Ethylene receptor expression is regulated during fruit ripening, flower senescence and abscission.
Using the Arabidopsis ethylene receptor ETR1 as a probe, we have isolated a tomato homologue (tETR) from a ripening cDNA library. The predicted amino acid sequence is 70% identical to ETR1 and homologous to a variety of bacterial two component response regulators over the histidine kinase domain. Sequencing of four separate cDNAs indicates that tETR lacks the carboxyl terminal response domain and is identical to that encoded by the tomato Never ripe gene. Ribonuclease protection showed tETR mRNA was undetectable in unripe fruit or pre-senescent flowers, increased in abundance during the early stages of ripening, flower senescence, and in abscission zones, and was greatly reduced in fruit of ripening mutants deficient in ethylene synthesis or response. These results suggest that changes in ethylene sensitivity are mediated by modulation of receptor levels during development.
BBSRC Research Group in Plant Gene Regulation, Department of Physiology and Environmental Science, University of Nottingham, Loughborough, UK.
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Payton
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Fray
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Brown
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Grierson
D000595:Amino Acid Sequence; D001483:Base Sequence; D005030:Ethylenes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018551:Solanum lycopersicum / Q000235:genetics / Q000254:growth & development*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000096:biosynthesis* / Q000235:genetics; D018520:Plant Shoots / Q000254:growth & development*; D012333:RNA, Messenger / Q000096:biosynthesis; D018749:RNA, Plant / Q000096:biosynthesis; D011956:Receptors, Cell Surface / Q000096:biosynthesis* / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
D005030:Ethylenes; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D011956:Receptors, Cell Surface; C083750:ethylene receptors, plant; C036216:ethylene