP / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D008957:Models, Genetic; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D010455:Peptides / Q000235:genetics* / Q000378:metabolism; D055232:Proline-Rich Protein Domains; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D012469:Salivary Glands / Q000254:growth & development / Q000378:metabolism*; D012471:Salivary Proteins and Peptides / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D015533:Transcriptional Activation
C511598:Bpifa2 protein, rat; D004268:DNA-Binding Proteins; C539820:Nr4a1 protein, rat; D057105:Nuclear Receptor Subfamily 4, Group A, Member 1; D010455:Peptides; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D012471:Salivary Proteins and Peptides; D014157:Transcription Factors; D000242:Cyclic AMP; D000681:Amylases