Characterization of Pp-CTR1 gene expression during fruit development and ripening in peach (Prunus persica).

摘要

Ethylene is an important factor for the development and maturation of fruits. The cDNA full sequence of Pp-CTR1 involving in ethylene signalling was cloned from Prunus persica 'Rui pan 4' and its expression in the fruits and seeds were analyzed. The main results were as follows. The cDNA of Pp-CTR1 (FJ982370) with 3124 bp full-length and 2532 bp ORF encoded a polypeptide of 843 amino acid. Pp-CTR1 had the conserved serine/threonine kinase domain, including ATP-binding site, and serine/threonine kinase catalytic site. Pp-CTR1 expression patterns in fruits and seeds were significantly different with developmental stages. During the first exponential growth phase of peach fruit (S1), Pp-CTR1 expression in the young fruits enhanced rapidly. At the slower growth stage of peach fruit (S2), opposite to its expression with quick decrease in young fruits, the expression of Pp-CTR1 in seeds increasedobviously. In the third stage with fruits growing rapidlyagain (S3), with the Pp-CTR1 expression in fruitsraising again, its expression in seeds reduced. These results suggested that Pp-CTR1 probably played an important role in regulating peach fruit and seed development. During the ripening and softening of peach fruit, Pp-CTR1 expression in fruit kept a lower level witha slight change. An opposite tendency was observed between Pp-CTR1 expression pattern and ethyleneevolution. However, the expression level of Pp-CTR1 in seeds was higher than that of in fruit, and showed significant increase at the late stage of storage.