小柯机器人

近日，中国科学技术大学孙林峰等研究人员合作揭示拟南芥PIN1介导生长素识别和流出的结构基础。2022年8月2日，《自然》杂志在线发表了这项成果。

研究人员报告了PIN-FORMED（PIN）家族的主要成员，拟南芥的PIN1（AtPIN1）的三种内向构象结构。(i) apo状态，(ii) 天然生长素、吲哚-3-乙酸（IAA）结合状态，以及(iii) 与极性生长素运输（PAT）抑制剂N-1-naphthylphthalamic acid（NPA）的复合状态。AtPIN1的跨膜结构域有一个保守的NhaA-fold。在底物结合结构中，IAA通过疏水堆积和氢键协调。抑制剂NPA以更高的亲和力与IAA竞争细胞内口袋的同一位置。这些发现促进了人们对PIN的底物识别和运输机制的理解，并为未来对生长素的定向移动研究建立了一个框架，这是植物发育的最关键过程之一。

据悉，PAT是植物特有的，它协调着植物的生长和发育。在质膜上具有显著不对称定位的PIN生长素运输体驱动PAT，然而，它们的结构和运输机制在很大程度上仍然是未知的。

附：英文原文

Title: Structural insights into auxin recognition and efflux by Arabidopsis PIN1

Author: Yang, Zhisen, Xia, Jing, Hong, Jingjing, Zhang, Chenxi, Wei, Hong, Ying, Wei, Sun, Chunqiao, Sun, Lianghanxiao, Mao, Yanbo, Gao, Yongxiang, Tan, Shutang, Friml, Ji, Li, Dianfan, Liu, Xin, Sun, Linfeng

Issue&Volume: 2022-08-02

Abstract: Polar auxin transport (PAT) is unique to plants and coordinates their growth and development1,2. The PIN-FORMED (PIN) auxin transporters with remarkable asymmetrical localizations at the plasma membrane drive PAT3,4, however, their structures and transport mechanisms remain largely unknown. Here, we report three inward-facing conformation structures of the major member of the PIN family, PIN1 in Arabidopsis thaliana (AtPIN1): (i) in the apo state, (ii) in the natural auxin, indole-3-acetic acid (IAA)-bound state, and (iii) in complex with the PAT inhibitor N-1-naphthylphthalamic acid (NPA). The transmembrane domain of AtPIN1 shares a conserved NhaA-fold5. In the substrate-bound structure, IAA is coordinated through both hydrophobic stacking and hydrogen bonding. The inhibitor NPA competes with IAA for the same site of the intracellular pocket with a much higher affinity. These findings facilitate our understanding of the substrate recognition and transport mechanisms of PINs, and set up a framework for future research on the directional auxin movement, one of the most crucial processes underlying plant development.

DOI: 10.1038/s41586-022-05143-9

Source: https://www.nature.com/articles/s41586-022-05143-9

Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html