Abstract NCED1 (9-cis-epoxy carotenoid dioxygenase) plays important roles in controlling ABA levels and drought stress tolerance. The relationships between sequence polymorphisms of the TaNCED1 gene and drought resistance in wheat were analysed. Four allelic variations of the TaNCED1-5B generated to drought resistance were identified. Four groups of KASP (kompetitive allele-specific PCR) markers were developed based on the four alleles and were verified in a natural population of 311 wheat cultivars. The distribution of the four alleles of TaNCED1-5B in the natural population was clarified. Among the allelic variations, 84.62% of the wheat varieties with TT/-/C/-,TT/C/C/-,TT/-/C/G or TT/C/C/G haplotypes were dryland cultivars. The common feature of the above four haplotypes is that they all contain the TT (98) and C (343) alleles at the TaNCED1-5B-TT/CG (98) and TaNCED1-5B-C/T (343) loci, which indicated that these two locis had highly positive correlation with drought resistance in wheat. NCED 9cisepoxy cisepoxy 9 cis epoxy dioxygenase tolerance TaNCED analysed TaNCED15B TaNCEDB 5B B identified kompetitive allelespecific allele specific PCR 31 cultivars clarified 8462 84 62 84.62 TT//C/,TT/C/C/,TT//C/G TTCTTCCTTCG TT/ /C/ ,TT/C/C/ ,TT/ /C/G G TTCCG 98 (98 343 (343 TaNCED15BTT/CG TaNCED15BTTCG TaNCEDBTTCG TT/CG CG TaNCED15BC/T TaNCED15BCT TaNCEDBCT C/T T loci 3 846 8 6 84.6 /C TTCC ,TT/C/C ,TT (9 34 (34 TaNCED15BTT BTT BTTCG TTCG TaNCED15BC BC BCT CT 84. ( (3 TaNCEDBTT TaNCEDBC

Abstract The destruction of the pulmonary epithelial barrier in acute respiratory distress syndrome is caused by the damage of the alveolar epithelial cells. Oroxin A is an effective flavonoid component derived from the medicinal plant Oroxylum indicum (L.) Kurz. In this study, the oleic acid (OA)-induced A549 cell injury model was established in vitro to explore the protective mechanism of Oroxin A. The experiment was divided into the following groups: control, OA and OA + Oroxin A group. The OA-induced A549 cell injury was dose (time)-dependent and was detected by the CCK-8 assay. The protein and mRNA expression levels associated with pyroptosis are detected by Western blotting and RT-qPCR. After Oroxin A treatment, the levels of IL-1β, IL-18 and LDH released were significantly lower than the OA group. In terms of pyroptosis, Oroxin A can inhibit the expression of pyroptosis-related protein and mRNA. Significantly, the surfactant protein C (SPC) level in the OA + Oroxin A group was significantly higher than that in the OA group. The treatment with Oroxin A alleviates the OA-induced injury in the A549 cells, and its mechanism may be related to the inhibition of A549 cells pyroptosis and prevention of the degradation of the SPC.