Identification of cis-elements for ethylene and circadian regulation of the Solanum melongena gene encoding cysteine proteinase.
We have previously shown that the expression of SmCP which encodes Solanum melongena cysteine proteinase is ethylene-inducible and is under circadian control. To understand the regulation of SmCP, a 1.34-kb SmCP 5'-flanking region and its deletion derivatives were analyzed for cis-elements using GUS and luc fusions and by in vitro binding assays. Analysis of transgenic tobacco transformed with SmCP promoter-GUS constructs confirmed that the promoter region -415/+54 containing Ethylene Responsive Element ERE(-355/-348) conferred threefold ethylene-induction of GUS expression, while -827/+54 which also contains ERE(-683/-676), produced fivefold induction. Using gel mobility shift assays, we demonstrated that each ERE binds nuclear proteins from both ethephon-treated and untreated 5-week-old seedlings, suggesting that different transcriptions factors bind each ERE under varying physiological conditions. Binding was also observed in extracts from senescent, but not young, fruits. The variation in binding at the EREs in fruits and seedlings imply that organ-specific factors may participate in binding. Analysis of transgenic tobacco expressing various SmCP promoter-luc constructs containing wild-type or mutant Evening Elements (EEs) confirmed that both conserved EEs at -795/-787 and -785/-777 are important in circadian control. We confirmed the binding of total nuclear proteins to EEs in gel mobility shift assays and in DNase I footprinting. Our results suggest that multiple proteins bind the EEs which are conserved in plants other than Arabidopsis and that functional EEs and EREs are present in the 5'-flanking region of a gene encoding cysteine proteinase.
Department of Botany, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
Reetika
R
Rawat
Zeng-Fu
ZF
Xu
Kwok-Ming
KM
Yao
Mee-Len
ML
Chye
D024506:5' Flanking Region / Q000235:genetics; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002940:Circadian Rhythm / Q000502:physiology*; D003546:Cysteine Endopeptidases / Q000235:genetics*; D018983:DNA Footprinting / Q000379:methods; D003850:Deoxyribonuclease I / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D005030:Ethylenes / Q000494:pharmacology*; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000494:pharmacology; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020218:Response Elements / Q000235:genetics*; D032323:Solanum melongena / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D014026:Nicotiana / Q000235:genetics
D005030:Ethylenes; D009687:Nuclear Proteins; D009943:Organophosphorus Compounds; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; C036216:ethylene; D008156:Luciferases; D003850:Deoxyribonuclease I; D005966:Glucuronidase; D003546:Cysteine Endopeptidases; C005073:ethephon