Genome-Wide Analysis of the Role of NAC Family in Flower Development and Abiotic Stress Responses in Cleistogenes songorica

Abstract

Plant-specific NAC (NAM, ATAF, CUC) transcription factor (TF) family plays important roles in biological processes such as plant growth and response to stress. Nevertheless, no information is known about NAC TFs in Cleistogenes songorica, a prominent xerophyte desert grass in northwestern China. In this study, 162 NAC genes were found from the Cleistogenes songorica genome, among which 156 C. songoricaNAC (CsNAC) genes (96.3%) were mapped onto 20 chromosomes. The phylogenetic tree constructed by CsNAC and rice NAC TFs can be separated into 14 subfamilies. Syntenic and Ka/Ks analyses showed that CsNACs were primarily expanded by genomewide replication events, and purifying selection was the primary force driving the evolution of CsNAC family genes. The CsNAC gene expression profiles showed that 36 CsNAC genes showed differential expression between cleistogamous (CL) and chasmogamous (CH) flowers. One hundred and two CsNAC genes showed differential expression under heat, cold, drought, salt and ABA treatment. Twenty-three CsNAC genes were commonly differentially expressed both under stress responses and during dimorphic floret development. Gene Ontology (GO) annotation, coexpression network and qRT-PCR tests revealed that these CsNAC genes may simultaneously regulate dimorphic floret development and the response to stress. Our results may help to characterize the NAC transcription factors in C. songorica and provide new insights into the functional research and application of the NAC family in crop improvement, especially in dimorphic floret plants.

Genome-Wide Analysis and Expression Profiles of the Dof Family in Cleistogenes songorica under Temperature, Salt and ABA Treatment

“…About 2/3 CsDof genes are syntentic, and most paralogous gene pairs existed on different chromosomes ( Figure 2 ). The result is similar to gene families CsNAC and bZIP , and it has been reported that the expansion of bZIP and CsNAC gene families were produced by whole-genome duplication events [ 3 , 45 ]. These inferred that the expansion of the C. songorica CsDof gene family was also caused by whole-genome duplication events.…”

“…Gene duplication is a mechanism for gene family expansion and new gene generation. In many plants, gene family expansion is primarily involved in segmental duplication, tandem duplication, and transposition events [ 45 ]. Syntentic analysis is usually used to identify the evolutionary relationship between genes.…”

Genome-Wide Identification of NAC Transcription Factor Family in Juglans mandshurica and Their Expression Analysis during the Fruit Development and Ripening

“…Owing to their crucial function in the formation of the embryos and flowers of petunias, NAC TFs were widely studied, and multiple reports identified its key role in plant growth and development [12,13]. A large number of NAC-encoding genes have been identified and confirmed in various plants for their role in regulating wood formation [14], leaf senescence [15], fruit development [16,17], and flower morphogenesis [18,19]. Furthermore, NAC TFs also are involved in various biotic and abiotic stress responses in many plants such as Populus tomentosa [20], Arabidopsis thaliana [21], Oryza sativa [22,23], Glycine max [24], Arachis hypogaea [25], and Xanthoceras sorbifolia [26].…”

Genome-wide identification and expression analysis of the NAC transcription factor family in Saccharum spontaneum under different stresses

“… 38 Whole-genome analysis of the NAC gene family has been conducted in species that have been sequenced, including O. sativa , 22 Z. mays , 23 ,24 S. bicolor , 25 Triticum aestivum L., 39 Musa acuminata , 40 Vaccinium corymbosum L., 41 Juglans mandshurica , 42 Cleistogenes songorica , and Coffea canephora . 43 , 44 The identification and analysis of S. spontaneum NAC gene families at the whole-genome level have not been reported. Therefore, the purpose of this study was to study the characteristics of SsNAC genes at the genomic level and to provide a reference for further analysis of the potential function of NAC genes.…”