NtCPS2基因对烟草腺毛发育及其分泌物合成的影响

Effect of NtCPS2 Gene on Development and Secretion Synthesis of Tobacco Gland Hair

为探讨烟草(Nicotiana tomentosiformis L.)顺-冷杉醇合成基因NtCPS2(Ent⁃copalyl diphosphate synthase 2)与烟草腺毛发育及其分泌物合成的关系,以编辑顺-冷杉醇关键合成基因NtCPS2的8306纯合编辑系(Knock⁃down,KD)和8306野生型品系(Wild⁃type,WT)为材料,比较KD和WT正常生长条件(CK)、外施赤霉素(GA3)及矮壮素后烟株叶片腺毛密度,顺-冷杉醇、西柏三烯二醇和GA3的含量以及相关基因表达量的差异。结果表明,对于CK,与WT相比,KD烟株内源GA3含量显著增加25%,叶片腺毛密度显著增加28%,叶片西柏三烯二醇分泌物含量显著升高25%,西柏烷三烯二醇关键合成基因CYC(Cembratrien⁃ol synthetase)、CYP71D16(Cytochrome P450 hydroxylase)表达量显著升高。外施GA3后,KD和WT中GA3含量平均显著增加50%,叶片腺毛密度平均显著增加50%,叶片西柏三烯二醇含量平均显著升高50%,整体上KD升高幅度大于WT。外施GA3抑制剂矮壮素后,KD和WT内源GA3含量平均显著减少25%,叶片腺毛密度平均显著降低56%,叶片西柏三烯二醇的含量平均显著降低46%,整体上KD下降幅度大于WT。编辑NtCPS2基因后KD烟株GA3含量增加,叶片腺毛密度增加,叶片西柏三烯二醇分泌物含量升高,此结果与外施GA3结果一致,与外施矮壮素结果相反,表明NtCPS2基因通过影响GA3生物合成进而影响烟草腺毛发育及西柏三烯二醇的合成。

To investigate the relationship between tobacco(Nicotiana tomentosiformis L.)cis⁃abisol synthesis gene NtCPS2(ent⁃copalyl diphosphate synthase 2)and tobacco gland hair development and secretion synthesis,the 8306 homozygous editing line(knock⁃down,KD)with the key synthetic gene NtCPS2 of cis⁃abisol edited and 8306 wild⁃type(WT)were used as materials,the glandular hair density,contents of cis⁃abisol,cembranoids and gibberellic acid(GA3)and related gene expression levels of KD and WT were compared under the normal growth conditions(CK),application of GA3 and tetraphyllin.The results showed that for CK,compared with WT,the endogenous GA3 content of KD tobacco plant significantly increased by 25%,the glandular hair density of leaves significantly increased by 28%,the content of cembranoids secretion in leaves significantly increased by 25%,and the expression levels of key synthetic genes of cembranoids CYC(cembratrien⁃ol synthetase)and CYP71D16(cytochrome P450 hydroxylase)significantly increased.After external application of GA3,the content of GA3 in KD and WT increased by an average of 50%,the density of glandular hairs in leaves increased by 50%on average,and the content of cembranoids in leaves increased by 50%on average,and the overall increase in KD was greater than that of WT.After the external application of GA3 inhibitor tetraphyllin,the content of endogenous GA3 of KD and WT decreased by 25%on average,the glandular hair density of leaves significantly reduced by 56%on average,and the content of cembranoids in leaves significantly reduced by 46%on average,and the overall decrease in KD was greater than that of WT.After editing the NtCPS2 gene,the GA3 content of KD tobacco plant increased,the density of leaf glandular hair increased,and the content of cembranoids secretion increased,which was consistent with the result of external application of GA3,and opposite to the result of external application of tetraphyllin,indicating that NtCPS2 gene affects the development of tobacco glandular hair and the synthesis of cembranoids by affecting GA3 biosynthesis.