Analysis of LE-ACS3, a 1-aminocyclopropane-1-carboxylic acid synthase gene expressed during flooding in the roots of tomato plants.
The plant hormone ethylene is produced in response to a variety of environmental stresses. Previous work has shown that flooding or anaerobic stress in the roots of tomato plants caused an increase in the production of the ethylene precursor 1-aminocyclopropane-1-carboxylate (ACC) in the roots, due to flooding-induced activity of ACC synthase (EC 4.4.1.14). RNA was extracted from roots and leaves of tomato plants flooded over a period of 48 h. Blot analysis of these RNAs hybridized with probes for four different ACC synthases revealed that the ACC synthase gene LE-ACS3 is rapidly induced in roots. LE-ACS2 is also induced, but at later times. The genomic clone for LE-ACS3 was isolated and sequenced. At all time points, the probe from the LE-ACS3 coding region hybridized to two bands in the RNA blots. Hybridization using the first and third introns of LE-ACS3 separately as probes indicate that flooding may inhibit processing of the LE-ACS3 transcript. Sequence homology analysis identified three putative cis-acting response elements in the promoter region, corresponding to the anaerobic response element from the maize adh1 promoter, the root-specific expression element from the cauliflower mosaic virus 35S promoter and a recognition element for chloroplast DNA binding factor I from the maize chloroplast ATP synthase promoter.
Olson
D C
DC
Mann Laboratory, Department of Vegetable Crops, University of California, Davis 95616, USA.
Oetiker
J H
JH
Yang
S F
SF
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017343:Genes, Plant; D007438:Introns; D008190:Lyases / Q000235:genetics*; D018551:Solanum lycopersicum / Q000235:genetics*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis
D012333:RNA, Messenger; D008190:Lyases; C021773:1-aminocyclopropanecarboxylate synthase