Genome-wide identification and expression analysis of the aluminum-activated malate transporter gene family in ice plant

doi:10.14088/j.cnki.issn0439-8114.2026.09.033

Abstract

Abstract: To elucidate the phylogenetic and functional characteristics of the aluminum-activated malate transporter (ALMT) gene family in the halophyte ice plant (Mesembryanthemum crystallinum L.), a genome-wide systematic identification of ALMT gene family members in ice plant was conducted, and their expression patterns under salt stress were analyzed. The results showed that a total of 9 McALMT genes were identified in the ice plant genome, unevenly distributed on 5 chromosomes. The isoelectric points of McALMT proteins varied greatly (6.54 to 9.20), all lacked signal peptides, contained 5 to 18 transmembrane domains, and were mainly localized to the plasma membrane. Phylogenetic analysis showed that McALMT and Arabidopsis ALMT (AtALMT) proteins were clustered into 5 clades, and members within the same clade had similar gene structures and conserved motifs. The promoter regions were rich in cis-acting elements such as those responding to salt stress and plant hormones. Expression profile analysis showed that McALMT2 was expressed in roots, stems, and leaves, with higher expression levels in stems and leaves; McALMT1, McALMT8, and McALMT9 exhibited obvious stem tissue preference. Under salt stress, McALMT4 maintained a relatively high expression level at all time points, while McALMT1, McALMT2, and McALMT7 exhibited an obvious temporal dynamic response pattern at 5 days of salt stress.

Key words: ice plant (Mesembryanthemum crystallinum L.), aluminum-activated malate transporter (ALMT), gene family, genome-wide, identification, expression, bioinformatics

CLC Number:

Q943.2

LIU Xiao-han, LIU Xiao-han, YI Rui-ying, SONG Si-han, SU Jia-min, LI Nan, SONG Xiao-ming. Genome-wide identification and expression analysis of the aluminum-activated malate transporter gene family in ice plant[J]. HUBEI AGRICULTURAL SCIENCES, 2026, 65(9): 209-215.

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