Chi Yong Hun, Melencion Sarah Mae Boyles, Alinapon Cresilda Vergara, Kim Min Ji, Lee Eun Seon, Paeng Seol Ki, Park Joung Hun, Nawkar Ganesh M, Jung Young Jun, Chae Ho Byoung, Kang Chang Ho, Lee Sang Yeol
Division of Applied Life Science (BK21(+) Program) and PMBBRC, Gyeongsang National University, Jinju, 52828, Republic of Korea.
National Institute of Ecology, 1210 Geumgang-ro, Maseo-myeon, Seocheon-gun 33657, Republic of Korea.
Biochem Biophys Res Commun. 2017 Jul 8;488(4):641-647. doi: 10.1016/j.bbrc.2017.01.047. Epub 2017 Jan 12.
We screened for endoplasmic reticulum (ER) stress-resistant mutants among 25 mutants of the Arabidopsis NTL (NAC with Transmembrane motif 1-Like) family. We identified a novel mutant, SALK_044777, showing strong resistance to ER stress. RT-PCR and genomic DNA sequence analyses identified the mutant as atntl7, which harbors a T-DNA insertion in the fourth exon of AtNTL7. Two other atntl7-mutant alleles, in which T-DNA was inserted in the second exon and third intron of AtNTL7, respectively, showed ER-stress sensitive phenotypes, suggesting that SALK_044777 is a gain-of-function mutant. Arabidopsis plants overexpressing AtNTL7 showed strong ER-stress resistance. Our findings suggest that AtNTL7 fragment is cleaved from the ER membrane under ER stress and translocates into the nucleus to induce downstream ER-stress responsive genes.
我们在拟南芥NTL（具有跨膜基序1样的NAC）家族的25个突变体中筛选了内质网（ER）应激抗性突变体。我们鉴定出一个新的突变体SALK_044777，它对ER应激表现出很强的抗性。RT-PCR和基因组DNA序列分析确定该突变体为atntl7，其在AtNTL7的第四个外显子中存在T-DNA插入。另外两个atntl7突变等位基因，其中T-DNA分别插入AtNTL7的第二个外显子和第三个内含子，表现出ER应激敏感表型，表明SALK_044777是一个功能获得型突变体。过表达AtNTL7的拟南芥植物表现出很强的ER应激抗性。我们的研究结果表明，AtNTL7片段在内质网应激下从内质网膜上裂解下来，并转移到细胞核中以诱导下游内质网应激反应基因。
