RESUMEN
Carotenoids are powerful antioxidants that mediate transfer of electrons, directly affect abiotic stress responses in plants through regulating activity of antioxidant enzymes. ζ-Carotene desaturase (ZDS) is a key enzyme in carotenoid biosynthesis pathway, which can catalyze ζ-carotene to form lycopene to regulate carotenoid biosynthesis and accumulation. However, the mechanism of its regulation of saline-alkali stress remains unclear. In this research, based on transcriptomic analysis of Malus halliana with a apple rootstock, we screened out ZDS gene (LOC103451012), with significantly high expression by saline-alkali stress, whose expression in the leaves was 10.8-fold than that of the control (0 h) under 48 h of stress. Subsequently, the MhZDS gene was isolated from M. halliana, and transgenic Arabidopsis thaliana, tobacco, and apple calli were successfully obtained through agrobacterium-mediated genetic transformation. We found that overexpression of MhZDS enhanced the tolerance of A. thaliana, tobacco and apple calli under saline-alkali stress and caused a variety of physiological and biochemical changes: compared with wild-type, transgenic plants grew better under saline stress and MhZDS-OE lines showed higher chlorophyll content, POD, SOD, CAT activities and proline content, lower electrical conductivity and MDA content. These results indicate that MhZDS plays an important role in plant resistance to saline-alkali stress, providing excellent resistance genes for the regulatory network of salinity stress response in apples and provide a theoretical basis for the breeding of apple varieties with strong saline-alkali resistance. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01333-5.
RESUMEN
BACKGROUND: The relation between tea consumption and age-related changes in high-density lipoprotein cholesterol (HDL-C) concentrations remains unclear, and longitudinal human data are limited. The aim of current study was to examine the relation between tea intake and longitudinal change in HDL-C concentrations. METHODS AND RESULTS: Baseline (2006) tea consumption was assessed via a questionnaire, and plasma HDL-C concentrations were measured in 2006, 2008, 2010, and 2012 among 80 182 individuals (49±12 years of age) who did not have cardiovascular diseases or cancer, or did not use cholesterol-lowering agents both at baseline (2006) and during the follow-up period (2006-2012). The associations between baseline tea consumption and rate of change in HDL-C concentrations were examined using generalized estimating equation models. Tea consumption was inversely associated with a decreased rate of HDL-C concentrations (P-trend <0.0001) in the fully adjusted model. The adjusted mean difference in the HDL-C decreased rate was 0.010 (95% confidence interval, 0.008, 0.012) mmol/L per year for tea consumers versus nonconsumers (never or less than once/month group). Interactions between tea consumption and age, sex, lifestyle scores, and metabolic syndrome (all P-interaction <0.0001) were identified. The associations between greater tea consumption and slower decrease in HDL-C concentrations were more pronounced in men, individuals aged 60 or older, individuals with a lower lifestyle score, and individuals with metabolic syndrome (all P-trend <0.0001). CONCLUSIONS: Tea consumption was associated with slower age-related decreases in HDL-C concentrations during 6 years of follow-up. CLINICAL TRIAL REGISTRATION: URL: www.chictr.org. Unique identifier: ChiCTR-TNRC-11001489.