Suchergebnisse

AbstractBackgroundFlavonols play important roles in antioxidation and anticancer activities, longevity, and cardiovascular protection.Flavonol synthase(FLS) is a key enzyme for flavonol synthesis.ResultPhenotypic, transcriptional and metabolic data were analyzed, which showed that there was a close relationship between salt stress and flavonoids, and flavonols were significantly upregulated under salt stress. Nine, seven, four, and fourFLSgenes were identified inGossypium hirsutum,Gossypium barbadense,Gossypium arboreum, andGossypium raimondii,respectively. The results of subcellular localization showed that FLS existed in the nucleus and cytoplasmic. Through phylogenetic analysis, 24FLSgenes were divided into three subfamilies. The results of the RNA sequencing showed that the expression ofGhFLSgenes was mainly induced by salt, drought, low temperature, and heat stress.GhFLSpromoter mainly comprised plant hormone response elements and abiotic stress elements, indicating that theGhFLSgene may play a key role in abiotic stress response. The proline contents of pYL156:GhFLS1 was reduced significantly compared to pYL156 under salt stress, thereby reducing the resistance of cotton to salt stress.ConclusionThis study will lay a foundation for further study on the antioxidant regulation mechanism of theFLSgene under abiotic stress.

AbstractCytokinin oxidase/dehydrogenase (CKX) is a key regulatory enzyme for the irreversible degradation of the plant hormone cytokinin (CK), which is important in growth and development and response to abiotic stresses in cotton. In this study, 27, 28, 14 and 14 CKXs were screened by FAD structural domain and cytokinin binding structural domain in Gossypium hirsutum, Gossypium barbadense, Gossypium arboreum and Gossypium raimondii, respectively. Their phylogenetic relationships and expression patterns were analyzed, and most GhCKXs were found to be tissue-specific and responsive to various abiotic stresses such as cold, heat, salt and PEG. GhCKX6b-Dt was selected for gene silencing in evolutionary branch II for salt stress, because its expression increased after salt stress in cotton plants. An increase in PRO and MDA content and a decrease in SOD activity due to this gene were found after inducing salt stress, contributing to oxidative damage and decreased salt tolerance. In this study, CKXs were analyzed to reveal the possible role of GhCKXs against abiotic stresses in cotton, which provides a basis for further understanding of the biological functions of CK in plants such as growth and development and stress resistance.