Genome-wide analysis of HAK/KUP/KT potassium transporter genes in banana (Musa acuminata L.) and their tissue-specific expression profiles under potassium stress

Abstract

Potassium is one of the most essential inorganic cations for plant growth and development. The high a nity K + (HAK)/K + uptake (KUP)/K + transporter (KT) family plays essential roles in the regulation of cellular K + levels and the maintenance of osmotic balance. However, the roles of these genes in the responses of bananas to low-potassium stress are unclear. In this study, 24 HAK/KUP/KT (MaHAK) genes were identi ed from banana genomic data. These genes were further classi ed into four groups based on phylogenetic analysis, gene structure and conserved domain analysis. Segmental duplication events played an important role in the expansion of the MaHAK gene family. Transcriptome analysis revealed the expression patterns of MaHAKs in various tissues under different K + conditions. MaHAK14b was upregulated under both short-and long-term K + -de cient conditions, suggesting that it plays crucial roles in K + uptake at low K + concentrations. Furthermore, MaHAK14b mediated K + uptake when it was heterologously expressed in the yeast mutant R5421 on low K + medium. Collectively, these ndings provide a foundation for further functional analysis of MaHAK genes, which may be used to improve stress resistance in bananas.

MaHAK5, a Potassium Transporter of Banana, Enhanced Potassium Uptake in Transgenic Arabidopsis under Low Potassium Conditions

“…Currently, the family has been studied in various plants regarding K + acquisition, salt tolerance, and K + translocation [11,27]. Recently, 24 KUP/HAK/KT genes were identified in the Musa A genome [28]. However, their physiological roles remained uncharacterized in banana.…”