NODULE-INCEPTION (NIN)-like proteins (NLPs) are critical in regulating nitrogen (N) use in plants. Although NLPs are well-studied in various species, their characterization in mungbean (Vigna radiata L.) remains limited. The identified VrNLPs totaling seven shared similarities in their physicochemical properties with Arabidopsis thaliana NLPs (AtNLPs). A comparison of conserved domains confirmed that VrNLPs, like AtNLPs, contain both the RWP-RK and PB1 domains, verifying their membership in the same gene family. Analysis of gene structures revealed similar exon-intron patterns between VrNLPs and AtNLPs; although, VrNLPs had shorter gene lengths. In contrast, the average protein lengths of VrNLPs showed higher similarity to those of AtNLPs. Both sets of proteins appeared to be hydrophilic, as indicated by the negative Grand Average of Hydropathicity (GRAVY) values. Subcellular localization analysis indicated that all VrNLPs are nuclear-localized. Overall, VrNLPs and AtNLPs share substantial homology in gene structure, protein domains, motifs, and physicochemical attributes. The phylogenetic analysis exhibited VrNLPs and AtNLPs as closest relatives, suggesting their evolution from a common ancestor alongside NLPs from other vascular and non-vascular plants (Oryza sativa, Zea mays, and Physcomitrella patens). An improved nitrogen use efficiency (NUE) could lead to higher yields with reduced fertilizer input, mitigating environmental pollution from excessive fertilizer use.
mungbean, nitrogen, nitrogen use efficiency, Nodule Inception-like proteins, transcription factor
This study identified members of the NLP gene family in mungbean (Vigna radiata L.) and provided a preliminary functional overview of VrNLPs. With their structural and functional similarities with AtNLPs, VrNLPs showed promising potential for enhancing NUE in mungbeans through molecular plant breeding and genetic engineering.