AtNPF6.4運輸功能以及在阿拉伯芥受丁香假單孢菌感染時防禦反應之角色

Analysis of AtNPF6.4 transport activity and its role in Arabidopsis response to Pseudomonas syringae

任家佑(Chia-Yu Jen)

指導教授 ： 蔡皇龍

共同指導教授 ： 王雅筠(Ya-Yun Wang)

國立臺灣大學/生命科學院/分子與細胞生物學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202103588

摘要

我們研究室先前的研究發現屬於硝酸鹽/短胜肽轉運蛋白家族(Nitrate transporter 1/Peptide transporters family, NPF)的轉運蛋白NPF6.4參與植物遭受丁香假單孢菌(Pseudomonas syringae)亞種DC3000感染時的PTI (PAMP Triggered Immunity)；然而關於如何參與的詳細機轉目前研究尚淺。本研究探討NPF6.4在PTI中的角色，首先測定NPF6.4的受質。在以非洲爪蟾(Xenopus laevis)的卵母細胞作為轉運蛋白表現平台的測試實驗中，我們確立硝酸鹽為NPF6.4的受質。而後進一步以模式植物阿拉伯芥(Arabidopsis thaliana)的葉部做為測試對象，測量野生種(Columbia-0, Col-0)、npf6.4突變株與fls2突變株在受到細菌感染時的硝酸鹽濃度變化。由目前實驗的結果得知相較於Col-0野生種以及fls2突變株，npf6.4突變株在受到感染時葉部的硝酸鹽濃度沒有明顯變化，因此推測儘管NPF6.4的確作為硝酸鹽轉運蛋白，NPF6.4可能不會影響阿拉伯芥在遭遇丁香假單孢菌DC3000時，葉部的硝酸鹽濃度變化。對於硝酸鹽轉運蛋白NPF6.4在PTI中的角色，還需要進一步的研究。

關鍵字

NPF6.4 ； 丁香假單孢菌 ； 硝酸鹽

並列摘要

Previous work in the lab have shown that NPF6.4, a member of NPF (Nitrate transporter 1/Peptide transporters family), participates PTI (PAMP-triggered immunity) response in Arabidopsis thaliana upon Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) infection. Here we focused on the functional analysis of NPF6.4 and the role of NPF6.4 in PTI response In the uptake assay by the Xenopus oocytes expression system, we confirmed that NPF6.4 mediates the nitrate transport. We then examined the foliar nitrate concentration in wild type (Columbia-0), npf6.4 mutants and fls2 mutant line of Arabidopsis thaliana upon pathogen infection. The results showed that there are no significant changes in nitrate concentration between wild type (Columbia-0), npf6.4 mutants and fls2 mutant line. Therefore, despite being a nitrate transporter, NPF6.4 may not affects the foliar nitrate changes when plants encounter Pst DC3000. The role of NPF6.4 in PTI response requires further investigation.

並列關鍵字

NPF6.4 ； P. syringae ； nitrate

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