毛竹中NYE基因的分离及功能分析

Isolation and Function Analysis of NYE Genes in Moso [Phyllostachys edulis (Carr.) Lehaie]

AtNYE1是拟南芥叶片衰老过程中叶绿素降解的重要调控基因,本文用AtNYE1为诱饵基因,通过NCBI tblastn在毛竹的cDNA文库中找到3个与其相似性较高的cDNA全长序列,分别命名为PeNYE1、PeNYE2和PeNYE3。为了验证其是否具有AtNYE1相似的功能,分别将它们的编码区构建到带有花椰菜花叶病毒35S强启动子的植物表达载体上,并通过冻融法将这3个表达载体导入GV3101农杆菌。通过农杆菌介导法,将这3个基因分别在烟草叶片中瞬时表达及在拟南芥植株中稳定表达,结果显示,瞬时过表达和组成型过表达PeNYE1均导致了叶片的黄化,而瞬时或组成型过表达PeNYE2或PeNYE3均未观察到黄化表型。这些结果表明PeNYE1是毛竹中叶绿素降解的重要调控基因。

AtNYE1 is an important chlorophyll degradation regulatory gene during leaf senescence of Arabidopsis thaliana. With AtNYE1 as a bait gene, three sequences which have high similarity with AtNYE1 were found in the moso （Phyllostachys edulis） EST database through NCBI tblastn, and were named PeNYE1, PeNYE2 and PeNYE3 respectively. To verify whether those genes have the similar function of AtNYE1, the coding regions of PeNYE1, PeNYE2 and PeNYE3 were constructed to the plant expression vector with CaMV 35S promoter. And the resulting constructs were introduced into Agrobacterium tumefaciens GV3101 through the freeze-thaw method. By Agrobacterium-mediated method, the three genes were transiently expressed in tobacco leaves and constitutively expressed in Arabidopsis plants, respectively. The results showed that both transient-expression and constitutive-expression of PeNYE1 could result in the leaf yellowing phenotype. But transientor constitu- tive-overexpression of PeNYE2 or PeNYE3 couldn＇t induce the leaf de-greening phenotype. The results collectively indicate that PeNYE1 is an important regulator gene of chlorophyll degradation in moso.