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In this work, we demonstrate direct evidence of the antiamyloid potential of Cu(II) ions against amyloid formation of insulin. The Cu(II) ions were found to efficiently disassemble the preformed amyloid nanostructures into soluble species and suppress monomer fibrillation under aggregation-prone conditions. The direct interaction of Cu(II) ions with the cross-ß structure of amyloid fibrils causes substantial disruption of both the interchain and intrachain interactions, predominantly the H-bonds and hydrophobic contacts. Further, the Cu(II) ions show a strong affinity for the aggregation-prone conformers of the protein and inhibit their spontaneous self-assembly. These results reveal the possible molecular mechanism for the antiamyloidogenic potential of Cu(II) which could be important for the development of metal-ion specific therapeutic strategies against amyloid linked complications.
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Amiloide , Cobre , Insulina , Nanoestructuras , Cobre/química , Insulina/química , Amiloide/química , Nanoestructuras/química , Interacciones Hidrofóbicas e Hidrofílicas , Humanos , Enlace de HidrógenoRESUMEN
Maintaining duplicate germplasms in genebanks hampers effective conservation and utilization of genebank resources. The redundant germplasm adds to the cost of germplasm conservation by requiring a large proportion of the genebank financial resources towards conservation rather than enriching the diversity. Besides, genome-wide-association analysis using an association panel with over-represented germplasms can be biased resulting in spurious marker-trait associations. The conventional methods of germplasm duplicate removal using passport information suffer from incomplete or missing passport information and data handling errors at various stages of germplasm enrichment. This limitation is less likely in the case of genotypic data. Therefore, we developed a web-based tool, Germplasm Duplicate Identification and Removal Tool (G-DIRT), which allows germplasm duplicate identification based on identity-by-state analysis using single-nucleotide polymorphism genotyping information along with pre-processing of genotypic data. A homozygous genotypic difference threshold of 0.1% for germplasm duplicates has been determined using tetraploid wheat genotypic data with 94.97% of accuracy. Based on the genotypic difference, the tool also builds a dendrogram that can visually depict the relationship between genotypes. To overcome the constraint of high-dimensional genotypic data, an offline version of G-DIRT in the interface of R has also been developed. The G-DIRT is expected to help genebank curators, breeders and other researchers across the world in identifying germplasm duplicates from the global genebank collections by only using the easily sharable genotypic data instead of physically exchanging the seeds or propagating materials. The web server will complement the existing methods of germplasm duplicate identification based on passport or phenotypic information being freely accessible at http://webtools.nbpgr.ernet.in/gdirt/.
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Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Genotipo , Semillas/genéticaRESUMEN
BACKGROUND: Moth bean (Vigna aconitifolia) is an underutilized, protein-rich legume that is grown in arid and semi-arid areas of south Asia and is highly resistant to abiotic stresses such as heat and drought. Despite its economic importance, the crop remains unexplored at the genomic level for genetic diversity and trait mapping studies. To date, there is no report of SNP marker discovery and association mapping of any trait in this crop. Therefore, this study aimed to dissect the genetic diversity, population structure and marker-trait association for the flowering trait in a diversity panel of 428 moth bean accessions using genotyping by sequencing (GBS) approach. RESULTS: A total of 9078 high-quality single nucleotide polymorphisms (SNPs) were discovered by genotyping of 428 moth bean accessions. Model-based structure analysis and PCA grouped the moth bean accessions into two subpopulations. Cluster analysis revealed accessions belonging to the Northwestern region of India had higher variability than accessions from the other regions suggesting that this region represents its center of diversity. AMOVA revealed more variations within individuals (74%) and among the individuals (24%) than among the populations (2%). Marker-trait association analysis using seven multi-locus models including mrMLM, FASTmrEMMA FASTmrEMMA, ISIS EM-BLASSO, MLMM, BLINK and FarmCPU revealed 29 potential genomic regions for the trait days to 50% flowering, which were consistently detected in three or more models. Analysis of the allelic effect of the major genomic regions explaining phenotypic variance of more than 10% and those detected in at least 2 environments showed 4 genomic regions with significant phenotypic effect on this trait. Further, we also analyzed genetic relationships among the Vigna species using SNP markers. The genomic localization of moth bean SNPs on genomes of closely related Vigna species demonstrated that maximum numbers of SNPs were getting localized on Vigna mungo. This suggested that the moth bean is most closely related to V. mungo. CONCLUSION: Our study shows that the north-western regions of India represent the center of diversity of the moth bean. Further, the study revealed flowering-related genomic regions/candidate genes which can be potentially exploited in breeding programs to develop early-maturity moth bean varieties.
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Estudio de Asociación del Genoma Completo , Vigna , Vigna/genética , Genotipo , Fitomejoramiento , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
Removal of sugar as a sweetener and its replacement by a high potency sweetener introduces a number of sensory and technical challenges particularly diminution in mouthfeel. Thick consistency of pulpy fruits could be exploited to compensate for the loss of viscosity and mouthfeel in sugar substituted beverages. The investigation was undertaken to study the effect of mango pulp supplementation on the quality of flavoured low calorie milk drinks using sucralose as sugar substitute. The effect of 0.0 to 100 % sugar replacement on total solids (TS), total soluble solids (TSS), specific gravity, viscosity and sensory scores was studied. Sugar replacement considerably decreased TS, TSS, viscosity and sensory scores. The mango flavoured milk drinks(MFDs) prepared by replacing sugar with sucralose and adding 10 % mango pulp in milk of 0.5 % fat and 8.5 % milk solid-not-fat. MFD were pasteurized and stored at refrigeration temperature for shelf life studies. A significant (p < 0.01) loss in the viscosity, ascorbic acid and reducing sugar content of pasteurized MFD was noticed during the storage period of 10 days at 5.0 ± 0.1 °C. However, the titratable acidity increased to undesirable levels in MFD after 8 days which rendered it unacceptable. Standard plate count and yeast and mold count of MFDs increased during storage. The shelf life of the pasteurized MFD was found to be 8 days at 5.0 ± 0.1 °C.
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The study was undertaken to study the effect of heat treatment on the storage stability of cardamom flavoured low calorie milk drinks (CFDs). The drinks prepared by replacing sugar with sucralose and adding inulin in milk of 0.5 % fat and 8.5 % milk solid-not-fat were subjected to pasteurization and sterilization and stored at refrigeration and room temperature, respectively. The stored samples were evaluated for changes in physico-chemical and sensory attributes at regular intervals. In pasteurized drinks, the total solids (TS) and pH declined while the total soluble solids (TSS), titratable acidity and viscosity increased significantly (p < 0.01) with storage. A significant reduction in the flavour and body and mouthfeel scores was observed. Standard plate count (SPC) increased in both control and low calorie drinks with storage period. In sterilized CFDs, TS and TSS were not affected appreciably whereas titratable acidity increased and viscosity decreased significantly (p < 0.01) with storage. Though the sensory scores also declined with storage, the drinks obtained high acceptability scores even after 150 days of storage at room temperature. However, the changes in colour components (L, a and b values) indicated increased browning in the drinks with storage time. SPC was not detected until 120 days in control and 135 days in low calorie drink. Yeast and molds were not evident until 135 days in control and 150 days in low calorie drink. The shelf life was found to be 10 and 150 days of pasteurized and sterilized CFDs at refrigeration and room temperature, respectively.
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Pearl millet is a nutri-cereal that is mostly grown in harsh environments, making it an ideal crop to study heat tolerance mechanisms at the molecular level. Despite having a better-inbuilt tolerance to high temperatures than other crops, heat stress negatively affects the crop, posing a threat to productivity gain. Hence, to understand the heat-responsive genes, the leaf and root samples of two contrasting pearl millet inbreds, EGTB 1034 (heat tolerant) and EGTB 1091 (heat sensitive), were subjected to heat-treated conditions and generated genome-wide transcriptomes. We discovered 13,464 differentially expressed genes (DEGs), of which 6932 were down-regulated and 6532 up-regulated in leaf and root tissues. The pairwise analysis of the tissue-based transcriptome data of the two genotypes demonstrated distinctive genotype and tissue-specific expression of genes. The root exhibited a higher number of DEGs compared to the leaf, emphasizing different adaptive strategies of pearl millet. A large number of genes encoding ROS scavenging enzymes, WRKY, NAC, enzymes involved in nutrient uptake, protein kinases, photosynthetic enzymes, and heat shock proteins (HSPs) and several transcription factors (TFs) involved in cross-talking of temperature stress responsive mechanisms were activated in the stress conditions. Ribosomal proteins emerged as pivotal hub genes, highly interactive with key genes expressed and involved in heat stress response. The synthesis of secondary metabolites and metabolic pathways of pearl millet were significantly enriched under heat stress. Comparative synteny analysis of HSPs and TFs in the foxtail millet genome demonstrated greater collinearity with pearl millet compared to proso millet, rice, sorghum, and maize. In this study, 1906 unannotated DEGs were identified, providing insight into novel participants in the molecular response to heat stress. The identified genes hold promise for expediting varietal development for heat tolerance in pearl millet and similar crops, fostering resilience and enhancing grain yield in heat-prone environments.
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The essential amino acid histidine plays a central role in the manifestation of several metabolic processes, including protein synthesis, enzyme-catalysis, and key biomolecular interactions. However, excess accumulation of histidine causes histidinemia, which shows brain-related medical complications, and the molecular mechanism of such histidine-linked complications is largely unknown. Here, we show that histidine undergoes a self-assembly process, leading to the formation of amyloid-like cytotoxic and catalytically active nanofibers. The kinetics of histidine self-assembly was favored in the presence of Mg(II) and Co(II) ions. Molecular dynamics data showed that preferential noncovalent interactions dominated by H-bonds between histidine molecules facilitate the formation of histidine nanofibers. The histidine nanofibers induced amyloid cross-seeding reactions in several proteins and peptides including pathogenic Aß1-42 and brain extract components. Further, the histidine nanofibers exhibited oxidase activity and enhanced the oxidation of neurotransmitters. Cell-based studies confirmed the cellular internalization of histidine nanofibers in SH-SY5Y cells and subsequent cytotoxic effects through necrosis and apoptosis-mediated cell death. Since several complications including behavioral abnormality, developmental delay, and neurological disabilities are directly linked to abnormal accumulation of histidine, our findings provide a foundational understanding of the mechanism of histidine-related complications. Further, the ability of histidine nanofibers to catalyze amyloid seeding and oxidation reactions is equally important for both biological and materials science research.
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Nanofibras , Nanoestructuras , Neuroblastoma , Humanos , Histidina , Péptidos/química , Nanofibras/química , Amiloide/química , Péptidos beta-Amiloides/químicaRESUMEN
Curcumin is an important food additive that shows multiple medical-benefits including anticarcinogenic, anti-inflammatory, antibiotic and antiamyloid properties. However, understanding the mechanism of curcumin-mediated effects becomes rather complicated since it has low bio-viability and it undergoes autooxidation, influenced by temperature, pH and buffer. We find that curcumin's antiamyloid-potential is not primarily due to curcumin alone, rather due to a synergistic action of curcumin and its autooxidized-products generated during inhibition reactions. In physiological buffer curcumin undergoes thermally induced autooxidation and yields stable compounds which can synergistically work for both inhibition of amyloid aggregation and promotion of amyloid-disaggregation into soluble protein species. Curcumin also showed substantial inhibition effect against coaggregation of different food proteins. Curcumin's strong affinity for the hydrophobic moieties of the aggregation-prone partially-folded insulin structures seems crucial for the inhibition mechanism. Further, autooxidized curcumin products were found to protect UV-induced protein damage. The results provide conceptual foundations highlighting the link between chemistry and antiamyloid-activity of curcumin and may inspire curcumin-based therapeutics against amyloidogenesis.
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Curcumina , Curcumina/química , Amiloide/química , Proteínas Amiloidogénicas , Temperatura , AntiinflamatoriosRESUMEN
Recent discoveries on the self-assembly of aromatic amino acids into amyloid-like neurotoxic nanostructures have initiated a quest to decode the molecular mechanisms for the initiation of neurodegeneration. Moreover, the multicomponent nature of the amyloid deposits still questions the existing and well-defined amyloid cascade hypothesis. Hence, deciphering the neurotoxicity of amyloid-like nanostructures of aromatic amino acids becomes crucial for understanding the etiology of amyloidogenesis. Here, we demonstrate the cellular internalization and consequential damaging effects of self-assembled amyloid-like tryptophan nanostructures on human neuroblastoma cells. The cell-damaging potential of tryptophan nanostructure seems to be facilitated via ROS generation, necrosis and apoptosis mediated cell death. Further, tryptophan nanostructures were found to be seeding competent conformers, which triggered aggressive aggregation of brain extract components. The early stage intermediate nanostructures possess a higher cross-seeding efficacy than the seeding potential of the matured tryptophan fibrils. In addition to the cell-damaging and cross-seeding effects, tryptophan fibrils were found to catalyze oxidation of neuromodulator dopamine. These findings add more insights into the specific role of tryptophan self-assembly during the pathogenesis of hypertryptophanemia and other amyloid-associated neurodegenerative complications.
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Amiloide , Triptófano , Humanos , Amiloide/metabolismo , Proteínas Amiloidogénicas/metabolismo , Encéfalo/metabolismo , Aminoácidos AromáticosRESUMEN
Covalent tagging of fluorophores is central to the mechanistic understanding of important biological processes including protein-protein interaction and protein aggregation. Hence, studies on fluorophore-tagged peptides help in elucidating the molecular mechanism of amyloidogenesis, its cellular internalization, and crosstalk potential. Despite the many advantages the covalently tagged proteins offer, difficulties such as expensive and tedious synthesis and purification protocols have become a matter of concern. Importantly, covalently tagged fluorophores could introduce structural constraints, which may influence the conformation of the monomeric and aggregated forms of proteins. Here, we describe a robust-yet-simple method to make fluorescent-amyloid nanofibers through a coassembly-reaction route that does not alter the aggregation kinetics and the characteristic ß-sheet-conformers of resultant nanofibers. Fluorescent amyloid nanofibers derived from insulin, lysozyme, Aß1-42, and metabolites were successfully fabricated in our study. Importantly, the incorporated fluorophores exhibited remarkable stability, remaining intact without leaching even after undergoing serial dilutions and prolonged storage periods. This method enables monitoring of cellular internalization of the fluorescent-amyloid-nanofibers and the detection of FRET-signals during interfibrillar interactions. This simple and affordable protocol may significantly help amyloid researchers working on both in vitro and animal models.
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Nanofibras , Animales , Proteínas Amiloidogénicas , Colorantes Fluorescentes , Insulina , Insulina Regular HumanaRESUMEN
Wheat (Triticum aestivum L.) is a staple food crop for the global human population, and thus wheat breeders are consistently working to enhance its yield worldwide. In this study, we utilized a sub-set of Indian wheat mini core germplasm to underpin the genetic architecture for seed shape-associated traits. The wheat mini core subset (125 accessions) was genotyped using 35K SNP array and evaluated for grain shape traits such as grain length (GL), grain width (GW), grain length, width ratio (GLWR), and thousand grain weight (TGW) across the seven different environments (E1, E2, E3, E4, E5, E5, E6, and E7). Marker-trait associations were determined using a multi-locus random-SNP-effect Mixed Linear Model (mrMLM) program. A total of 160 non-redundant quantitative trait nucleotides (QTNs) were identified for four grain shape traits using two or more GWAS models. Among these 160 QTNs, 27, 36, 38, and 35 QTNs were associated for GL, GW, GLWR, and TGW respectively while 24 QTNs were associated with more than one trait. Of these 160 QTNs, 73 were detected in two or more environments and were considered reliable QTLs for the respective traits. A total of 135 associated QTNs were annotated and located within the genes, including ABC transporter, Cytochrome450, Thioredoxin_M-type, and hypothetical proteins. Furthermore, the expression pattern of annotated QTNs demonstrated that only 122 were differentially expressed, suggesting these could potentially be related to seed development. The genomic regions/candidate genes for grain size traits identified in the present study represent valuable genomic resources that can potentially be utilized in the markers-assisted breeding programs to develop high-yielding varieties.
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The study was undertaken to develop low calorie functional milk drinks using inulin and sucralose as fat and sugar substitutes, respectively. Cardamom was incorporated as a flavouring ingredient. The milk fat varied from 0.5 to 1.0%, sugar replacement from 0 to 100%, and inulin incorporation from 0 to 8%. The effect on total solids (TS), total soluble solids (TSS), specific gravity, viscosity and sensory scores was studied. Sugar replacement considerably decreased TS, TSS, viscosity and sensory scores. However, increase in inulin significantly improved these parameters. Addition of 4% inulin was found to impart viscosity and sensory properties equivalent to that of control (2% fat). The cardamom flavoured milk drinks were prepared by replacing sugar and adding 4% inulin in milk of 0.5% fat and 8.5% milk solid-not-fat. The calorific value decreased by 43% in the experimental milk drink compared to control.
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Recognition of pathogen-derived nucleic acids by host cells is an effective host strategy to detect pathogenic invasion and trigger immune responses. In the context of pathogen-specific pharmacology, there is a growing interest in mapping the interactions between pathogen-derived nucleic acids and host proteins. Insight into the principles of the structural and immunological mechanisms underlying such interactions and their roles in host defense is necessary to guide therapeutic intervention. Here, we discuss the newest advances in studies of molecular interactions involving pathogen nucleic acids and host factors, including their drug design, molecular structure and specific patterns. We observed that two groups of nucleic acid recognizing molecules, Toll-like receptors (TLRs) and the cytoplasmic retinoic acid-inducible gene (RIG)-I-like receptors (RLRs) form the backbone of host responses to pathogen nucleic acids, with additional support provided by absent in melanoma 2 (AIM2) and DNA-dependent activator of Interferons (IFNs)-regulatory factors (DAI) like cytosolic activity. We review the structural, immunological, and other biological aspects of these representative groups of molecules, especially in terms of their target specificity and affinity and challenges in leveraging host-pathogen protein-nucleic acid interactions (HP-PNI) in drug discovery.
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Nowadays, one of the most popular applications is cloud computing for storing data and information through World Wide Web. Since cloud computing has become available, users are rapidly increasing. Cloud computing enables users to obtain a better and more effective application at a lower cost in a more satisfactory way. Health services data must therefore be kept as safe and secure as possible because the release of this data could have serious consequences for patients. A framework for security and privacy must be employed to store and manage extremely sensitive data. Patients' confidential health records have been encrypted and saved in the cloud using cypher text so far. To ensure privacy and security in a cloud computing environment is a big issue. The medical system has been designed as a standard, access of records, and effective use by medical practitioners as required. In this paper, we propose a novel algorithm along with implementation details as an effective and secure E-health cloud model using identity-based cryptography. The comparison of the proposed and existing techniques has been carried out in terms of time taken for encryption and decryption, energy, and power. Decryption time has been decreased up to 50% with the proposed method of cryptography. As it will take less time for decryption, less power is consumed for doing the cryptography operations.
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Seguridad Computacional , Telemedicina , Algoritmos , Nube Computacional , Humanos , Proyectos de InvestigaciónRESUMEN
Globally, sodicity is one of the major abiotic stresses limiting the wheat productivity in arid and semi-arid regions. With due consideration, an investigation of the complex gene network associated with sodicity stress tolerance is required to identify transcriptional changes in plants during abiotic stress conditions. For this purpose, we sequenced the flag leaf transcriptome of a highly tolerant bread wheat germplasm (KRL 3-4) in order to extend our knowledge and better understanding of the molecular basis of sodicity tolerance. A total of 1,980 genes were differentially expressed in the flag leaf due to sodicity stress. Among these genes, 872 DEGs were upregulated and 1,108 were downregulated. Furthermore, annotation of DEGs revealed that a total of 1,384 genes were assigned to 2,267 GO terms corresponding to 502 (biological process), 638 (cellular component), and 1,127 (molecular function). GO annotation also revealed the involvement of genes related to several transcription factors; the important ones are expansins, peroxidase, glutathione-S-transferase, and metal ion transporters in response to sodicity. Additionally, from 127 KEGG pathways, only 40 were confidently enriched at a p-value <0.05 covering the five main KEGG categories of metabolism, i.e., environmental information processing, genetic information processing, organismal systems, and cellular processes. Most enriched pathways were prioritized using MapMan software and revealed that lipid metabolism, nutrient uptake, and protein homeostasis were paramount. We have also found 39 SNPs that mapped to the important sodicity stress-responsive genes associated with various pathways such as ROS scavenging, serine/threonine protein kinase, calcium signaling, and metal ion transporters. In a nutshell, only 19 important candidate genes contributing to sodicity tolerance in bread wheat were identified, and these genes might be helpful for better understanding and further improvement of sodicity tolerance in bread wheat.
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Ricebean (Vigna umbellata) is a lesser known pulse with well-recognized potential. Recently, it has emerged as a legume with endowed nutritional potential because of high concentration of quality protein and other vital nutrients in its seeds. However, the genes and pathways involved in regulating seed development and size are not understood in this crop. In our study, we analyzed the transcriptome of two genotypes with contrasting grain size (IC426787: large seeded and IC552985: small seeded) at two different time points, namely, 5 and 10 days post-anthesis (DPA). The bold seeded genotype across the time points (B5_B10) revealed 6,928 differentially expressed genes (DEGs), whereas the small seeded genotype across the time point (S5_S10) contributed to 14,544 DEGs. We have also identified several candidate genes for seed development-related traits like seed size and 100-seed weight. On the basis of similarity search and domain analysis, some candidate genes (PHO1, cytokinin dehydrogenase, A-type cytokinin, and ARR response negative regulator) related to 100-seed weight and seed size showed downregulation in the small seeded genotype. The MapMan and KEGG analysis confirmed that auxin and cytokinin pathways varied in both the contrasting genotypes and can therefore be the regulators of the seed size and other seed development-related traits in ricebeans. A total of 51 genes encoding SCF TIR1/AFB , Aux/IAA, ARFs, E3 ubiquitin transferase enzyme, and 26S proteasome showing distinct expression dynamics in bold and small genotypes were also identified. We have also validated randomly selected SSR markers in eight accessions of the Vigna species (V. umbellata: 6; Vigna radiata: 1; and Vigna mungo: 1). Cross-species transferability pattern of ricebean-derived SSR markers was higher in V. radiata (73.08%) than V. mungo (50%). To the best of our knowledge, this is the first transcriptomic study conducted in this crop to understand the molecular basis of any trait. It would provide us a comprehensive understanding of the complex transcriptome dynamics during the seed development and gene regulatory mechanism of the seed size determination in ricebeans.
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Resistance in modern wheat cultivars for stripe rust is not long lasting due to the narrow genetic base and periodical evolution of new pathogenic races. Though nearly 83 Yr genes conferring resistance to stripe rust have been cataloged so far, few of them have been mapped and utilized in breeding programs. Characterization of wheat germplasm for novel sources of resistance and their incorporation into elite cultivars is required to achieve durable resistance and thus to minimize the yield losses. Here, a genome-wide association study (GWAS) was performed on a set of 391 germplasm lines with the aim to identify quantitative trait loci (QTL) using 35K Axiom® array. Phenotypic evaluation disease severity against four stripe rust pathotypes, i.e., 46S119, 110S119, 238S119, and 47S103 (T) at the seedling stage in a greenhouse providing optimal conditions was carried out consecutively for 2 years (2018 and 2019 winter season). We identified, a total of 17 promising QTl which passed FDR criteria. Moreover these 17 QTL identified in the current study were mapped at different genomic locations i.e. 1B, 2A, 2B, 2D, 3A, 3B, 3D, 4B, 5B and 6B. These 17 QTLs identified in the present study might play a key role in marker-assisted breeding for developing stripe rust resistant wheat cultivars.
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Breeding science has immensely contributed to the global food security. Several varieties and hybrids in different food crops including maize have been released through conventional breeding. The ever growing population, decreasing agricultural land, lowering water table, changing climate, and other variables pose tremendous challenge to the researchers to improve the production and productivity of food crops. Drought is one of the major problems to sustain and improve the productivity of food crops including maize in tropical and subtropical production systems. With advent of novel genomics and breeding tools, the way of doing breeding has been tremendously changed in the last two decades. Drought tolerance is a combination of several component traits with a quantitative mode of inheritance. Rapid DNA and RNA sequencing tools and high-throughput SNP genotyping techniques, trait mapping, functional characterization, genomic selection, rapid generation advancement, and other tools are now available to understand the genetics of drought tolerance and to accelerate the breeding cycle. Informatics play complementary role by managing the big-data generated from the large-scale genomics and breeding experiments. Genome editing is the latest technique to alter specific genes to improve the trait expression. Integration of novel genomics, next-generation breeding, and informatics tools will accelerate the stress breeding process and increase the genetic gain under different production systems.
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Drought is one of the major threats to the maize yield especially in subtropical production systems. Understanding the genes and regulatory mechanisms of drought tolerance is important to sustain the yield. Transcription factors (TFs) play a major role in gene regulation under drought stress. In the present study, a set of 15 major TF families comprising 1,436 genes was structurally and functionally characterized. The functional annotation indicated that the genes were involved in ABA signaling, ROS scavenging, photosynthesis, stomatal regulation, and sucrose metabolism. Duplication was identified as the primary force in divergence and expansion of TF families. Phylogenetic relationship was developed for individual TF and combined TF families. Phylogenetic analysis clustered the genes into specific and mixed groups. Gene structure analysis revealed that more number of genes were intron-rich as compared to intron-less. Drought-responsive cis-regulatory elements such as ABREA, ABREB, DRE1, and DRECRTCOREAT have been identified. Expression and interaction analyses identified leaf-specific bZIP TF, GRMZM2G140355, as a potential contributor toward drought tolerance in maize. Protein-protein interaction network of 269 drought-responsive genes belonging to different TFs has been provided. The information generated on structural and functional characteristics, expression, and interaction of the drought-related TF families will be useful to decipher the drought tolerance mechanisms and to breed drought-tolerant genotypes in maize.
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Cell wall modification (CWM) promotes the formation of aerenchyma in roots under waterlogging conditions as an adaptive mechanism. Lysigenous aerenchyma formation in roots improves oxygen transfer in plants, which highlights the importance of CWM as a focal point in waterlogging stress tolerance. We investigated the structural and functional compositions of CWM genes and their expression patterns under waterlogging conditions in maize. Cell wall modification genes were identified for 3 known waterlogging-responsive cis-acting regulatory elements, namely, GC motif, anaerobic response elements, and G-box, and 2 unnamed elements. Structural motifs mapped in CWM genes were represented in genes regulating waterlogging stress-tolerant pathways, including fermentation, glycolysis, programmed cell death, and reactive oxygen species signaling. The highly aligned regions of characterized and uncharacterized CWM proteins revealed common structural domains amongst them. Membrane spanning regions present in the protein structures revealed transmembrane activity of CWM proteins in the plant cell wall. Cell wall modification proteins had interacted with ethylene-responsive pathway regulating genes (E3 ubiquitin ligases RNG finger and F-box) in a maize protein-protein interaction network. Cell wall modification genes had also coexpressed with energy metabolism, programmed cell death, and reactive oxygen species signaling, regulating genes in a single coexpression cluster. These configurations of CWM genes can be used to modify the protein expression in maize under waterlogging stress condition. Our study established the importance of CWM genes in waterlogging tolerance, and these genes can be used as candidates in introgression breeding and genome editing experiments to impart tolerance in maize hybrids.