Salinization seriously threatens land use efficiency and crop yields across the world. Understanding the mechanisms plants use to protect against salt stress will help breeders develop salt-tolerant vegetable crops. Okra (Abelmoschus esculentus L.) is an important vegetable crop of the mallow family, which is now cultivated in warm regions worldwide. To understand the effects of salt stress on the protein level of okra, a comparative proteomic analysis of okra seedlings grown in the presence of 0 or 300 mmol L− 1 NaCl treatment was performed using an integrated approach of Tandem Mass Tag labeling and LC-MS/MS integrated approach. A total of 7179 proteins were identified in this study, for which quantitative information was available for 5774 proteins. In the NaCl/control comparison group, there were 317 differentially expressed proteins (DEPs), of which 165 proteins were upregulated and 152 proteins downregulated in the presence of NaCl. Based on the above data, we carried out a systematic bioinformatics analysis of proteins with information, including protein annotation, domain characteristics, functional classification, and pathway enrichment. Enriched gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the DEPs were most strongly associated with “response to stress” and “protein processing in endoplasmic reticulum”. Furthermore, several heat shock proteins were identified as DEPs. This information provides a reference direction for further research on the okra proteome in the downstream of the salt stress response, with our data revealing that the responses of okra to salt stress involves by various pathways.

Wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) is the world’s most widely cultivated crop and an important staple food for humans, accounting for one-fifth of calories consumed. Proteins encoded by the regulator of chromosome condensation 1 (RCC1) are highly conserved among eukaryotes and consist of seven repeated domains that fold into a seven-bladed propeller structure. In this study, a total of 76 RCC1 genes of bread wheat were identified via a genome-wide search, and their phylogenetic relationship, gene structure, protein-conserved domain, chromosome localization, conserved motif, and transcription factor binding sites were systematically analyzed using the bioinformatics approach to indicate the evolutionary and functional features of these genes. The expression patterns of 76 TaRCC1 family genes in wheat under various stresses were further analyzed, and RT-PCR verified that RCC1-3A (TraesCS3A02G362800), RCC1-3B (TraesCS3B02G395200), and RCC1-3D (TraesCS3D02G35650) were significantly induced by salt, cold, and drought stresses. Additionally, the co-expression network analysis and binding site prediction suggested that Myb-7B (TraesCS7B02G188000) and Myb-7D (TraesCS7D02G295400) may bind to the promoter of RCC1-3A/3B and upregulate their expression in response to abiotic stresses in wheat. The results have furthered our understanding of the wheat RCC1 family members and will provide important information for subsequent studies and the use of RCC1 genes in wheat.

The regulator of chromosome condensation 1 (RCC1) is the nucleotide exchange factor for a GTPase called the Ras-related nuclear protein, and it is important for nucleo-plasmic transport, mitosis, nuclear membrane assembly, and control of chromatin agglutination during the S phase of mitosis in animals. In plants, RCC1 molecules act mainly as regulating factors for a series of downstream genes during biological processes such as the ultraviolet-B radiation (UV-B) response and cold tolerance. In this study, 56 genes were identified in upland cotton by searching the associated reference genomes. The genes were found to be unevenly distributed on 26 chromosomes, except A06, A12, D03, and D12. Phylogenetic analysis by maximum-likelihood revealed that the genes were divided into five subgroups. The RCC1 genes within the same group shared similar exon/intron patterns and conserved motifs in their encoded proteins. Most genes of the RCC1 family are expressed differently under various hormone treatments and are negatively controlled by salt stress. Gh_A05G3028 and Gh_D10G2310, which encode two proteins located in the nucleus, were strongly induced under salt treatment, while mutants of their homoeologous gene (UVR8) in Arabidopsis and VIGS (virus induced gene silencing) lines of the two genes above in G. hirsutum exhibited a salt-sensitive phenotype indicating their potential role in salt resistance in cotton. These results provide valuable reference data for further study of RCC1 genes in cotton.

Soil salinization is a major environmental stresses that seriously threatens land use efficiency and crop yields worldwide. Although the overall response of plants to NaCl has been well studied, the contribution of protein phosphorylation to the detoxification and tolerance of NaCl in okra (Abelmoschus esculentus L.) seedlings is unclear. The molecular bases of okra seedlings’ responses to 300 mM NaCl stress are discussed in this study. Using a combination of affinity enrichment, tandem mass tag (TMT) labeling and high-performance liquid chromatography–tandem mass spectrometry analysis, a large-scale phosphoproteome analysis was performed in okra. A total of 4341 phosphorylation sites were identified on 2550 proteins, of which 3453 sites of 2268 proteins provided quantitative information. We found that 91 sites were upregulated and 307 sites were downregulated in the NaCl/control comparison group. Subsequently, we performed a systematic bioinformatics analysis including gene ontology annotation, domain annotation, subcellular localization, and Kyoto Encyclopedia of Genes and Genomes pathway annotation. The latter revealed that the differentially expressed proteins were most strongly associated with ‘photosynthesis antenna proteins’ and ‘RNA degradation’. These differentially expressed proteins probably play important roles in salt stress responses in okra. The results should help to increase our understanding of the molecular mechanisms of plant post-translational modifications in response to salt stress.

Saline stress is a significant factor that caused crop growth inhibition and yield decline. SHORT INTERNODES/STYLISH (SHI/STY) and SHI-RELATED SEQUENCE (SRS) transcription factors are specific to plants and share a conserved RING-like zinc-finger domain (CX₂CX₇CX₄CX₂C₂X₆C). However, the functions of SHI/STY and SRS genes in cotton responses to salt stress remain unclear. In this study, 26 GhSRSs were identified in Gossypium hirsutum, which further divided into three subgroups. Phylogenetic analysis of 88 SRSs from8 plant species revealed independent evolutionary pattern in some of SRSs derived from monocots. Conserved domain and subcellular location predication of GhSRSs suggested all of them only contained the conserved RING-like zinc-finger domain (DUF702) domain and belonged to nucleus-localized transcription factors except for the GhSRS22. Furthermore, synteny analysis showed structural variation on chromosomes during the process of cotton polyploidization. Subsequently, expression patterns of GhSRS family members in response to salt and drought stress were analyzed in G. hirsutum and identified a salt stress-inducible gene GhSRS21. The GhSRS21 was proved to localize in the nuclear and silencing it in G. hirsutum increased the cotton resistance to salt using the virus-induced gene silencing (VIGS) system. Finally, our transcriptomic data revealed that GhSRS21 negatively controlled cotton salt tolerance by regulating the balance between ROS production and scavenging. These results will increase our understanding of the SRS gene family in cotton and provide the candidate resistant gene for cotton breeding.