Research Article

Ion transporters and their molecular regulation mechanism in plants

Walid Saibi and Faiçal Brini*

Published: 05/26/2021 | Volume 5 - Issue 2 | Pages: 028-043

Abstract

With the global population predicted to grow by at least 25% by 2050, the need for sustainable production of nutritious foods is important for human and environmental health. Recent progress demonstrate that membrane transporters can be used to improve yields of staple crops, increase nutrient content and resistance to key stresses, including salinity, which in turn could expand available arable land. Exposure to salt stress affects plant water relations and creates ionic stress in the form of the cellular accumulation of Na+ and Cl- ions. However, salt stress also impacts heavily on the homeostasis of other ions such as Ca2+, K+, and NO3- and therefore requires insights into how transport and compartmentation of these nutrients are altered during salinity stress. Since Na+ interferes with K+ homeostasis, maintaining a balanced cytosolic Na+/K+ ratio has become a key salinity tolerance mechanism. Achieving this homeostatic balance requires the activity of Na+ and K+ transporters and/or channels. The aim of this review is to seek answers to this question by examining the role of major ions transporters and channels in ions uptake, translocation and intracellular homeostasis in plants.

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