The Key to Mn Homeostasis in Plants: Regulation of Mn Transporters. (March 2017)

• Record Type: Journal Article
• Authors: Shao, Ji Feng; Yamaji, Naoki; Shen, Ren Fang; Ma, Jian Feng
• Is Part Of: Trends in plant science. Volume 22:Number 3(2017)
• Page Start: 215
• Page End: 224
• Publication Date: 2017-03
• Subjects: Botany -- Periodicals; Botanique -- Périodiques; Botany; Periodicals; 580.5
• DOI: 10.1016/j.tplants.2016.12.005
• Languages: English
• ISSNs: 1360-1385

Abstract

Abstract : Plants only require small amounts of manganese (Mn) for healthy growth, but Mn concentrations in soil solution vary from sub-micromolar to hundreds of micromolar across the growth period. Therefore, plants must deal with large Mn concentration fluctuations, but the molecular mechanisms underlying how plants cope with low and high Mn concentrations are poorly understood. In this Opinion we discuss the role of Mn transporters in the uptake, distribution, and detoxification of Mn in response to changes in Mn concentrations through their regulation at the transcriptional and protein levels, mainly focusing on rice, an Mn-tolerant and −accumulating species. We also propose mechanisms involved in the hyperaccumulation of Mn and future prospects for studying this specific trait. Trends: The concentration of Mn, an essential element for plants, varies in soil solution from submicromolar to hundreds of micromolar across the plant growth period as a function of soil conditions. Recent studies have revealed that some plant species, such as rice, are able to deal with these wide fluctuations of Mn in the environment by differential regulation of transporter expression. OsNramp3 localized at the nodes responds to different Mn concentrations. It functions as a switch in response to changes in Mn levels. Other transporters are also implicated in dealing with changes in Mn levels in different plant species, especially Mn-hyperaccumulators, but their exact roles remain to be examined.