AUTHOR=Tan Lin , Waqas Muhammad , Rehman Abdul , Rashid Muhammad Abdul Rehman , Fiaz Sajid , Manzoor Hamid , Azeem Farrukh 

TITLE=Computational analysis and expression profiling of potassium transport-related gene families in mango (Mangifera indica) indicate their role in stress response and fruit development

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1102201

DOI=10.3389/fpls.2022.1102201

ISSN=1664-462X

ABSTRACT=<p>Mango (<italic>Mangifera indica</italic>) fruit is known for its taste, health benefits, and drought tolerance. Potassium (K<sup>+</sup>) is one of the most abundant ions in a plant cell. It is important for various biological functions related to plant growth, development, and flowering/fruiting. It significantly contributes to fruit yield, quality, and drought tolerance in plants. However, molecular mechanisms comprising K<sup>+</sup> transport in mango are least known. In the present study, 37 members of K<sup>+</sup> transport-related genes (PTGs) were identified in mango, which include 22 K<sup>+</sup> transporters (16 HAKs, 1 HKT, and 6 KEAs) and 15 K<sup>+</sup> channels (6 TPKs and 8 Shakers). All PTGs were predicted to be expressed at the plasma membrane and possess characteristic motifs and domains. Phylogenetic analysis identified a strong kinship of PTGs among <italic>Oryza sativa</italic>, <italic>Arabidopsis thaliana</italic>, <italic>Cicer arietinum</italic>, <italic>Malus domestica</italic>, and <italic>M. indica</italic>. The promoter analysis identified 60 types of <italic>cis</italic>-elements related to various biological processes. RNA-seq-based expression profiling identified that <italic>MiTPK1.2</italic>, <italic>MiHAK1</italic>, <italic>MiHAK2.1</italic>, <italic>HAK6.1</italic>, and <italic>MiAKT1.1</italic> were most upregulated in roots and that <italic>MiKEA2</italic>, <italic>MiAKT2</italic>, and <italic>MiAKT1</italic> were upregulated in leaves. Moreover, <italic>MiAKT6</italic>, <italic>MiHAK1.1</italic>, <italic>MiKAT2</italic>, <italic>MiKAT2.1</italic>, <italic>MiHKT1</italic>, <italic>MiTPK1.1</italic>, <italic>MiHAK7</italic>, and <italic>MiHAK12</italic> were highly expressed during the five growth stages of mango fruit. The current study is the first comprehensive report on K<sup>+</sup> transport system in tropical fruits. Therefore, it will provide the foundation knowledge for the functional characterization of K<sup>+</sup> genes in mango and related plants.</p>