Genome-Wide Identification and Expression Analysis of the NAC Gene Family in Alfalfa Revealed Its Potential Roles in Response to Multiple Abiotic Stresses

Abstract

NAC (NAM, ATAF1/2, and CUC2) transcription factors compose one of the largest families of plant-specific transcription factors; they are widely involved in plant growth and development and have especially important roles in improving stress resistance in plants. However, NAC gene family members in alfalfa (Medicago sativa L.) have not been systematically identified and analyzed genome-wide due to the complexity of the alfalfa reference genome. In this study, a total of 421 M. sativa NAC genes (MsNACs) were identified from the alfalfa “Xinjiangdaye” reference genome. Basic bioinformatics analysis, including characterization of sequence length, protein molecular weight and genome position and conserved motif analysis, was conducted. Expression analysis showed that 47 MsNACs had tissue-specific expression, and 64 MsNACs were expressed in all tissues. The transcriptomic profiles of the genes were very different, indicating that these MsNACs have various functions in alfalfa growth and development. We identified 25, 42 and 47 MsNACs that respond to cold, drought and salt stress based on transcriptome data analysis and real-time quantitative PCR (RT–qPCR). Furthermore, 22 MsNACs were found to respond to both salt and drought stress, and 15 MsNACs were found to respond to cold, salt and drought stress. The results of this study could provide valuable information for further functional analysis of MsNACs and for the improvement of stress resistance in alfalfa.

Transcriptome-wide identification of NAC (no apical meristem/Arabidopsis transcription activation factor/cup-shaped cotyledon) transcription factors potentially involved in salt stress response in garlic

“…In this study, most of the AsNAC proteins had all of the five subdomains, whereas some domain regions were incomplete in the minority proteins. Similar results were also observed in some previous studies ( He et al, 2022 ; Yang et al, 2022 ), indicating that some NAC proteins possessed preternatural structures and unique functions. It is reported that subdomains A, C, and D are more conserved than B and E ( Ooka et al, 2003 ; Wang et al, 2016 ).…”

Characterization of NAC Gene Family in Ammopiptanthus mongolicus and Functional Analysis of AmNAC24, an Osmotic and Cold-Stress-Induced NAC Gene

“…Here, 86 NAC proteins were identified in A. mongolicus. Compared with the genomes of other species, the count of NAC genes in other species such as M. sativa [58], Glycine max [59], Dendrobium officinale [60], and Zanthoxylum bungeanum [29] stands at 421, 269, 111, and 109, respectively. A. mongolicus exhibits a relatively modest count of NAC family members compared to these plants, potentially indicative of evolutionary adaptations in distinct species amid varying habitat conditions.…”

Genome-wide identification and expression profiles analysis of the authentic response regulator gene family in licorice

“…Gene duplication events act as a significant factor in expansions and realignments of genomes ( Rehman et al., 2022 ). Plenty of transcription factor families have been reported to experience gene duplication events, like bHLH, NAC, and R2R3-MYB families ( He et al., 2022 ; Liang et al., 2023 ; Yang et al., 2023 ). We found 3, 5, and 6 pairs of segmental duplication events in GuARRs , GiARRs , and GgARRs , respectively ( Figure 5 ), while there were no tandem duplications identified, indicating that segmental duplications were the main driving force for the expansion of licorice ARR genes.…”