Genome-wide analyses of the mung bean NAC gene family reveals orthologs, co-expression networking and expression profiling under abiotic and biotic stresses

Abstract

Background Mung bean is a short-duration and essential food crop owing to its cash prominence in Asia. Mung bean seeds are rich in protein, fiber, antioxidants, and phytonutrients. The NAC transcription factors (TFs) family is a large plant-specific family, participating in tissue development regulation and abiotic and biotic stresses. Results In this study, we perform genome-wide comparisons of VrNAC with their homologs from Arabidopsis. We identified 81 NAC transcription factors (TFs) in mung bean genome and named as per their chromosome location. A phylogenetic analysis revealed that VrNACs are broadly distributed in nine groups. Moreover, we identified 20 conserved motifs across the VrNACs highlighting their roles in different biological process. Based on the gene structure of the putative VrNAC and segmental duplication events might be playing a vital role in the expansion of mung bean genome. A comparative phylogenetic analysis of mung bean NAC together with homologs from Arabidopsis allowed us to classify NAC genes into 13 groups, each containing several orthologs and paralogs. Gene ontology (GO) analysis categorized the VrNACs into biological process, cellular components and molecular functions, explaining the functions in different plant physiology processes. A gene co-expression network analysis identified 173 genes involved in the transcriptional network of putative VrNAC genes. We also investigated how miRNAs potentially target VrNACs and shape their interactions with proteins. VrNAC1.4 (Vradi01g03390.1) was targeted by the Vra-miR165 family, including 9 miRNAs. Vra-miR165 contributes to leaf development and drought tolerance. We also performed qRT-PCR on 22 randomly selected VrNAC genes to assess their expression patterns in the NM-98 genotype, widely known for being tolerant to drought and bacterial leaf spot disease. Conclusions This genome-wide investigation of VrNACs provides a unique resource for further detailed investigations aimed at predicting orthologs functions and what role the play under abiotic and biotic stress, with the ultimate aim to improve mung bean production under diverse environmental conditions.

Comprehensive analysis of the NAC transcription factor gene family in Kandelia obovata reveals potential members related to chilling tolerance

“…Our results indicated that 49 segmental duplications and 4 tandem duplications were detected in 79 KoNAC genes, which implied that segmental duplication was the main driving force for the expansion of the KoNAC gene family, similar to findings in V. radiate (Tariq et al, 2022). It was reported that K. obovata has undergone two polyploidization events: an ancient polyploidization event shared with most eudicots (g-event) and a recent wholegenome duplication (WGD)/segmental duplication shared with other Rhizophoreae plants (Hu et al, 2020).…”

“…It has been reported that tandem duplications play important roles in the expansion of the NAC family in O. sativa (Nuruzzaman et al, 2010), Solanum tuberosum (Singh et al, 2013) and Eucalyptus grandis (Hussey et al, 2015). Segmental duplications appear to be more dominant in the expansion of the NAC family, as observed in Panicum miliaceum (Shan et al, 2020), Raphanus sativus (Huang et al, 2022), and Vigna radiate (Tariq et al, 2022).…”

Identification of the NAC Transcription Factor Family during Early Seed Development in Akebia trifoliata (Thunb.) Koidz

“…We identified 101 AktNAC genes encoding these protein families, a number close to Arabidopsis thaliana (105) [ 37 ] and pepper (104) [ 45 ], but less than rice (151) [ 9 ] and maize (152) [ 46 ], and more than grape (74) [ 47 ] and mung bean (81) [ 48 ]. These results suggest that the number of NAC gene families varies across species, which may be due to the evolutionary expansion of NAC gene families.…”

Transcriptomic and biochemical analyses of drought response mechanism in mung bean (Vignaradiata (L.) Wilczek) leaves

“…Due to its high protein content in seeds and sprouts, mung bean has become more popular, and the planting area has increased in recent years [ 10 ]. Mung bean is widely cultivated in dry regions, as it is highly resistant to drought conditions [ 11 ]. Transcriptome analysis is typically used to reveal gene networks, and transcriptome analysis combined with physiological and biochemical indicators can help identify candidate genes for drought tolerance [ 12 – 14 ].…”