Open AccessCytokinin biosynthesis genes expressed during nodule organogenesis are directly regulated by the KNOX3 protein in Medicago truncatula
Author(s) -
Mahboobeh Azarakhsh,
Andrey M. Rumyantsev,
Maria A. Lebedeva,
Л. А. Лутова
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0232352
Subject(s) - medicago truncatula , homeobox , biology , gene , transcription factor , cytokinin , microbiology and biotechnology , regulation of gene expression , organogenesis , genetics , symbiosis , auxin , bacteria
Cytokinin is an important regulator of symbiotic nodule development. Recently, KNOTTED1-LIKE HOMEOBOX 3 transcription factor (TF) was shown to regulate symbiotic nodule development possibly via the activation of cytokinin biosynthesis genes. However, the direct interaction between the KNOX3 TF and its target genes has not been investigated up to date. Here, using EMSA analysis and SPR-based assay, we found that MtKNOX3 homeodomain directly binds to the regulatory sequences of the MtLOG1 , MtLOG2 , and MtIPT3 genes involved in nodulation in Medicago truncatula . Moreover, we showed that MtLOG2 and MtIPT3 expression patterns partially overlap with MtKNOX3 expression in developing nodules as it was shown by promoter:GUS analysis. Our data suggest that MtKNOX3 TF may directly activate the MtLOG1 , MtLOG2 , and MtIPT3 genes during nodulation thereby increasing cytokinin biosynthesis in developing nodules.