Small proline-neh protein, sprl, gene is e \piessed predominately in squamous epithelial tissues. We have previously demonstrated that the expression of sprl gene in non-squamoiis tissues, such as conducting airway epithelium could be elevated by agents- that stimulate squamous cell differentiation. Both nuelear run-on and reporter i "instruct trän s fee 11 on studies have suggested a Iran script ion a t mechanism involved m the regulation of squamous cell type-specific sprl gene expression. To further elueidate the nature of the mechanism, transgenic mice carrying the -622 bp of human sprl gene -4'Hanking region and the reporter gene, ehloramphemcol acetyltransl'erase (CAT) were generated. Using the immunohistochemistry technique, antigens specilic to anti-CA'I' and anti-sprl antibodies were co-loeali/cd in various squamous tissues. In conducting airwavs. the expression of CAT and sprl were lower than those know squamous tissues, hut the levels were detectable. Using the primary culture of mouse trachéal epithelial cells, we were able to demonstrate an elevation of CAT and sprl gene expression by the agent, 12-0-teira- decanoylphorbol-13-acelate (TPA). knowingly invoked m stimulation of squamous cell differentiation of airway epithelial cells. In contrast. other non-squamous tissues had no expression of both CAT- and sprl -like antigens in transgenitj mice. To further elucidate the DNA fragment of the 5" tlankmg legion that is responsible for this tissue-specific expression, transgenic mice earning shorter DNA fragment of -162 bp of sprl 5flanking region were generated. ÇA F activity was drastically decreased in squamous tissues of these transgenic mice, however, the level ol'the CAT activity in conducting airway remain unchanged. These results suggest that the -162 bp of sprl gene 5'Hanking region contains the ciselements that are involved m the regulation ol'the squamous cell marker, sprl. gt-ne expression m conducting airway epithelium.
|Original language||English (US)|
|State||Published - 1997|
ASJC Scopus subject areas
- Agricultural and Biological Sciences (miscellaneous)
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology