烟草磺肽素(PSK)基因家族鉴定及抗旱功能分析

Analysis of Sulfopeptin(PSK)Gene Family and Drought Resistance in Tobacco

为研究植物磺肽素(PSK)小肽在烟草抗旱中的作用,采用生物信息学方法,在普通烟草基因组中鉴定了9个NtPSK基因,分析了其蛋白结构;并对干旱处理下的烟苗和烟株喷施PSK,观察其对烟苗和烟株生长发育及抗旱相关生理指标的影响。结果表明:9个NtPSK基因编码的蛋白C端高度保守,均具有小肽成熟体结构域(YIYTQ)。1μmol/L PSK小肽处理的烟苗在干旱胁迫下能促进主根的伸长,叶片SOD活性显著提高,活性氧含量降低;1μmol/L PSK小肽处理的烟株抗旱效果明显,其叶片相对含水量、脯氨酸含量均升高,丙二醛含量、过氧化氢含量均显著下降。本研究表明PSK小肽能够缓解干旱对烟草生长发育的不良影响,提高烟草的抗旱能力。

To investigate the role of the plant sulfopeptin(PSK)small peptide in tobacco drought resistance,we utilized bioinformatic methods to identify 9 NtPSK genes within the tobacco genome and analyze their corresponding protein structures.Subsequently,PSK peptide was administered to tobacco plants under drought conditions,to evaluate its effects on the development of tobacco seedlings and plants.Our findings revealed a highly conserved YIYTQ motif in the C-terminal region of the 9 prePSK proteins.Notably,treatment of tobacco seedlings with 1μmol/L PSK peptide during drought stress promoted taproot elongation,substantially enhanced leaf SOD activity,and reduced reactive oxygen species levels.Similarly,application of 1μmol/L PSK peptide to tobacco plants yielded significant improvements in drought resistance,evidenced by increased relative water content and proline levels,alongside notable reductions in malondialdehyde and hydrogen peroxide content.These findings collectively suggest that PSK peptide holds promise in alleviating the deleterious effects of drought on tobacco growth and development,thereby enhancing its resilience to drought stress.