作物学报2026，Vol.52Issue(1)：249-261,13.DOI:10.3724/SP.J.1006.2026.54013
烟草NtCEP7基因克隆及其编码小肽在苗期抗旱中的作用分析
Cloning of the NtCEP7 gene in tobacco and functional analysis of its encoded peptide in seedling-stage drought resistance
摘要
Abstract
Although tobacco exhibits strong drought tolerance at maturity,its seedlings are particularly sensitive to water defi-ciency during early developmental stages.Drought stress following field transplantation significantly disrupts plant growth,ultimately reducing yield and compromising leaf quality.C-terminally encoded peptides(CEPs),a class of small peptide hor-mones,are known to play crucial roles in regulating plant responses to abiotic stresses.However,the drought resistance func-tions of CEP family members in tobacco remain largely unexplored.In this study,we cloned the NtCEP7 gene from Nicotiana tabacum cv.K326.The full-length coding sequence(CDS)of NtCEP7 is 261 bp,encoding a protein of 86 amino acids.The predicted propeptide contains a typical secretory signal peptide and a transmembrane domain.Phylogenetic analysis placed NtCEP7 in Group I,and promoter analysis revealed the presence of cis-acting elements responsive to abscisic acid(ABA)and drought stress.Quantitative real-time PCR showed that NtCEP7 expression was significantly upregulated by both drought stress and ABA treatment.To assess its function,drought stress was simulated by withholding water from potted plants.Com-pared to the control group(sprayed with water),plants treated with NtCEP7a maintained a better growth status under drought conditions,which was manifested by milder leaf yellowing and wilting,exhibited increased chlorophyll content,net photo-synthetic rate,dry weight of shoot and proline accumulation,along with decreased electrolyte leakage and malondialdehyde(MDA)levels.Further physiological analysis revealed that NtCEP7a treatment under drought conditions reduced stomatal aperture,increased relative leaf water content,enhanced antioxidant enzyme activities,and lowered levels of superoxide ani-ons and hydrogen peroxide.Collectively,these results indicate that NtCEP7a alleviates drought-induced damage in tobacco by regulating stomatal dynamics,promoting osmoprotectant accumulation,and activating antioxidant defenses,thereby enhancing drought tolerance.关键词
烟草/NtCEP7a小肽/干旱胁迫/气孔开度/抗氧化酶活性Key words
tobacco/NtCEP7a peptide/drought stress/stomatal aperture/antioxidant enzyme activity引用本文复制引用
孔娜,刘涛,刘文婷,陈刚,文利超,邓智超,郭梅,李伟,郭永峰..烟草NtCEP7基因克隆及其编码小肽在苗期抗旱中的作用分析[J].作物学报,2026,52(1):249-261,13.基金项目
本研究由中国烟草总公司山东省公司科技重点项目(KN307),中国农业科学院科技创新工程所级重点项目(ASTIP-TRIC-ZD04)和国家自然科学基金项目(31970204)资助. This study was supported by the Key Science and Technology Project of Shandong Provincial Bureau of China National Tobacco Corporation(KN307),the Agricultural Science and Technology Innovation Program(ASTIP-TRIC-ZD04),and the National Natural Science Foundation of China(31970204). （KN307）
