细胞分裂素转运蛋白在细胞分裂素平衡和信号分布中的作用

Role of Cytokinin Transporter Proteins in Cytokinin Homeostasis and Signal Distribution

摘要: 细胞分裂素(CK)是一类可移动的腺嘌呤衍生物，它们作为化学信号调节与植物发育和胁迫反应有关的各种生物过程。它们的合成、稳态和信号感知会引起复杂的细胞内交通、细胞间移动以及短距离和长距离转运。近二十年来，膜转运蛋白的亚群已被识别并参与CK以及相关腺苷酸的转运。本文旨在回顾参与细胞分裂素运输和易位的转运蛋白探索的主要进展，讨论它们在细胞分裂素介导的旁分泌和远距离通讯中的功能意义，并强调一些知识空白和开放性问题，以全面理解膜转运蛋白在控制细胞分裂素物种时空分布中的分子机制。

Abstract: Cytokinins (CKs) are a group of mobile adenine derivatives that act as chemical signals regulating a variety of biological processes implicated in plant development and stress responses. Their synthesis, homeostasis, and signaling perception evoke complicated intracellular traffic, intercellular movement, and in short- and long-distance translocation. Over nearly two decades, subsets of membrane transporters have been recognized and implicated in the transport of CKs as well as the related adenylates. In this review, we aim to recapitulate the key progresses in exploration of the transporter proteins involved in cytokinin traffic and translocation, discuss their functional implications in the cytokinin-mediated paracrine and long-distance communication, and highlight some knowledge gaps and open issues toward comprehensively understanding the molecular mechanism of membrane transporters in controlling spatiotemporal distribution of cytokinin species.