Silencing of the major salt-dependent isoform of pectinesterase in tomato alters fruit softening.
نویسندگان
چکیده
Pectinesterase (PE; E.C. 3.1.1.11) is an enzyme responsible for the demethylation of galacturonyl residues in high-molecular-weight pectin and is believed to play an important role in cell wall metabolism. In this study, Pmeu1, a ubiquitously expressed PE gene, has been characterized by antisense suppression in tomato (Solanum lycopersicum). Transgenic tomato plants showed reduced PE activity levels in both green fruit and leaf tissue to around 65% and 25% of that found in wild-type plants, respectively. Pmeu1 was observed to encode a salt-dependent PE isoform that correlated with PE1 as previously described in fruit tissue. Silencing of Pmeu1 did not result in any detectable phenotype within the leaf tissue despite the gene product representing the major isoform in this tissue. In comparison, silencing in fruit resulted in an enhancement to the rate of softening during ripening. The role of PMEU1 in fruit ripening is discussed.
منابع مشابه
Pectinesterase in normal and abnormal tomato fruit.
Although the pectin content of tomatoes is relatively low in comparison with other fruits (Money & Christian, 1950), the activity of pectinesterase (pectin pectyl-hydrolase, EC 3.1.1.11) is particularly high (Kertesz, 1938). Softening of the fruit takes place relatively rapidly during ripening (Hobson, 1959), and the classical mechanism by which the effect is usually explained assumes the solub...
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عنوان ژورنال:
- Plant physiology
دوره 144 4 شماره
صفحات -
تاریخ انتشار 2007