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1.
Plant Cell Rep ; 40(1): 127-142, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33068174

RESUMO

KEY MESSAGE: The HbCAld5H1 gene cloned from Hevea brasiliensis regulates the cambial activity, xylem differentiation, syringyl-guaiacyl ratio, secondary wall structure, lignification pattern and xylan distribution in xylem fibres of transgenic tobacco plants. Molecular characterization of lignin biosynthesis gene coniferaldehyde-5-hydroxylase (CAld5H) from Hevea brasiliensis and its functional validation was performed. Both sense and antisense constructs of HbCAld5H1 gene were introduced into tobacco through Agrobacterium-mediated genetic transformation for over expression and down-regulation of this key enzyme to understand its role affecting structural and cell wall chemistry. The anatomical studies of transgenic tobacco plants revealed the increase of cambial activity leading to xylogenesis in sense lines and considerable reduction in antisense lines. The ultra-structural studies showed that the thickness of secondary wall (S2 layer) of fibre had been decreased with non-homogenous lignin distribution in antisense lines, while sense lines showed an increase in S2 layer thickness. Maule color reaction revealed that syringyl lignin distribution in the xylem elements was increased in sense and decreased in antisense lines. The immunoelectron microscopy revealed a reduction in LM 10 and LM 11 labelling in the secondary wall of antisense tobacco lines. Biochemical studies showed a radical increase in syringyl lignin in sense lines without any significant change in total lignin content, while S/G ratio decreased considerably in antisense lines. Our results suggest that CAld5H gene plays an important role in xylogenesis stages such as cambial cell division, secondary wall thickness, xylan and syringyl lignin distribution in tobacco. Therefore, CAld5H gene could be considered as a promising target for lignin modification essential for timber quality improvement in rubber.


Assuntos
Parede Celular/química , Oxigenases de Função Mista/genética , Nicotiana/genética , Proteínas de Plantas/genética , Xilema/citologia , Acroleína/análogos & derivados , Acroleína/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Lignina/genética , Lignina/metabolismo , Oxigenases de Função Mista/metabolismo , Fenótipo , Células Vegetais/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Caules de Planta/anatomia & histologia , Caules de Planta/genética , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/citologia , Nicotiana/metabolismo , Xilanos/genética , Xilanos/metabolismo , Xilema/metabolismo
2.
Physiol Mol Biol Plants ; 27(10): 2433-2446, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34566283

RESUMO

Exploding global population, rapid urbanization, salinization of soils, decreasing arable land availability, groundwater resources, and dynamic climatic conditions pose impending damage to our food security by reducing the grain quality and quantity. This issue is further compounded in arid and semi-arid regions due to the shortage of irrigation water and erratic rainfalls. Millets are gluten (a family of proteins)-free and cultivated all over the globe for human consumption, fuel, feed, and fodder. They provide nutritional security for the under- and malnourished. With the deployment of strategies like foliar spray, traditional/marker-assisted breeding, identification of candidate genes for the translocation of important minerals, and genome-editing technologies, it is now tenable to biofortify important millets. Since the bioavailability of iron and zinc has been proven in human trials, the challenge is to make such grains accessible. This review encompasses nutritional benefits, progress made, challenges being encountered, and prospects of enriching millet crops with essential minerals.

3.
Planta ; 251(4): 76, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32152761

RESUMO

MAIN CONCLUSION: There is a need to integrate conceptual framework based on the current understanding of salt stress responses with different approaches for manipulating and improving salt tolerance in crop plants. Soil salinity exerts significant constraints on global crop production, posing a serious challenge for plant breeders and biotechnologists. The classical transgenic approach for enhancing salinity tolerance in plants revolves by boosting endogenous defence mechanisms, often via a single-gene approach, and usually involves the enhanced synthesis of compatible osmolytes, antioxidants, polyamines, maintenance of hormone homeostasis, modification of transporters and/or regulatory proteins, including transcription factors and alternative splicing events. Occasionally, genetic manipulation of regulatory proteins or phytohormone levels confers salinity tolerance, but all these may cause undesired reduction in plant growth and/or yields. In this review, we present and evaluate novel and cutting-edge approaches for engineering salt tolerance in crop plants. First, we cover recent findings regarding the importance of regulatory proteins and transporters, and how they can be used to enhance salt tolerance in crop plants. We also evaluate the importance of halobiomes as a reservoir of genes that can be used for engineering salt tolerance in glycophytic crops. Additionally, the role of microRNAs as critical post-transcriptional regulators in plant adaptive responses to salt stress is reviewed and their use for engineering salt-tolerant crop plants is critically assessed. The potentials of alternative splicing mechanisms and targeted gene-editing technologies in understanding plant salt stress responses and developing salt-tolerant crop plants are also discussed.


Assuntos
Plantas Geneticamente Modificadas/genética , Salinidade , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/genética , Processamento Alternativo/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Produtos Agrícolas/genética , Edição de Genes , Genoma de Planta , Desenvolvimento Vegetal/genética , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Antiportadores de Potássio-Hidrogênio/genética , Antiportadores de Potássio-Hidrogênio/metabolismo , Locos de Características Quantitativas , Interferência de RNA
4.
Mol Biol Rep ; 47(10): 7379-7390, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32880065

RESUMO

The DnaJ/Hsp40s, are important components in the chaperone machine, and play pivotal roles in plant growth, development and stress tolerance. Sorghum, the semi-arid crop, is the drought resilient, model C4 crop. However, no reports of DnaJs have been available. Genome-wide analysis of Sorghum bicolor revealed 113 DnaJ/Hsp40 genes, classified into four groups; 8 genes in SbDnaJ-A class, 10 in SbDnaJ-B, 82 in SbDnaJ-C and 13 in SbDnaJ-D distributed unevenly on all the 10 chromosomes. Chromosomes 1 and 3 were found hot spots with 22 and 20 genes respectively. All genes displayed large number of introns, with an exception of 11 of the SbDnaJ-C which is devoid of introns. Out of 36 paralogous duplications, 7 tandem and 29 segmental duplications were noticed, indicating the major role of segmental duplications in the expansion. Analysis of digital data revealed tissue and stage-specific expressions. Transcriptional profiling of 12 selected genes representing all 4 classes revealed highly significant expression in leaf followed by root tissues. No expression was noticed in stems with an exception of SbDnaJ-C76. The SbDnaJ-A1, D1, and C subgroup genes displayed upregulation in roots, stems and leaves under cold, inferring the involvement of Hsp40s for cellular protection during cold stress. The results demonstrate that C76 and D1 are the candidate genes associated with multiple abiotic stresses. Present research furnishes valuable information about the role of sorghum DnaJs in abiotic stress response and establishes a foundation for understanding the molecular mechanisms associated with plant development and stress tolerance.


Assuntos
Regulação Viral da Expressão Gênica , Proteínas de Choque Térmico HSP40 , Proteínas de Choque Térmico HSP70 , Família Multigênica , Proteínas de Plantas , Sorghum , Estudo de Associação Genômica Ampla , Proteínas de Choque Térmico HSP40/biossíntese , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico HSP70/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Sorghum/genética , Sorghum/metabolismo
5.
Mol Biol Rep ; 46(6): 6039-6052, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31468258

RESUMO

Pearl millet is a C4 cereal crop that grows in arid and semi-arid climatic conditions with the remarkable abiotic stress tolerance. It contributed to the understanding of stress tolerance not only at the physiological level but also at the genetic level. In the present study, we functionally cloned and characterized three abiotic stress-inducible promoters namely cytoplasmic Apx1 (Ascorbate peroxidase), Dhn (Dehydrin), and Hsc70 (Heat shock cognate) from pearl millet. Sequence analysis revealed that all three promoters have several cis-acting elements specific for temporal and spatial expression. PgApx pro, PgDhn pro and PgHsc70 pro were fused with uidA gene in Gateway-based plant transformation pMDC164 vector and transferred into tobacco through leaf-disc method. While PgApx pro and PgDhn pro were active in seedling stages, PgHsc70 pro was active in stem and root tissues of the T2 transgenic tobacco plants under control conditions. Higher activity was observed under high temperature and drought, and less in salt and cold stress conditions. Further, all three promoters displayed higher GUS gene expression in the stem, moderate expression in roots, and less expression in leaves under similar conditions. While RT-qPCR data showed that PgApx pro and PgDhn pro were expressed highly in high temperature, salt and drought, PgHsc70 pro was fairly expressed during high temperature stress only. Histochemical and RT-qPCR assays showed that all three promoters are inducible under abiotic stress conditions. Thus, these promoters appear to be immediate candidates for developing abiotic stress tolerant crops as these promoter-driven transgenics confer high degree of tolerance in comparison with the wild-type (WT) plants.


Assuntos
Pennisetum/genética , Regiões Promotoras Genéticas/genética , Estresse Fisiológico/genética , Ascorbato Peroxidases/genética , Secas , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Choque Térmico/genética , Temperatura Alta , Pennisetum/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Salinidade , Tolerância ao Sal/genética , Plântula/metabolismo , Cloreto de Sódio/metabolismo , Estresse Fisiológico/fisiologia , Nicotiana/genética
6.
Physiol Mol Biol Plants ; 24(5): 809-819, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30150856

RESUMO

Plants overcome the effect of Na+ toxicity either by excluding Na+ at the plasma membrane or by sequestering them into the vacuoles. Influx of Na+ ions into the plant vacuoles is usually driven by H+ generated by vacuolar-type H+-ATPase as well as vacuolar proton pyrophosphatse (VPPase). In the present study, we have developed Bacopa monnieri transgenics via Agrobacterium tumefaciens containing the recombinant vector pCAMBIA2300-SbVPPase gene. Transformants were produced using nodal explants. Transformants were confirmed by PCR and DNA blot analysis. qPCR analysis showed higher transcript levels of SbVPPase compared to untransformed control (UC). Higher VPPase activity was recorded in transgenics compared to UC. Under 150 mM salt stress, transgenic shoots showed enhanced Na+ accumulation with better biomass production, increased glycine betaine content, and total soluble sugar levels than UC. Transgenic shoots showed 2.9-3.8-folds lower levels of malondialdehyde content indicating lesser membrane damage. Increase in antioxidant enzyme activities (1.4-3.2-folds) was observed in transgenics compared to UC. Transgenics also displayed 7.3-9.0-folds enhanced accumulation of the medicinally important compound bacoside A. Increased biomass production, accumulation of Na+, osmolytes (glycine betaine, sugars etc.), and elevated antioxidant enzyme activities indicate better osmotic adjustment in transgenics by compartmentalization of Na+ into the vacuoles under salt stress conditions. Thus, overexpression of SbVPPase in Bacopa alleviated salt stress by sequestering Na+.

7.
Plant Cell Rep ; 36(5): 773-786, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28393269

RESUMO

KEY MESSAGE: SbAP37 transcription factor contributes to a combination of abiotic stresses when applied simultaneously in rice. It modulates a plethora of proteins that might regulate the downstream pathways to impart salt stress tolerance. APETALA type of transcription factor was isolated from Sorghum bicolor (SbAP37), overexpressed in rice using a salt inducible abscisic acid 2 (ABA2) promoter through Agrobacterium tumefaciens following in planta method. Transgenics were confirmed by PCR amplification of SbAP37, hygromycin phosphotransferase (hptII) marker and ABA2 promoter and DNA blot analysis. Plants were exposed to 150 mM NaCl coupled with high day/night 36 ± 2/25 ± 2 °C temperatures and also drought stress by withholding water for 1-week separately at the booting stage. SbAP37 expression was 2.8- to 4.7-folds higher in transgenic leaf under salt, but 1.8- to 3.3-folds higher in roots under drought stress. Native gene expression analysis showed that it is expressed more in stem than in roots and leaves under 150 mM NaCl and 6% PEG stress. In the present study, proteomic analysis of transgenics exposed to 150 mM NaCl coupled with elevated temperatures was taken up using quadrupole time-of-flight (Q-TOF) mass spectrometry (MS). The leaf proteome revealed 11 down regulated, 26 upregulated, 101 common (shared), 193 newly synthesized proteins in transgenics besides 368 proteins in untransformed plants. Some of these protein sets appeared different and unique to combined stresses. Our results suggest that the SbAP37 has the potential to improve combined stress tolerance without causing undesirable phenotypic characters when used under the influence of ABA2 promoter.


Assuntos
Oryza/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Folhas de Planta/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Proteômica , Tolerância ao Sal/genética , Tolerância ao Sal/fisiologia , Temperatura
8.
Biometals ; 29(2): 187-210, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26796895

RESUMO

Aluminum (Al) stress is one of the serious limiting factors in plant productivity in acidic soils, which constitute about 50 % of the world's potentially arable lands and causes anywhere between 25 and 80 % of yield losses depending upon the species. The mechanism of Al toxicity and tolerance has been examined in plants, which is vital for crop improvement and enhanced food production in the future. Two mechanisms that facilitate Al tolerance in plants are Al exclusion from the roots and the ability to tolerate Al in the symplast or both. Although efforts have been made to unravel Al-resistant factors, many aspects remain unclear. Certain gene families such as MATE, ALMT, ASR, and ABC transporters have been implicated in some plants for resistance to Al which would enhance the opportunities for creating crop plants suitable to grow in acidic soils. Though QTLs have been identified related to Al-tolerance, no crop plant that is tolerant to Al has been evolved so far using breeding or molecular approaches. The remarkable changes that plants experience at the physiological, biochemical and molecular level under Al stress, the vast array of genes involved in Al toxicity-tolerance, the underlying signaling events and the holistic image of the molecular regulation, and the possibility of creating transgenics for Al tolerance are discussed in this review.


Assuntos
Alumínio/farmacologia , Produtos Agrícolas/crescimento & desenvolvimento , Poluentes do Solo/farmacologia , Solo/química , Adaptação Fisiológica , Produtos Agrícolas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Humanos , Concentração de Íons de Hidrogênio , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mapas de Interação de Proteínas
9.
Indian J Exp Biol ; 52(11): 1112-21, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25434107

RESUMO

Various parameters including explant-type, medium compositions, use of phytohormones and additives were optimized for direct and indirect regeneration of E. ochreata, a medicinal orchid under threat. Protocorm-like-bodies (PLBs) proved to be the best explants for shoot initiation, proliferation and callus induction. Murashige and Skoog's (MS) medium containing 2.5 mg L(-1) 6-benzylaminopurine (BAP), 1.0 mg L(-1) kinetin (Kin) and additives (adenine sulfate, arginine, citric acid, 30 mg L(-1) each and 50 mg L(-1) ascorbic acid) was optimal for shoot multiplication (12.1 shoots and 7.1 PLBs per explant with synchronized growth), which also produced callus. Shoot number was further increased with three successive subcultures on same media and approximately 40 shoots per explant were achieved after 3 cycles of 30 days each. Additives and casein hydrolysate (CH) showed advantageous effects on indirect shoot regeneration via protocorm-derived callus. Optimum indirect regeneration was achieved on MS containing additives, 500 mg L(-1) CH, 2.5 mg L(-1) BAP and 1.0 mg L(-1) Kin with 30 PLBs and 6 shoots per callus mass (approximately 5 mm size). The shoots were rooted (70% frequency) on one by fourth-MS medium containing 2.0 mg L(-1) indole-3-butyric acid, 200 mg L(-1) activated charcoal and additives. The rooted plantlets were hardened and transferred to greenhouse with 63% survival rate. Flow-cytometry based DNA content analysis revealed that the ploidy levels were maintained in in vitro regenerated plants. This is the first report for in vitro plant regeneration in E. ochreata.


Assuntos
Orchidaceae/fisiologia , Técnicas de Cultura de Tecidos , Ácido Ascórbico/farmacologia , Caseínas/farmacologia , Cromossomos de Plantas , Ácido Cítrico/farmacologia , Meios de Cultura/farmacologia , Citocininas/farmacologia , Ácidos Indolacéticos/farmacologia , Orchidaceae/genética , Orchidaceae/crescimento & desenvolvimento , Organoides/efeitos dos fármacos , Organoides/fisiologia , Células Vegetais/efeitos dos fármacos , Células Vegetais/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Plantas Medicinais/genética , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/fisiologia , Ploidias , Regeneração , Rizoma/efeitos dos fármacos , Rizoma/crescimento & desenvolvimento
10.
Ecotoxicology ; 21(1): 202-12, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21879358

RESUMO

In the present study, 44 arsenic-resistant bacteria were isolated through serial dilutions on agar plate with concentrations ≥0.05 mM of sodium arsenite and ≥10 mM of sodium arsenate from Mandovi and Zuari--estuarine water systems. The ars genotype characterization in 36 bacterial isolates (resistant to 100 mM of sodium arsenate) revealed that only 17 isolates harboured the arsA (ATPase), B (arsenite permease) and C (arsenate reductase) genes on the plasmid DNA. The arsA, B and C genes were individually detected using PCR in 16, 9 and 13 bacterial isolates respectively. Molecular identification of the 17 isolates bearing the ars genotype was carried using 16S rDNA sequencing. A 1300 bp full length arsB gene encoding arsenite efflux pump and a 409 bp fragment of arsC gene coding for arsenate reductase were isolated from the genera Halomonas and Acinetobacter. Phylogenetic analysis of arsB and arsC genes indicated their close genetic relationship with plasmid borne ars genes of E. coli and arsenate reductase of plant origin. The putative arsenate reductase gene isolated from Acinetobacter species complemented arsenate resistance in E. coli WC3110 and JM109 validating its function. This study dealing with isolation of native arsenic-resistant bacteria and characterization of their ars genes might be useful to develop efficient arsenic detoxification strategies for arsenic contaminated aquifers.


Assuntos
Arsênio/metabolismo , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Genes Bacterianos , Arseniatos/análise , Arseniatos/metabolismo , Arsenitos/análise , Arsenitos/metabolismo , DNA Bacteriano/genética , Recuperação e Remediação Ambiental/métodos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Deleção de Genes , Genótipo , Bombas de Íon/genética , Bombas de Íon/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Compostos de Sódio/análise , Compostos de Sódio/metabolismo
11.
Indian J Exp Biol ; 50(7): 484-90, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22822528

RESUMO

Leaves of Withania somnifera contained more withaferin A and withanolide A than roots indicating that these compounds mainly accumulate in leaves. With an increase in age of the plant, withaferin A was enhanced with a corresponding decrease in withanolide A. Hairy root cultures were induced from leaf explants using Agrobacterium rhizogenes and the transgenic nature of hairy roots was confirmed by partial isolation and sequencing of rolB gene, which could not be amplified in untransformed plant parts. In hairy roots, withaferin A accumulated at 2, 3 and 4% but not at 6% sucrose, the highest amount being 1733 microg/g dry weight at 4% level. High and equal amounts of withaferin A and withanolide A accumulated (890 and 886 microg/g dry tissue respectively) only at 3% sucrose. Increasing concentrations of glucose enhanced withaferin A and it peaked at 5% level (3866 microg/g dry tissue). This amount is 2842 and 34% higher compared to untransformed roots and leaves (collected from 210-day-old plants) respectively. Withanolide A was detected at 5% glucose but not at other concentrations. While chitosan and nitric oxide increased withaferin A, jasmonic acid decreased it. Acetyl salicylic acid stimulated accumulation of both withaferin A and withanolide A at higher concentrations. Triadimefon, a fungicide, enhanced withaferin A by 1626 and 3061% (not detected earlier) compared to hairy and intact roots respectively.


Assuntos
Carboidratos/farmacologia , Raízes de Plantas/metabolismo , Withania/metabolismo , Vitanolídeos/metabolismo , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Primers do DNA , Reação em Cadeia da Polimerase , Withania/genética
12.
Front Plant Sci ; 13: 867531, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795343

RESUMO

Proline is a proteinogenic amino acid synthesized from glutamate and ornithine. Pyrroline-5-carboxylate synthetase and pyrroline-5-carboxylate reductase are the two key enzymes involved in proline synthesis from glutamate. On the other hand, ornithine-δ-aminotransferase converts ornithine to pyrroline 5-carboxylate (P5C), an intermediate in the synthesis of proline as well as glutamate. Both proline dehydrogenase and P5C dehydrogenase convert proline back to glutamate. Proline accumulation is widespread in response to environmental challenges such as high temperatures, and it is known to defend plants against unpropitious situations promoting plant growth and flowering. While proline accumulation is positively correlated with heat stress tolerance in some crops, it has detrimental consequences in others. Although it has been established that proline is a key osmolyte, its exact physiological function during heat stress and plant ontogeny remains unknown. Emerging evidence pointed out its role as an overriding molecule in alleviating high temperature stress (HTS) by quenching singlet oxygen and superoxide radicals. Proline cycle acts as a shuttle and the redox couple (NAD+/NADH, NADP+/NADPH) appears to be highly crucial for energy transfer among different cellular compartments during plant development, exposure to HTS conditions and also during the recovery of stress. In this review, the progress made in recent years regarding its involvement in heat stress tolerance is highlighted.

13.
Front Plant Sci ; 13: 965530, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119582

RESUMO

Potassium (K+) is the most abundant cation that plays a crucial role in various cellular processes in plants. Plants have developed an efficient mechanism for the acquisition of K+ when grown in K+ deficient or saline soils. A total of 47 K+ transport gene homologs (27 HAKs, 4 HKTs, 2 KEAs, 9 AKTs, 2 KATs, 2 TPCs, and 1 VDPC) have been identified in Sorghum bicolor. Of 47 homologs, 33 were identified as K+ transporters and the remaining 14 as K+ channels. Chromosome 2 has been found as the hotspot of K+ transporters with 9 genes. Phylogenetic analysis revealed the conservation of sorghum K+ transport genes akin to Oryza sativa. Analysis of regulatory elements indicates the key roles that K+ transport genes play under different biotic and abiotic stress conditions. Digital expression data of different developmental stages disclosed that expressions were higher in milk, flowering, and tillering stages. Expression levels of the genes SbHAK27 and SbKEA2 were higher during milk, SbHAK17, SbHAK11, SbHAK18, and SbHAK7 during flowering, SbHAK18, SbHAK10, and 23 other gene expressions were elevated during tillering inferring the important role that K+ transport genes play during plant growth and development. Differential transcript expression was observed in different tissues like root, stem, and leaf under abiotic stresses such as salt, drought, heat, and cold stresses. Collectively, the in-depth genome-wide analysis and differential transcript profiling of K+ transport genes elucidate their role in ion homeostasis and stress tolerance mechanisms.

14.
Genes (Basel) ; 13(12)2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36553647

RESUMO

Delayed cancer detection is one of the common causes of poor prognosis in the case of many cancers, including cancers of the oral cavity. Despite the improvement and development of new and efficient gene therapy treatments, very little has been carried out to algorithmically assess the impedance of these carcinomas. In this work, from attributes or NCBI's oral cancer datasets, viz. (i) name, (ii) gene(s), (iii) protein change, (iv) condition(s), clinical significance (last reviewed). We sought to train the number of instances emerging from them. Further, we attempt to annotate viable attributes in oral cancer gene datasets for the identification of gingivobuccal cancer (GBC). We further apply supervised and unsupervised machine learning methods to the gene datasets, revealing key candidate attributes for GBC prognosis. Our work highlights the importance of automated identification of key genes responsible for GBC that could perhaps be easily replicated in other forms of oral cancer detection.


Assuntos
Heurística , Neoplasias Bucais , Humanos , Aprendizado de Máquina , Prognóstico , Oncogenes , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/genética
15.
Plant Cell Rep ; 30(12): 2215-31, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21847621

RESUMO

cDNA and genomic clones of cinnamoyl CoA reductase measuring 1011 and 2992 bp were isolated from a leguminous pulpwood tree Leucaena leucocephala, named as LlCCR. The cDNA exhibited 80-85% homology both at the nucleotide and amino acid levels with other known sequences. The genomic sequence contained five exons and four introns. Sense and antisense constructs of LlCCR were introduced in tobacco plants to up and down-regulate this key enzyme of lignification. The primary transformants showed a good correlation between CCR transcript levels and its activity. Most of the CCR down-regulated lines displayed stunted growth and development, wrinkled leaves and delayed senescence. These lines accumulated unusual phenolics like ferulic and sinapic acids in cell wall. Histochemical staining suggested reduction in aldehyde units and increased syringyl over guaiacyl (S/G) ratio of lignin. Anatomical studies showed thin walled, elongated xylem fibres, collapsed vessels with drastic reduction of secondary xylem. The transmission electron microscopic studies revealed modification of ultrastructure and topochemical distribution of wall polysaccharides and lignin in the xylem fibres. CCR down-regulated lines showed increased thickness of secondary wall layers and poor lignification of S2 and S3 wall layers. The severely down-regulated line AS17 exhibited 24.7% reduction of Klason lignin with an increase of 15% holocellulose content. Contrarily, the CCR up-regulated lines exhibited robust growth, development and significant increase in lignin content. The altered lignin profiles observed in transgenic tobacco lines support a role for CCR down-regulation in improving wood properties of L. leucocephala exclusively used in the pulp and paper industry of India.


Assuntos
Aldeído Oxirredutases/metabolismo , Fabaceae/enzimologia , Lignina/análise , Fenóis/análise , Proteínas de Plantas/metabolismo , Aldeído Oxirredutases/genética , Celulose/análise , Celulose/metabolismo , DNA Complementar/genética , DNA de Plantas/genética , Regulação para Baixo , Fabaceae/genética , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Microscopia Eletrônica de Transmissão , Fenóis/metabolismo , Fenótipo , Proteínas de Plantas/genética , Caules de Planta/anatomia & histologia , Caules de Planta/ultraestrutura , Plantas Geneticamente Modificadas/genética , Nicotiana/química , Nicotiana/genética , Transformação Genética
16.
Int J Biol Macromol ; 142: 822-834, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622710

RESUMO

The small heat shock proteins (sHsps/Hsp20s) are the molecular chaperones that maintain proper folding, trafficking and disaggregation of proteins under diverse abiotic stress conditions. In the present investigation, a genome-wide scan revealed the presence of a total of 47 sHsps in Sorghum bicolor (SbsHsps), distributed across 10 subfamilies, the major subfamily being P (plastid) group with 17 genes. Chromosomes 1 and 3 appear as the hot spot regions for SbsHsps, and majority of them were found acidic, hydrophilic, unstable and intron less. Interestingly, promoter analysis indicated that they are associated with both biotic and abiotic stresses, as well as plant development. Sorghum sHsps exhibited 15 paralogous and 20 orthologous duplications. Expression analysis of 15 genes selected from different subfamilies showed high transcript levels in roots and leaves implying that they are likely to participate in the developmental processes. SbsHsp genes were highly induced by diverse abiotic stresses inferring their critical role in mediating the environmental stress responses. Gene expression data revealed that SbsHsp-02 is a candidate gene expressed in all the tissues under varied stress conditions tested. Our results contribute to the understanding of the complexity of SbsHsp genes and help to analyse them further for functional validation.


Assuntos
Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Choque Térmico Pequenas/genética , Proteínas de Plantas/genética , Sorghum/genética , Estresse Fisiológico/fisiologia , Sequência de Bases , Simulação por Computador , Perfilação da Expressão Gênica , Genoma de Planta , Proteínas de Choque Térmico Pequenas/metabolismo , Família Multigênica/genética , Filogenia , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Transcriptoma
17.
PLoS One ; 14(1): e0209980, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30650107

RESUMO

Late embryogenesis abundant (LEA) proteins, the space fillers or molecular shields, are the hydrophilic protective proteins which play an important role during plant development and abiotic stress. The systematic survey and characterization revealed a total of 68 LEA genes, belonging to 8 families in Sorghum bicolor. The LEA-2, a typical hydrophobic family is the most abundant family. All of them are evenly distributed on all 10 chromosomes and chromosomes 1, 2, and 3 appear to be the hot spots. Majority of the S. bicolor LEA (SbLEA) genes are intron less or have fewer introns. A total of 22 paralogous events were observed and majority of them appear to be segmental duplications. Segmental duplication played an important role in SbLEA-2 family expansion. A total of 12 orthologs were observed with Arabidopsis and 13 with Oryza sativa. Majority of them are basic in nature, and targeted by chloroplast subcellular localization. Fifteen miRNAs targeted to 25 SbLEAs appear to participate in development, as well as in abiotic stress tolerance. Promoter analysis revealed the presence of abiotic stress-responsive DRE, MYB, MYC, and GT1, biotic stress-responsive W-Box, hormone-responsive ABA, ERE, and TGA, and development-responsive SKn cis-elements. This reveals that LEA proteins play a vital role during stress tolerance and developmental processes. Using microarray data, 65 SbLEA genes were analyzed in different tissues (roots, pith, rind, internode, shoot, and leaf) which show clear tissue specific expression. qRT-PCR analysis of 23 SbLEA genes revealed their abundant expression in various tissues like roots, stems and leaves. Higher expression was noticed in stems compared to roots and leaves. Majority of the SbLEA family members were up-regulated at least in one tissue under different stress conditions. The SbLEA3-2 is the regulator, which showed abundant expression under diverse stress conditions. Present study provides new insights into the formation of LEAs in S. bicolor and to understand their role in developmental processes under stress conditions, which may be a valuable source for future research.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Sorghum/genética , Estresse Fisiológico , Sequência de Aminoácidos , Mapeamento Cromossômico , Regulação da Expressão Gênica no Desenvolvimento , Genoma de Planta , MicroRNAs/genética , Filogenia , Proteínas de Plantas/análise , Sorghum/química , Sorghum/crescimento & desenvolvimento , Sorghum/fisiologia , Transcriptoma
18.
PLoS One ; 14(9): e0222203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31536532

RESUMO

Members of the plant Heme Activator Protein (HAP) or NUCLEAR FACTOR Y (NF-Y) are trimeric transcription factor complexes composed of the NF-YA, NF-YB and NF-YC subfamilies. They bind to the CCAAT box in the promoter regions of the target genes and regulate gene expressions. Plant NF-Ys were reported to be involved in adaptation to several abiotic stresses as well as in development. In silico analysis of Sorghum bicolor genome resulted in the identification of a total of 42 NF-Y genes, among which 8 code for the SbNF-YA, 19 for SbNF-YB and 15 for the SbNF-YC subunits. Analysis was also performed to characterize gene structures, chromosomal distribution, duplication status, protein subcellular localizations, conserved motifs, ancestral protein sequences, miRNAs and phylogenetic tree construction. Phylogenetic relationships and ortholog predictions displayed that sorghum has additional NF-YB genes with unknown functions in comparison with Arabidopsis. Analysis of promoters revealed that they harbour many stress-related cis-elements like ABRE and HSE, but surprisingly, DRE and MYB elements were not detected in any of the subfamilies. SbNF-YA1, 2, and 6 were found upregulated under 200 mM salt and 200 mM mannitol stresses. While NF-YA7 appeared associated with high temperature (40°C) stress, NF-YA8 was triggered by both cold (4°C) and high temperature stresses. Among NF-YB genes, 7, 12, 15, and 16 were induced under multiple stress conditions such as salt, mannitol, ABA, cold and high temperatures. Likewise, NF-YC 6, 11, 12, 14, and 15 were enhanced significantly in a tissue specific manner under multiple abiotic stress conditions. Majority of the mannitol (drought)-inducible genes were also induced by salt, high temperature stresses and ABA. Few of the high temperature stress-induced genes are also induced by cold stress (NF-YA2, 4, 6, 8, NF-YB2, 7, 10, 11, 12, 14, 16, 17, NF-YC4, 6, 12, and 13) thus suggesting a cross talk among them. This work paves the way for investigating the roles of diverse sorghum NF-Y proteins during abiotic stress responses and provides an insight into the evolution of diverse NF-Y members.


Assuntos
Fator de Ligação a CCAAT/genética , Genes de Plantas/genética , Proteínas de Plantas/genética , Sorghum/genética , Mapeamento Cromossômico , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
19.
Genes (Basel) ; 9(5)2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29751546

RESUMO

Na⁺ transporters play an important role during salt stress and development. The present study is aimed at genome-wide identification, in silico analysis of sodium-proton antiporter (NHX) and sodium-proton exchanger (NHE)-type transporters in Sorghum bicolor and their expression patterns under varied abiotic stress conditions. In Sorghum, seven NHX and nine NHE homologs were identified. Amiloride (a known inhibitor of Na⁺/H⁺ exchanger activity) binding motif was noticed in both types of the transporters. Chromosome 2 was found to be a hotspot region with five sodium transporters. Phylogenetic analysis inferred six ortholog and three paralog groups. To gain an insight into functional divergence of SbNHX/NHE transporters, real-time gene expression was performed under salt, drought, heat, and cold stresses in embryo, root, stem, and leaf tissues. Expression patterns revealed that both SbNHXs and SbNHEs are responsive either to single or multiple abiotic stresses. The predicted protein⁻protein interaction networks revealed that only SbNHX7 is involved in the calcineurin B-like proteins (CBL)- CBL interacting protein kinases (CIPK) pathway. The study provides insights into the functional divergence of SbNHX/NHE transporter genes with tissue specific expressions in Sorghum under different abiotic stress conditions.

20.
Gene ; 388(1-2): 1-13, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17134853

RESUMO

Environmental constraints that include abiotic stress factors such as salt, drought, cold and extreme temperatures severely limit crop productivity. Improvement of crop plants with traits that confer tolerance to these stresses was practiced using traditional and modern breeding methods. Molecular breeding and genetic engineering contributed substantially to our understanding of the complexity of stress response. Mechanisms that operate signal perception, transduction and downstream regulatory factors are now being examined and an understanding of cellular pathways involved in abiotic stress responses provide valuable information on such responses. This review presents genomic-assisted methods which have helped to reveal complex regulatory networks controlling abiotic stress tolerance mechanisms by high-throughput expression profiling and gene inactivation techniques. Further, an account of stress-inducible regulatory genes which have been transferred into crop plants to enhance stress tolerance is discussed as possible modes of integrating information gained from functional genomics into knowledge-based breeding programs. In addition, we envision an integrative genomic and breeding approach to reveal developmental programs that enhance yield stability and improve grain quality under unfavorable environmental conditions of abiotic stresses.


Assuntos
Perfilação da Expressão Gênica , Genômica/métodos , Plantas/genética , Adaptação Fisiológica/genética , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Desenvolvimento Vegetal , Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Cloreto de Sódio/farmacologia , Temperatura , Água/farmacologia
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