title: Cell-cell contact and cAMP regulate the expression of a UDP glucose pyrophosphorylase gene of Dictyostelium discoideum.
abstract: UDP glucose pyrophosphorylase (UDPGP) (EC.2.7.7.9) is a developmentally regulated enzyme of Dictyostelium discoideum. Two polypeptides of UDPGP are translated from Dictyostelium mRNA. Recently we isolated a cDNA clone which encodes one of the UDPGP polypeptides (B. R. Fishel, J. A. Ragheb, A. Rajkovic, B. Haribabu, C. W. Schweinfest, and R. P. Dottin (1985). Dev. Biol. 110, 369-381). By hybridization with the cDNA and by in vitro translation and immunoprecipitation, we examined the effect of cell-cell contact and cAMP on the regulation of UDPGP expression. Disaggregation of slugs resulted in a rapid loss of UDPGP mRNA. Addition of cAMP to these cells resulted in increased levels of UDPGP mRNA, though not to the same extent as seen during normal development. The two UDPGP polypeptides observed in vitro are coordinately regulated. Unaggregated cells, starved and shaken rapidly in suspension, did not show UDPGP mRNA accumulation. However, addition of cAMP to these cells caused UDPGP induction, suggesting that the requirement for cell-cell contact could be bypassed in part by cAMP addition.
mesh_terms: D002449:Cell Aggregation; D002454:Cell Differentiation; D000242:Cyclic AMP / Q000502:physiology; D004023:Dictyostelium / Q000166:cytology / Q000201:enzymology / Q000235:genetics*; D005786:Gene Expression Regulation; D009713:Nucleotidyltransferases / Q000235:genetics*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D000242:Cyclic AMP; D009713:Nucleotidyltransferases; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase