title: The role of abscisic acid in regulating cucumber fruit development and ripening and its transcriptional regulation.
abstract: Cucumber (Cucumis sativus L.), a kind of fruit usually harvested at the immature green stage, belongs to non-climacteric fruit. To investigate the contribution of abscisic acid (ABA) to cucumber fruit development and ripening, variation in ABA level was investigated and a peak in ABA level was found in pulp before fruit get fully ripe. To clarify this point further, exogenous ABA was applied to cucumber fruits at two different development stages. Results showed that ABA application at the turning stage promotes cucumber fruit ripening, while application at the immature green stage had inconspicuous effects. In addition, with the purpose of understanding the transcriptional regulation of ABA, two partial cDNAs of CsNCED1 and CsNCED2 encoding 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthetic pathway; one partial cDNA of CsCYP707A1 for 8'-hydroxylase, a key enzyme in the oxidative catabolism of ABA and two partial cDNAs of CsBG1 and CsBG2 for β-glucosidase (BG) that hydrolyzes ABA glucose ester (ABA-GE) to release active ABA were cloned from cucumber. The DNA and deduced amino acid sequences of these obtained genes respectively showed high similarities to their homologous genes in other plants. Real-time PCR analysis revealed that ABA content may be regulated by its biosynthesis (CsNCEDs), catabolism (CsCYP707A1) and reactivation genes (CsBGs) at the transcriptional level during cucumber fruit development and ripening, in response to ABA application, dehydration and pollination, among which CsNCED1, CsCYP707A1 and CsBG1 were highly expressed in pulp and may play more important roles in regulating ABA metabolism.
authors: College of Agronomy and Biotechnology, China Agricultural University, No.2 West Yuanmingyuan Road, Beijing 100193, China. wangyp_cau@foxmail.com
authors: Yanping
authors: Y
authors: Wang
authors: Ya
authors: Y
authors: Wang
authors: Kai
authors: K
authors: Ji
authors: Shengjie
authors: S
authors: Dai
authors: Ying
authors: Y
authors: Hu
authors: Liang
authors: L
authors: Sun
authors: Qian
authors: Q
authors: Li
authors: Pei
authors: P
authors: Chen
authors: Yufei
authors: Y
authors: Sun
authors: Chaorui
authors: C
authors: Duan
authors: Yan
authors: Y
authors: Wu
authors: Hao
authors: H
authors: Luo
authors: Dian
authors: D
authors: Zhang
authors: Yangdong
authors: Y
authors: Guo
authors: Ping
authors: P
authors: Leng
mesh_terms: D000040:Abscisic Acid / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D028462:Cucumis / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018076:DNA, Complementary; D018744:DNA, Plant; D003681:Dehydration; D005638:Fruit / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008969:Molecular Sequence Data; D010937:Plant Growth Regulators / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D054817:Pollination; D017385:Sequence Homology; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D010937:Plant Growth Regulators; D010940:Plant Proteins; D000040:Abscisic Acid