Comparative physiology and transcriptome response patterns in cold-tolerant and cold-sensitive varieties of Solanum melongena.

BACKGROUND: Climate change has led to severe cold events, adversely impacting global crop production. Eggplant (Solanum melongena L.), a significant economic crop, is highly susceptible to cold damage, affecting both yield and quality. Unraveling the molecular mechanisms governing cold resistance, including the identification of key genes and comprehensive transcriptional regulatory pathways, is crucial for developing new varieties with enhanced tolerance. RESULTS: In this study, we conducted a comparative analysis of leaf physiological indices and transcriptome sequencing results. The orthogonal partial least squares discriminant analysis (OPLS-DA) highlighted peroxidase (POD) activity and soluble protein as crucial physiological indicators for both varieties. RNA-seq data analysis revealed that a total of 7024 and 6209 differentially expressed genes (DEGs) were identified from variety "A" and variety "B", respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment of DEGs demonstrated that the significant roles of starch and sucrose metabolism, glutathione metabolism, terpenoid synthesis, and energy metabolism (sucrose and starch metabolism) were the key pathways in eggplant. Weighted gene co-expression network analysis (WGCNA) shown that the enrichment of numerous cold-responsive genes, pathways, and soluble proteins in the MEgrep60 modules. Core hub genes identified in the co-expression network included POD, membrane transporter-related gene MDR1, abscisic acid-related genes, growth factor enrichment gene DELLA, core components of the biological clock PRR7, and five transcription factors. Among these, the core transcription factor MYB demonstrated co-expression with signal transduction, plant hormone, biosynthesis, and metabolism-related genes, suggesting a pivotal role in the cold response network. CONCLUSION: This study integrates physiological indicators and transcriptomics to unveil the molecular mechanisms responsible for the differences in cold tolerance between the eggplant cold-tolerant variety "A" and the cold-sensitive variety "B". These mechanisms include modulation of reactive oxygen species (ROS), elevation in osmotic carbohydrate and free proline content, and the expression of terpenoid synthesis genes. This comprehensive understanding contributes valuable insights into the molecular underpinnings of cold stress tolerance, ultimately aiding in the improvement of crop cold tolerance.

Identification and Molecular Characterization of the CAMTA Gene Family in Solanaceae with a Focus on the Expression Analysis of Eggplant Genes under Cold Stress.

Calmodulin-binding transcription activator (CAMTA) is an important calmodulin-binding protein with a conserved structure in eukaryotes which is widely involved in plant stress response, growth and development, hormone signal transduction, and other biological processes. Although CAMTA genes have been identified and characterized in many plant species, a systematic and comprehensive analysis of CAMTA genes in the Solanaceae genome is performed for the first time in this study. A total of 28 CAMTA genes were identified using bioinformatics tools, and the biochemical/physicochemical properties of these proteins were investigated. CAMTA genes were categorized into three major groups according to phylogenetic analysis. Tissue-expression profiles indicated divergent spatiotemporal expression patterns of SmCAMTAs. Furthermore, transcriptome analysis of SmCAMTA genes showed that exposure to cold induced differential expression of many eggplant CAMTA genes. Yeast two-hybrid and bimolecular fluorescent complementary assays suggested an interaction between SmCAMTA2 and SmERF1, promoting the transcription of the cold key factor SmCBF2, which may be an important mechanism for plant cold resistance. In summary, our results provide essential information for further functional research on Solanaceae family genes, and possibly other plant families, in the determination of the development of plants.

Regulation of a novel DsGATA1 from Dunaliella salina on the synthesis of carotenoids under red light.

Dunaliella salina is a high-quality industrial effector for carotenoid production. The mechanism by which red light regulates carotenoid synthesis is still unclear. In this study, a transcription factor of DsGATA1 with a distinct structure was discovered in D. salina. The recognition motif of DsGATA1 was comparable to that of plant and fungal GATA, despite its evolutionary proximity to animal-derived GATA. The expression of DsGATA1 in D. salina was still noticeably decreased when exposed to red light. Analysis of physiological and biochemical transcriptomic data from overexpressed, interfering, and wild-type strains of DsGATA1 revealed that DsGATA1 acts as a global regulator of D. salina carotenoid synthesis. The upregulated genes in the CBP pathway by DsGATA1 were involved in its regulation of the synthesis of carotenoids. DsGATA1 also enhanced carotenoid accumulation under red light by affecting N metabolism. DsGATA1 was found to directly bind to the promoter of nitrate reductase to activate its expression, promoting D. salina nitrate uptake and accelerating biomass accumulation. DsGATA1 affected the expression of the genes encoding GOGAT, GDH, and ammonia transporter proteins. Moreover, our study revealed that the regulation of N metabolism by DsGATA1 led to the production of NO molecules that inhibited carotenoid synthesis. However, DsGATA1 significantly enhanced carotenoid synthesis by NO scavenger removal of NO. The D. salina carotenoid accumulation under red light was elevated by 46% in the presence of overexpression of DsGATA1 and NO scavenger. Nevertheless, our results indicated that DsGATA1 could be an important target for engineering carotenoid production. KEY POINTS: • DsGATA1 with a distinct structure and recognition motif was found in D. salina • DsGATA1 enhanced carotenoid production and biomass in D. salina under red light • DsGATA1 is involved in the regulation of N metabolism and carotenoid synthesis.

Distribution, characterization, and evolution of heavy metal resistance genes and Tn7-like associated heavy metal resistance Gene Island of Burkholderia.

Introduction: Burkholderia is a rod-shaped aerobic Gram-negative bacteria with considerable genetic and metabolic diversity, which can beused for bioremediation and production applications, and has great biotechnology potential. However, there are few studies on the heavy metal resistance of the Burkholderia genus. Methods: In this paper, the distribution, characteristics and evolution of heavy metal resistance genes in Burkholderia and the gene island of Tn7-like transposable element associated with heavy metal resistance genes in Burkholderia were studied by comparative genomic method based on the characteristics of heavy metal resistance. Results and discussion: The classification status of some species of the Burkholderia genus was improved, and it was found that Burkholderia dabaoshanensis and Burkholderia novacaledonica do not belong to the Burkholderia genus.Secondly, comparative genomics studies and pan-genome analysis found that the core genome of Burkholderia has alarger proportion of heavy metal resistance genes and a greater variety of heavy metalresistance genes than the subsidiary genome and strain specific genes. Heavy metal resistance genes are mostly distributed in the genome in the form of various gene clusters (for example, mer clusters, ars clusters, czc/cusABC clusters). At the same time, transposase, recombinase, integrase and other genes were foundupstream and downstream of heavy metal gene clusters, indicating that heavy metal resistance genes may beobtained through horizontal transfer. The analysis of natural selection pressure of heavy metal resistance genes showed that heavy metal resistance genes experienced strong purification selection under purification selection pressure in the genome.The Tn7 like transposable element of Burkholderia was associated with the heavy metal resistance gene island, and there were a large number of Tn7 transposable element insertion events in genomes. At the same time, BGI metal gene islands related to heavy metal resistance genes of Tn7 like transposable element were found, and these gene islands were only distributed in Burkholderia cepacia, Burkholderia polyvora, and Burkholderia contaminant.

DsLCYB Directionally Modulated ß-Carotene of the Green Alga Dunaliella salina under Red Light Stress.

Carotenoids, which are natural pigments found abundantly in wide-ranging species, have diverse functions and high industrial potential. The carotenoid biosynthesis pathway is very complex and has multiple branches, while the accumulation of certain metabolites often affects other metabolites in this pathway. The DsLCYB gene that encodes lycopene cyclase was selected in this study to evaluate ß-carotene production and the accumulation of ß-carotene in the alga Dunaliella salina. Compared with the wild type, the transgenic algal species overexpressed the DsLCYB gene, resulting in a significant enhancement of the total carotenoid content, with the total amount reaching 8.46 mg/g for an increase of up to 1.26-fold. Interestingly, the production of α-carotene in the transformant was not significantly reduced. This result indicated that the regulation of DsLCYB on the metabolic flux distribution of carotenoid biosynthesis is directional. Moreover, the effects of different light-quality conditions on ß-carotene production in D. salina strains were investigated. The results showed that the carotenoid components of ß-carotene and ß-cryptoxanthin were 1.8-fold and 1.23-fold higher than that in the wild type under red light stress, respectively. This suggests that the accumulation of ß-carotene under red light conditions is potentially more profitable.

Phylogenetic, Structural and Functional Evolution of the LHC Gene Family in Plant Species.

Light-harvesting chlorophyll a/b-binding (LHC) superfamily proteins play a vital role in photosynthesis. Although the physiological and biochemical functions of LHC genes have been well-characterized, the structural evolution and functional differentiation of the products need to be further studied. In this paper, we report the genome-wide identification and phylogenetic analysis of LHC genes in photosynthetic organisms. A total of 1222 non-redundant members of the LHC family were identified from 42 species. According to the phylogenetic clustering of their homologues with Arabidopsis thaliana, they can be divided into four subfamilies. In the subsequent evolution of land plants, a whole-genome replication (WGD) event was the driving force for the evolution and expansion of the LHC superfamily, with its copy numbers rapidly increasing in angiosperms. The selection pressure of photosystem II sub-unit S (PsbS) and ferrochelatase (FCII) families were higher than other subfamilies. In addition, the transcriptional expression profiles of LHC gene family members in different tissues and their expression patterns under exogenous abiotic stress conditions significantly differed, and the LHC genes are highly expressed in mature leaves, which is consistent with the conclusion that LHC is mainly involved in the capture and transmission of light energy in photosynthesis. According to the expression pattern and copy number of LHC genes in land plants, we propose different evolutionary trajectories in this gene family. This study provides a basis for understanding the molecular evolutionary characteristics and evolution patterns of plant LHCs.

Characterization and diverse evolution patterns of glycerol-3-phosphate dehydrogenase family genes in Dunaliella salina.

The glycerol-3-phosphate dehydrogenase (GPD) gene family plays a major role in glycerol synthesis and adaptation to abiotic stresses. Few studies on GPD family genes from the halotolerant algae Dunaliella salina are available. In this study, seven DsaGPD genes were identified by mining D. salina sequencing data. Among them, DsaGPD5 contained the canonical NAD+-GPD protein domain, called si-GPD. In comparison, DsaGPD1-4 not only contained the canonical NAD+-GPD domain but also a unique domain, the haloacid dehalogenase (HAD)-like superfamily domain, in their N-terminal region, called bi-GPD. DsaGPD6, 7 contained the FAD+-GPD domain. In the transient expression system, DsaGPD1, 3, 4 were found in the cytosol of Arabidopsis thaliana protoplast, DsaGPD2, 5 in the chloroplast, and DsaGPD6, 7 in the mitochondria. MEME analysis showed that six conserved motifs were present in both si-GPDs and bi-GPDs, whereas seven highly conserved motifs were only present in bi-GPDs. The quantitative real-time PCR results showed significant induction of the DsaGPD genes under abiotic stresses, indicating their tolerance-related role in D. salina. DsaGPD2 and DsaGPD5 may be the osmoregulator form and glyceride form in the chloroplast, respectively. The evolutionary forces acting on si-GPDs and bi-GPDs were different in the same organism: bi-GPDs were under purifying selection, while si-GPDs were mainly under positive selection. Furthermore, evolution of the N_HAD domain and C_GPD domain in bi-GPDs is highly correlated. In summary, this study characterizes DsaGPD gene family members and provides useful information for elucidating the salt tolerance mechanism in D. salina.

Characterization of the complete mitochondrial genome and phylogenetic analysis of Prototheca stagnorum (chlorellales: Chlorellaceae).

Prototheca stagnorum belongs to the genus Prototheca that are achloroplyllous algae with phylogenetic affinities to Chlorella sp. Microalgae of the genus Prototheca spp are associated with rare algal infections of invertebrates termed protothecosis. In this study, the complete nucleotide sequence of the circular mitochondrial (mt) DNA of the chlorophyte alga P. stagnorum has been determined (80,023 base-pairs, A + T content 13.77%). The genes identified encode three subunits of the cytochrome oxidase and apocytochrome b, eight subunits of the NADH dehydrogenase complex (nad1-7, nad4L), four ATPase subunits (atp1, atp4, atp6, atp8), three ribosomal RNAs (5 S (rrn5), small subunit (srn) and large subunit (lrn) RNA), 27 tRNAs, two succinate dehydrogenase and 10 ribosome proteins. The complete mitochondrial genome sequence will provide new molecular biology information to further understand the genetic diversity of the Prototheca sp. and to eliminate this population.

The complete mitochondrial genome of Psammomys obesus (Rodentia: Muridae).

The fat sand rats (Psammomys obesus) can easily induce obesity and acquire type 2 diabetes mellitus when they are fed with high-carbohydrate diets. P. obesus is often used as an animal model for studies on diabetes and obesity. We described 16,592 bp of P. obesus mtDNA that contains 13 protein-coding genes (PGCs), two rRNA genes (12S rRNA and 16S rRNA), 22 transfer RNA (tRNA) genes, and one control region (D-loop). The complete mitochondrial genome sequence provided here would be useful for further understanding the evolution of ratite and conservation genetics of P. obesus.

The complete mitochondrial genome of Megaderma lyra (Indian false vampire).

The Indian false vampire (Megaderma lyra), known as the greater false vampire bat, the Indian false vampire bat, and the greater false-vampire, is typical echolocation mammals. It has been listed in the IUCN Red List of threatened species and included in the Red Book of Endangered Animals in China. Herein, we described 17,055 bp of M. lyra mtDNA that includes 13 protein-coding genes (PGCs), two rRNA genes (12S rRNA and 16S rRNA), 22 transfer RNA (tRNA) genes, and one control region (D-loop). The complete mitochondrial genome sequence will provide new molecular biology information to further understand the genetic diversity of the M. lyra and to protect this population.

Comparative genomic analysis of Paenibacillus sp. SSG-1 and its closely related strains reveals the effect of glycometabolism on environmental adaptation.

The extensive environmental adaptability of the genus Paenibacillus is related to the enormous diversity of its gene repertoires. Paenibacillus sp. SSG-1 has previously been reported, and its agar-degradation trait has attracted our attention. Here, the genome sequence of Paenibacillus sp. SSG-1, together with 76 previously sequenced strains, was comparatively studied. The results show that the pan-genome of Paenibacillus is open and indicate that the current taxonomy of this genus is incorrect. The incessant flux of gene repertoires resulting from the processes of gain and loss largely contributed to the difference in genomic content and genome size in Paenibacillus. Furthermore, a large number of genes gained are associated with carbohydrate transport and metabolism. It indicates that the evolution of glycometabolism is a key factor for the environmental adaptability of Paenibacillus species. Interestingly, through horizontal gene transfer, Paenibacillus sp. SSG-1 acquired an approximately 150 kb DNA fragment and shows an agar-degrading characteristic distinct from most other non-marine bacteria. This region may be transported in bacteria as a complete unit responsible for agar degradation. Taken together, these results provide insights into the evolutionary pattern of Paenibacillus and have implications for studies on the taxonomy and functional genomics of this genus.

Quality of life estimate in stomach, colon, and rectal cancer patients in a hospital in China.

The objective of this study was to investigate the outcome and coping patterns of patients with stomach, colon, and rectal cancer in a hospital in China. Health-related quality of life was assessed in 118 stomach, colon, and rectal cancer patients in Chinese People's Liberation Army General Hospital, Beijing, China, using the generic version of the European Organization for Research and Treatment of Cancer Quality of Life (QOL) Questionnaire Core 30 Items, Self-rated Anxiety Scores (SAS), Self-rated Depression Scores (SDS), Medical Coping Modes of Questionnaire (MCMQ), and Social Support Requirement Scale (SSRS) questionnaires. The overall QOL was 50.7 ± 6.5, 48.1 ± 7.7, and 47.6 ± 6.4, respectively, for stomach, colon, and rectal cancer groups. Correlations between QOL and SAS and SDS in stomach cancer patients were significantly higher than observed in the cohort of colon or rectal cancer patients (Spearman coefficient of 0.366 and 0.129, respectively). Cluster analysis of MCMQ data revealed four identifiable patterns (resign, confront, avoid-confront, and avoid-resign) of coping in the study group. Subjective support was significantly higher than objective support (p < 0.05); however, extent of using the support was significantly lower than either objective (p < 0.05) or subjective support (p < 0.01). SAS and SDS were negatively correlated to SSRS scores (p < 0.01 and p < 0.05, respectively). Stomach, colon, and rectal cancer patients had anxiety and depression stemming from their cancer diagnosis and postdiagnosis treatment, and sex dependency was prevalent in SSRS response. Coping patterns were reliable indicators of psychosocial side effects in patients with stomach, colon, and rectal cancers.