Genomic analysis of WD40 protein family in the mango reveals a TTG1 protein enhances root growth and abiotic tolerance in Arabidopsis

Lin Tan,Haron Salih,Farrukh Azeem,Nwe Ni Win Htet,Rulin Zhan

doi:10.1038/s41598-021-81969-z

Abstract

WD40 domain-containing proteins constitute one of the most abundant protein families in all higher plants and play vital roles in the regulation of plant growth and developmental processes. To date, WD40 protein members have been identified in several plant species, but no report is available on the WD40 protein family in mango (Mangifera indica L.). In this study, a total of 315 WD40 protein members were identified in mango and further divided into 11 subgroups according to the phylogenetic tree. Here, we reported mango TRANSPARENT TESTA GLABRA 1 (MiTTG1) protein as a novel factor that functions in the regulation of Arabidopsis root growth and development. Bimolecular fluorescence complementation (BiFC) assay in tobacco leaves revealed that MiTTG1 protein physically interacts with MiMYB0, MiTT8 and MibHLH1, implying the formation of a new ternary regulatory complex (MYB-bHLH-WD40) in mango. Furthermore, the MiTTG1 transgenic lines were more adapted to abiotic stresses (mannitol, salt and drought stress) in terms of promoted root hairs and root lengths. Together, our findings indicated that MiTTG1 functions as a novel factor to modulate protein–protein interactions and enhance the plants abilities to adjust different abiotic stress responses.

Highlights

WD40 domain-containing proteins constitute one of the most abundant protein families in all higher plants and play vital roles in the regulation of plant growth and developmental processes
Several WD40 proteins that are orthologs to the Arabidopsis TTG1 gene have been identified in some plant species, such as cotton (Gossypium hirsutum), Prunus persica, Punica granatum and maize (Zea mays)[26,27,28,29]
To elucidate the function of the MiTTG1 in root development, we systematically investigated the root phenotypes in young Arabidopsis transgenic lines (MiTTG1 was introduced into the wild-type) and wild-type

Summary

Introduction

WD40 domain-containing proteins constitute one of the most abundant protein families in all higher plants and play vital roles in the regulation of plant growth and developmental processes. We reported mango TRANSPARENT TESTA GLABRA 1 (MiTTG1) protein as a novel factor that functions in the regulation of Arabidopsis root growth and development. WD40-REPEAT 5a plays an important role in drought tolerance through the regulation of nitric oxide a ccumulation[12] Another WD40 protein (XIW1) is directly involved in the association of the stability ABI5 and ABA responses in Arabidopsis[13]. We identified 315 WD40 protein members in mango at a genomic analysis level, including their domain numbers, evolutionary relationship, gene location and predicted molecular functions. We reported the molecular cloning of cDNA encoding a mango WD40 protein, MiTTG1 (Mi01g20920), an ortholog of the Arabidopsis AT5G24520 (TTG1) which promotes root growth and enhances osmotic, salt and drought stress tolerance in Arabidopsis. This work will provide a solid platform to better understand the functional roles of MiTTG1 gene and will help further investigation on the biological function and molecular mechanisms of these proteins family in mango

Methods

Results

Conclusion