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Verma NV, Tiwari BS, Pandya A. Paper disc interfaced Prussian blue nanocube modified immunodevice for electrochemical detection of diverse biomarker at point of care. Bioelectrochemistry 2023; 150:108346. [PMID: 36493675 DOI: 10.1016/j.bioelechem.2022.108346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022]
Abstract
The detection of specific biomarkers is used in various phases of the diagnosis of plant and human diseases, from prognosis to monitoring. Herein, we report a Prussian blue nanocube-modified immunodevice interfaced with a paper disc for the detection of plant biomarkers via streptavidin-biotin recognition. The detection ability of the immunodevice was assessed using Potato virus X as a model biomarker and analyzed using cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. The immunodevice displayed excellent performance for Potato virus X detection with a detection limit of 0.92 nM (3S/N). The selectivity of the fabricated Potato virus X immunodevice was investigated using closely associated antigens, such as potato aucuba mosaic virus, Potato virus Y, and Potato virus A. The Potato virus X immunodevice exhibited ∼ 90 % recovery in spiked complex plant samples with a relative error of ∼ 9 %. Furthermore, the immunodevice was used to screen for Potato virus X in 10 samples from potato tubers and leaves. The paper-disc-interfaced immunodevice was also evaluated by detecting other biomarkers, such as potato aucuba mosaic virus in plant diseases and C-reactive protein in human ones. This immunodevice may allow the on-site monitoring of diverse biomarkers by simplifying the current point of care diagnostic tools.
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Affiliation(s)
- Nidhi Vijay Verma
- Department of Biotechnology and Bioengineering, Institute of Advanced Research, Gandhinagar, Gujarat 382426, India
| | - Budhi Sagar Tiwari
- Department of Biotechnology and Bioengineering, Institute of Advanced Research, Gandhinagar, Gujarat 382426, India
| | - Alok Pandya
- Department of Biotechnology and Bioengineering, Institute of Advanced Research, Gandhinagar, Gujarat 382426, India.
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Mishra S, Raval M, Kachhawaha AS, Tiwari BS, Tiwari AK. Aging: Epigenetic modifications. Progress in Molecular Biology and Translational Science 2023; 197:171-209. [PMID: 37019592 DOI: 10.1016/bs.pmbts.2023.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
Aging is one of the most complex and irreversible health conditions characterized by continuous decline in physical/mental activities that eventually poses an increased risk of several diseases and ultimately death. These conditions cannot be ignored by anyone but there are evidences that suggest that exercise, healthy diet and good routines may delay the Aging process significantly. Several studies have demonstrated that Epigenetics plays a key role in Aging and Aging-associated diseases through methylation of DNA, histone modification and non-coding RNA (ncRNA). Comprehension and relevant alterations in these epigenetic modifications can lead to new therapeutic avenues of age-delaying contrivances. These processes affect gene transcription, DNA replication and DNA repair, comprehending epigenetics as a key factor in understanding Aging and developing new avenues for delaying Aging, clinical advancements in ameliorating aging-related diseases and rejuvenating health. In the present article, we have described and advocated the epigenetic role in Aging and associated diseases.
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Tomar V, Singh D, Dhillon GS, Chung YS, Poland J, Singh RP, Joshi AK, Gautam Y, Tiwari BS, Kumar U. Increased Predictive Accuracy of Multi-Environment Genomic Prediction Model for Yield and Related Traits in Spring Wheat ( Triticum aestivum L.). Front Plant Sci 2021; 12:720123. [PMID: 34691100 PMCID: PMC8531512 DOI: 10.3389/fpls.2021.720123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 09/03/2021] [Indexed: 06/13/2023]
Abstract
Genomic selection (GS) has the potential to improve the selection gain for complex traits in crop breeding programs from resource-poor countries. The GS model performance in multi-environment (ME) trials was assessed for 141 advanced breeding lines under four field environments via cross-predictions. We compared prediction accuracy (PA) of two GS models with or without accounting for the environmental variation on four quantitative traits of significant importance, i.e., grain yield (GRYLD), thousand-grain weight, days to heading, and days to maturity, under North and Central Indian conditions. For each trait, we generated PA using the following two different ME cross-validation (CV) schemes representing actual breeding scenarios: (1) predicting untested lines in tested environments through the ME model (ME_CV1) and (2) predicting tested lines in untested environments through the ME model (ME_CV2). The ME predictions were compared with the baseline single-environment (SE) GS model (SE_CV1) representing a breeding scenario, where relationships and interactions are not leveraged across environments. Our results suggested that the ME models provide a clear advantage over SE models in terms of robust trait predictions. Both ME models provided 2-3 times higher prediction accuracies for all four traits across the four tested environments, highlighting the importance of accounting environmental variance in GS models. While the improvement in PA from SE to ME models was significant, the CV1 and CV2 schemes did not show any clear differences within ME, indicating the ME model was able to predict the untested environments and lines equally well. Overall, our results provide an important insight into the impact of environmental variation on GS in smaller breeding programs where these programs can potentially increase the rate of genetic gain by leveraging the ME wheat breeding trials.
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Affiliation(s)
- Vipin Tomar
- Borlaug Institute for South Asia, Ludhiana, India
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, India
- International Maize and Wheat Improvement Center, New Delhi, India
| | - Daljit Singh
- Department of Plant Pathology, Kansas State University, Manhattan, KS, United States
| | - Guriqbal Singh Dhillon
- Department of Biotechnology, Thapar Institute of Engineering & Technology, Patiala, India
| | - Yong Suk Chung
- Department of Plant Resources and Environment, Jeju National University, Jeju-si, South Korea
| | - Jesse Poland
- Department of Plant Pathology, Kansas State University, Manhattan, KS, United States
| | - Ravi Prakash Singh
- Global Wheat Program, International Maize and Wheat Improvement Center, Texcoco, Mexico
| | - Arun Kumar Joshi
- Borlaug Institute for South Asia, Ludhiana, India
- International Maize and Wheat Improvement Center, New Delhi, India
- Global Wheat Program, International Maize and Wheat Improvement Center, Texcoco, Mexico
| | | | - Budhi Sagar Tiwari
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, India
| | - Uttam Kumar
- Borlaug Institute for South Asia, Ludhiana, India
- International Maize and Wheat Improvement Center, New Delhi, India
- Global Wheat Program, International Maize and Wheat Improvement Center, Texcoco, Mexico
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Bhatt M, Pandey SS, Tiwari AK, Tiwari BS. Plastid-mediated singlet oxygen in regulated cell death. Plant Biol (Stuttg) 2021; 23:686-694. [PMID: 33768665 DOI: 10.1111/plb.13260] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 03/09/2021] [Indexed: 06/12/2023]
Abstract
Reactive oxygen species (ROS) generation within a cell is a natural process of specific subcellular components involved in redox reactions. Within a plant cell, chloroplasts are one of the major sources of ROS generation. Plastid-generated ROS molecules include singlet oxygen (1 O2 ), superoxide radical (O2 - ), hydroxyl radical (OH• ) and hydrogen peroxide (H2 O2 ), which are produced mainly during photochemical reactions of photosynthesis and chlorophyll biosynthetic process. Under normal growth and developmental, generated ROS molecules act as a secondary messenger controlling several metabolic reactions; however, perturbed environmental conditions lead to multi-fold amplification of cellular ROS that eventually kill the target cell. To maintain homeostasis between production and scavenging of ROS, the cell has instituted several enzymatic and non-enzymatic antioxidant machineries to maintain ROS at a physiological level. Among chloroplastic ROS molecules, excess generation of singlet oxygen (1 O2 ) is highly deleterious to the cell metabolic functions and survival. Interestingly, within cellular antioxidant machinery, enzymes involved in detoxification of 1 O2 are lacking. Recent studies suggest that under optimal concentrations, 1 O2 acts as a signalling molecule and drives the cell to either the acclimation pathway or regulated cell death (RCD). Stress-induced RCD is a survival mechanism for the whole plant, while the involvement of chloroplasts and chloroplast-localized molecules that execute RCD are not well understood. In this review, we advocate for participation of chloroplasts-generated 1 O2 in signalling and RCD in plants.
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Affiliation(s)
- M Bhatt
- Institute of Advanced Research, Gandhinagar, Gujrat, India
| | - S S Pandey
- Biotechnology Division, CSIR-Institute of Himalayan Bioresource Technology, Palampur, H.P., India
| | - A K Tiwari
- Institute of Advanced Research, Gandhinagar, Gujrat, India
| | - B S Tiwari
- Institute of Advanced Research, Gandhinagar, Gujrat, India
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Tomar V, Dhillon GS, Singh D, Singh RP, Poland J, Joshi AK, Tiwari BS, Kumar U. Elucidating SNP-based genetic diversity and population structure of advanced breeding lines of bread wheat ( Triticum aestivum L .). PeerJ 2021; 9:e11593. [PMID: 34221720 PMCID: PMC8231316 DOI: 10.7717/peerj.11593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 05/20/2021] [Indexed: 11/20/2022] Open
Abstract
Genetic diversity and population structure information are crucial for enhancing traits of interest and the development of superlative varieties for commercialization. The present study elucidated the population structure and genetic diversity of 141 advanced wheat breeding lines using single nucleotide polymorphism markers. A total of 14,563 high-quality identified genotyping-by-sequencing (GBS) markers were distributed covering 13.9 GB wheat genome, with a minimum of 1,026 SNPs on the homoeologous group four and a maximum of 2,838 SNPs on group seven. The average minor allele frequency was found 0.233, although the average polymorphism information content (PIC) and heterozygosity were 0.201 and 0.015, respectively. Principal component analyses (PCA) and population structure identified two major groups (sub-populations) based on SNPs information. The results indicated a substantial gene flow/exchange with many migrants (Nm = 86.428) and a considerable genetic diversity (number of different alleles, Na = 1.977; the number of effective alleles, Ne = 1.519; and Shannon's information index, I = 0.477) within the population, illustrating a good source for wheat improvement. The average PIC of 0.201 demonstrates moderate genetic diversity of the present evaluated advanced breeding panel. Analysis of molecular variance (AMOVA) detected 1% and 99% variance between and within subgroups. It is indicative of excessive gene traffic (less genetic differentiation) among the populations. These conclusions deliver important information with the potential to contribute new beneficial alleles using genome-wide association studies (GWAS) and marker-assisted selection to enhance genetic gain in South Asian wheat breeding programs.
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Affiliation(s)
- Vipin Tomar
- Borlaug Institute for South Asia, New Delhi, Delhi, India.,Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, Gandhinagar, Gujarat, India.,International Maize and Wheat Improvement Centre, New Delhi, Delhi, India
| | - Guriqbal Singh Dhillon
- Department of Biotechnology, Thapar Institute of Engineering and Technology, Patiala, Punjab, India
| | - Daljit Singh
- The Climate Corporation, Bayer Crop Science, Creve Coeur, MO, USA
| | - Ravi Prakash Singh
- Global Wheat Program, International Maize and Wheat Improvement Centre, Texcoco, Mexico
| | - Jesse Poland
- Department of Plant Pathology, Kansas State University, Manhattan, KS, United States of America
| | - Arun Kumar Joshi
- Borlaug Institute for South Asia, New Delhi, Delhi, India.,International Maize and Wheat Improvement Centre, New Delhi, Delhi, India.,Global Wheat Program, International Maize and Wheat Improvement Centre, Texcoco, Mexico
| | - Budhi Sagar Tiwari
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, Gandhinagar, Gujarat, India
| | - Uttam Kumar
- Borlaug Institute for South Asia, New Delhi, Delhi, India.,International Maize and Wheat Improvement Centre, New Delhi, Delhi, India.,Global Wheat Program, International Maize and Wheat Improvement Centre, Texcoco, Mexico
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Tomar V, Singh D, Dhillon GS, Singh RP, Poland J, Joshi AK, Singh PK, Bhati PK, Kumar S, Rahman M, Tiwari BS, Kumar U. New QTLs for Spot Blotch Disease Resistance in Wheat ( Triticum aestivum L.) Using Genome-Wide Association Mapping. Front Genet 2021; 11:613217. [PMID: 33519916 PMCID: PMC7841440 DOI: 10.3389/fgene.2020.613217] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/10/2020] [Indexed: 11/13/2022] Open
Abstract
Spot blotch disease caused by Bipolaris sorokiniana is a major constraint for wheat production in tropics and subtropics. The introgression of spot blotch resistance alleles to the disease susceptible lines is critical to securing the wheat production in these regions. Although genome-wide association studies (GWASs) for spot blotch were attempted earlier, the present study focused on identifying new quantitative trait loci (QTLs) for spot blotch under natural disease pressure in diverse field conditions. A total of 139 advanced spring wheat lines were evaluated in three environments (three years and two locations) in India and Bangladesh. The GWAS using 14,063 polymorphic genotyping-by-sequencing (GBS) markers identified eight QTLs associated with spot blotch disease resistance belonging to eight chromosomes across the wheat genome. Here, we report the identified marker–trait associations (MTAs), along with the allele effects associated with the disease. The functional annotation of the significant markers identified NBS-LRR, MADS-box transcription factor, and 34 other plant-related protein families across multiple chromosomal regions. The results indicate four promising new QTLs on chromosomes 1A (497.2 Mb), 1D (89.84 Mb), 2B (421.92 Mb), and 6D (6.84 Mb) associated with several disease resistance protein families. These results provide insights into new genomic regions associated with spot blotch disease, and with additional validation, could be utilized in disease resistance breeding efforts in wheat development.
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Affiliation(s)
- Vipin Tomar
- Borlaug Institute for South Asia, Ludhiana, India.,Institute of Advanced Research, Gandhinagar, Gujarat, India
| | - Daljit Singh
- The Climate Corporation, Bayer Crop Science, Creve Coeur, MO, United States
| | - Guriqbal Singh Dhillon
- Department of Biotechnology, Thapar Institute of Engineering and Technology, Patiala, India
| | - Ravi Prakash Singh
- Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | - Jesse Poland
- Department of Plant Pathology, Kansas State University, Manhattan, KS, United States
| | - Arun Kumar Joshi
- Borlaug Institute for South Asia, Ludhiana, India.,International Maize and Wheat Improvement Centre, New Delhi, India
| | - Pawan Kumar Singh
- Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | | | - Suneel Kumar
- Borlaug Institute for South Asia, Ludhiana, India
| | - Mokhlesur Rahman
- Wheat Research Center, Regional Agricultural Research Station, Bangladesh Agricultural Research Institute, Jamalpur, Bangladesh
| | | | - Uttam Kumar
- Borlaug Institute for South Asia, Ludhiana, India.,Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
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Ambastha V, Sopory SK, Tripathy BC, Tiwari BS. Salt induced programmed cell death in rice: evidence from chloroplast proteome signature. Funct Plant Biol 2020; 48:8-27. [PMID: 32702286 DOI: 10.1071/fp19356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
Soil salinity, depending on its intensity, drives a challenged plant either to death, or survival with compromised productivity. On exposure to moderate salinity, plants can often survive by sacrificing some of their cells 'in target' following a route called programmed cell death (PCD). In animals, PCD has been well characterised, and involvement of mitochondria in the execution of PCD events has been unequivocally proven. In plants, mechanistic details of the process are still in grey area. Previously, we have shown that in green tissues of rice, for salt induced PCD to occur, the presence of active chloroplasts and light are equally important. In the present work, we have characterised the chloroplast proteome in rice seedlings at 12 and 24 h after salt exposure and before the time point where the signature of PCD was observed. We identified almost 100 proteins from chloroplasts, which were divided in to 11 categories based on the biological functions in which they were involved. Our results concerning the differential expression of chloroplastic proteins revealed involvement of some novel candidates. Moreover, we observed maximum phosphorylation pattern of chloroplastic proteins at an early time point (12 h) of salt exposure.
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Affiliation(s)
- Vivek Ambastha
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sudhir K Sopory
- Plant Molecular Biology, International Centre of Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Baishnab C Tripathy
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India; and Corresponding author. ; ;
| | - Budhi Sagar Tiwari
- Institute of Advanced Research, Gandhinagar, Gujrat 482007, India; and Corresponding author. ; ;
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Waghela BN, Vaidya FU, Ranjan K, Chhipa AS, Tiwari BS, Pathak C. AGE-RAGE synergy influences programmed cell death signaling to promote cancer. Mol Cell Biochem 2020; 476:585-598. [PMID: 33025314 DOI: 10.1007/s11010-020-03928-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 09/23/2020] [Indexed: 12/11/2022]
Abstract
Advanced glycation end products (AGEs) are formed as a result of non-enzymatic reaction between the free reducing sugars and proteins, lipids, or nucleic acids. AGEs are predominantly synthesized during chronic hyperglycemic conditions or aging. AGEs interact with their receptor RAGE and activate various sets of genes and proteins of the signal transduction pathway. Accumulation of AGEs and upregulated expression of RAGE is associated with various pathological conditions including diabetes, cardiovascular diseases, neurodegenerative disorders, and cancer. The role of AGE-RAGE signaling has been demonstrated in the progression of various types of cancer and other pathological disorders. The expression of RAGE increases manifold during cancer progression. The activation of AGE-RAGE signaling also perturbs the cellular redox balance and modulates various cell death pathways. The programmed cell death signaling often altered during the progression of malignancies. The cellular reprogramming of AGE-RAGE signaling with cell death machinery during tumorigenesis is interesting to understand the complex signaling mechanism of cancer cells. The present review focus on multiple molecular paradigms relevant to cell death particularly Apoptosis, Autophagy, and Necroptosis that are considerably influenced by the AGE-RAGE signaling in the cancer cells. Furthermore, the review also attempts to shed light on the provenience of AGE-RAGE signaling on oxidative stress and consequences of cell survival mechanism of cancer cells.
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Affiliation(s)
- Bhargav N Waghela
- Cell Biology Laboratory, School of Biological Sciences & Biotechnology, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Foram U Vaidya
- Cell Biology Laboratory, School of Biological Sciences & Biotechnology, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Kishu Ranjan
- Department of Internal Medicine, Section of Digestive Diseases, Yale University, New Haven, CT, 06519, USA
| | - Abu Sufiyan Chhipa
- Cell Biology Laboratory, School of Biological Sciences & Biotechnology, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Budhi Sagar Tiwari
- Cell Biology Laboratory, School of Biological Sciences & Biotechnology, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India
| | - Chandramani Pathak
- Cell Biology Laboratory, School of Biological Sciences & Biotechnology, Indian Institute of Advanced Research, Koba Institutional Area, Gandhinagar, Gujarat, 382426, India.
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Ambastha V, Chauhan G, Tiwari BS, Tripathy BC. Execution of programmed cell death by singlet oxygen generated inside the chloroplasts of Arabidopsis thaliana. Protoplasma 2020; 257:841-851. [PMID: 31909436 DOI: 10.1007/s00709-019-01467-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
Absorption of excess excitation energy induces overproduction of singlet oxygen (1O2) in plants. The major sources of singlet oxygen production are chlorophyll and its intermediates located in the chloroplast. Over-accumulation of the chlorophyll biosynthetic intermediate protochlorophyllide by the exogenous application of 5-aminolevulinic acid (ALA), the precursor of tetrapyrrole, induced singlet oxygen production in the plastidic membranes. Over-expression of protochlorophyllide oxidoreductase C (PORC) in Arabidopsis thaliana resulted in efficient light-induced photo-transformation of protochlorophyllide to chlorophyllide that limited the accumulation of protochlorophyllide. Consequently, the 1O2 generation decreased in the PORC overexpressors (PORCx) and their cell death was minimal. Conversely, porC-2 over-accumulated protochlorophyllide in response to ALA treatment and generated higher amounts of 1O2 in light and had highest cell death as monitored by Evans blue staining. The protoplasts isolated from PORCx plants, when treated with ALA, generated minimal amounts of 1O2 as revealed by singlet oxygen sensor green (SOSG) fluorescence emission from chloroplasts. Conversely, the protoplasts of porC-2 mutants under identical conditions generated the maximum SOSG fluorescence in their chloroplasts and cytosol surrounding the chloroplasts most likely due to the leakage from the organelle. The membrane blebbing, a hallmark of programmed cell death, was clearly visible in WT and porC-2 protoplasts. Similarly, the nick end labelling (TUNEL) assay revealed nicks in the DNA. The TUNEL-positive nuclei after 30 min of light exposure were highest in porC-2 and lowest in PORCx protoplasts. The results demonstrate that higher amounts of singlet oxygen produced in the chloroplasts play an important role in programmed cell death.
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Affiliation(s)
- Vivek Ambastha
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Garima Chauhan
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Budhi Sagar Tiwari
- School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba, Gandhinagar, Gujarat, 382007, India
| | - Baishnab C Tripathy
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
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Pandey SS, Singh S, Pathak C, Tiwari BS. "Programmed Cell Death: A Process of Death for Survival" - How Far Terminology Pertinent for Cell Death in Unicellular Organisms. J Cell Death 2018; 11:1179066018790259. [PMID: 30116103 PMCID: PMC6088462 DOI: 10.1177/1179066018790259] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 06/22/2018] [Indexed: 02/01/2023] Open
Abstract
Programmed cell death (PCD) is genetically regulated phenomenon of selective elimination of target cells that are either under pathological conditions or unwanted for organism’s normal growth and development due to other reasons. The process although being genetically controlled is physiological in nature that renders some hallmarks like blebs in the cell membrane, lobe formation in nuclear membrane, DNA nicks resulting to DNA ladder of 200 bp, and downstream activation of caspases. Moreover, as the process refers to the death of “targeted cell”, the term is exclusively suitable for multicellular organisms. Number of reports advocate similar type of cell death process in unicellular organisms. As cell death in unicellular organisms is also reflected by the signature of PCD obtained in metazoans, such cell death has been grouped under the broad category of PCD. It is pertinent to mention that by definition a unicellular organism is made of a single cell wherein it carries out all of its life processes. Using the term “Programmed Cell Death” with a preset “survival strategy of the organism” for unicellular organisms looks misnomer. Therefore, this correspondence argues and requests recommendation committee on cell death to revisit for the nomenclature of the cell death process in the unicellular organisms.
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Affiliation(s)
- Shiv Shanker Pandey
- Crop Protection Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Samer Singh
- Department of Microbial Biotechnology, Panjab University, Chandigarh, India
| | - Chandramani Pathak
- Plant Cell Biology & Biotechnology, Institute of Advanced Research (IAR), Gandhinagar, India
| | - Budhi Sagar Tiwari
- Plant Cell Biology & Biotechnology, Institute of Advanced Research (IAR), Gandhinagar, India
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Abstract
In this paper we provide evidence for involvement of chloroplast as alternate organelle for initiating PCD in plants under light and abiotic stress. In animals, mitochondria are the major source of reactive oxygen species (ROS) and key executioner of programmed cell death (PCD). In plants, however, the primary site of generation of ROS is chloroplast and yet its involvement in PCD has not been worked out in details. We found by Evans blue staining that salt (150 mM NaCl)-treated protoplasts obtained from green seedlings had higher rate of cell death than protoplasts obtained from etiolated seedlings. This indicated that cell death induced by NaCl is accentuated by light. Imposition of salt-stress to green protoplasts generated H2O2. Known hallmarks of PCD i.e., blebbing of cell membrane, loabing in nucleus, nick in DNA were observed in light-exposed salt-treated protoplasts and seedlings. TUNEL-FACS assay demonstrate several DNA nicks in the salt-treated green protoplasts exposed to light. Conversely, salt-treated etiolated protoplasts kept in dark had only a few TUNEL-positive nuclei. Similarly, a substantial numbers of TUNEL positive nuclei were observed in green seedlings due to salt treatment in light. However, salt-treated etiolated seedlings kept in dark had very few TUNEL positive nuclei. Addition of Caspase 3 inhibitor (DAVD-CHO) rescued (~50 %) green protoplasts from salt-stress induced cell death suggesting an involvement of apoptosis like PCD (AL-PCD). Ultra structure studies of chloroplast, mitochondria and nucleus from the leaves obtained from salt treated seedlings at the time point that showed PCD signature, resulted to severe granal de-stacking in chloroplasts while structural integrity of mitochondria was maintained. These studies demonstrate the photo-modulation of salinity-induced PCD in photosynthetic tissues is mainly executed by chloroplasts.
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Affiliation(s)
- Vivek Ambastha
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Sudhir K Sopory
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
- Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Budhi Sagar Tiwari
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
- Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India.
| | - Baishnab C Tripathy
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India.
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Thagela P, Yadav RK, Mishra V, Dahuja A, Ahmad A, Singh PK, Tiwari BS, Abraham G. Salinity-induced inhibition of growth in the aquatic pteridophyte Azolla microphylla primarily involves inhibition of photosynthetic components and signaling molecules as revealed by proteome analysis. Protoplasma 2017; 254:303-313. [PMID: 26837223 DOI: 10.1007/s00709-016-0946-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 01/18/2016] [Indexed: 05/21/2023]
Abstract
Salinity stress causes adverse physiological and biochemical changes in the growth and productivity of a plant. Azolla, a symbiotic pteridophyte and potent candidate for biofertilizer due to its nitrogen fixation ability, shows reduced growth and nitrogen fixation during saline stress. To better understand regulatory components involved in salinity-induced physiological changes, in the present study, Azolla microphylla plants were exposed to NaCl (6.74 and 8.61 ds/m) and growth, photochemical reactions of photosynthesis, ion accumulation, and changes in cellular proteome were studied. Maximum dry weight was accumulated in control and untreated plant while a substantial decrease in dry weight was observed in the plants exposed to salinity. Exposure of the organism to different concentrations of salt in hydroponic conditions resulted in differential level of Na+ and K+ ion accumulation. Comparative analysis of salinity-induced proteome changes in A. microphylla revealed 58 salt responsive proteins which were differentially expressed during the salt exposure. Moreover, 42 % spots among differentially expressed proteins were involved in different signaling events. The identified proteins are involved in photosynthesis, energy metabolism, amino acid biosynthesis, protein synthesis, and defense. Downregulation of these key metabolic proteins appears to inhibit the growth of A. microphylla in response to salinity. Altogether, the study revealed that in Azolla, increased salinity primarily affected signaling and photosynthesis that in turn leads to reduced biomass.
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Affiliation(s)
- Preeti Thagela
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Ravindra Kumar Yadav
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Vagish Mishra
- NRCPB, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India
| | - Anil Dahuja
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Altaf Ahmad
- Department of Botany, Aligarh Muslim University, Aligarh, U.P., India
| | - Pawan Kumar Singh
- Department of Botany, Banaras Hindu University, Varanasi, 221005, U.P., India
| | - Budhi Sagar Tiwari
- School of Biological Sciences and Biotechnology, University and Institute of Advanced Research, Gandhinagar, 382007, Gujrat, India
| | - Gerard Abraham
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
- Centre for Conservation and Utilization of BGA, CCUBGA, NEAR AUDITORIUM, New Delhi, 110012, India.
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13
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Tripathy MK, Tiwari BS, Reddy MK, Deswal R, Sopory SK. Ectopic expression of PgRab7 in rice plants (Oryza sativa L.) results in differential tolerance at the vegetative and seed setting stage during salinity and drought stress. Protoplasma 2017; 254:109-124. [PMID: 26666551 DOI: 10.1007/s00709-015-0914-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 11/19/2015] [Indexed: 05/23/2023]
Abstract
In this work, we have overexpressed a vesicle trafficking protein, Rab7, from a stress-tolerant plant, Pennisetum glaucum, in a high-yielding but stress-sensitive rice variety Pusa Basmati-1 (PB-1). The transgenic rice plants were tested for tolerance against salinity and drought stress. The transgenic plants showed considerable tolerance at the vegetative stage against both salinity (200 mM NaCl) and drought stress (up to 12 days after withdrawing water). The protection against salt and drought stress may be by regulating Na+ ion homeostasis, as the transgenic plants showed altered expression of multiple transporter genes, including OsNHX1, OsNHX2, OsSOS1, OsVHA, and OsGLRs. In addition, decreased generation and maintenance of lesser reactive oxygen species (ROS), with maintenance of chloroplast grana and photosynthetic machinery was observed. When evaluated for reproductive growth, 89-96 % of seed setting was maintained in transgenic plants during drought stress; however, under salt stress, a 33-53 % decrease in seed setting was observed. These results indicate that PgRab7 overexpression in rice confers differential tolerance at the seed setting stage during salinity and drought stress and could be a favored target for raising drought-tolerant crops.
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Affiliation(s)
- Manas Kumar Tripathy
- Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India.
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA.
| | - Budhi Sagar Tiwari
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Malireddy K Reddy
- Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Renu Deswal
- Department of Botany, University of Delhi, Delhi, 110007, India
| | - Sudhir K Sopory
- Plant Molecular Biology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India.
- Jawaharlal Nehru University, New Delhi, 110067, India.
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14
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Ambastha V, Tripathy BC, Tiwari BS. Programmed cell death in plants: A chloroplastic connection. Plant Signal Behav 2015; 10:e989752. [PMID: 25760871 PMCID: PMC4622501 DOI: 10.4161/15592324.2014.989752] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 11/12/2014] [Accepted: 11/13/2014] [Indexed: 05/18/2023]
Abstract
Programmed cell death (PCD) is an integral cellular program by which targeted cells culminate to demise under certain developmental and pathological conditions. It is essential for controlling cell number, removing unwanted diseased or damaged cells and maintaining the cellular homeostasis. The details of PCD process has been very well elucidated and characterized in animals but similar understanding of the process in plants has not been achieved rather the field is still in its infancy that sees some sporadic reports every now and then. The plants have 2 energy generating sub-cellular organelles- mitochondria and chloroplasts unlike animals that just have mitochondria. The presence of chloroplast as an additional energy transducing and ROS generating compartment in a plant cell inclines to advocate the involvement of chloroplasts in PCD execution process. As chloroplasts are supposed to be progenies of unicellular photosynthetic organisms that evolved as a result of endosymbiosis, the possibility of retaining some of the components involved in bacterial PCD by chloroplasts cannot be ruled out. Despite several excellent reviews on PCD in plants, there is a void on an update of information at a place on the regulation of PCD by chloroplast. This review has been written to provide an update on the information supporting the involvement of chloroplast in PCD process and the possible future course of the field.
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Affiliation(s)
- Vivek Ambastha
- School of Life Sciences; Jawaharlal Nehru University; New Delhi, India
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15
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Govrin EM, Rachmilevitch S, Tiwari BS, Solomon M, Levine A. An Elicitor from Botrytis cinerea Induces the Hypersensitive Response in Arabidopsis thaliana and Other Plants and Promotes the Gray Mold Disease. Phytopathology 2006; 96:299-307. [PMID: 18944445 DOI: 10.1094/phyto-96-0299] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
ABSTRACT Botrytis cinerea is a necrotrophic fungus that infects over 200 plant species. Previous studies showed that host cells collapse in advance of the hyphae, suggesting secretion of toxins or elicitors. We have partially characterized elicitor activity from intercellular fluid extracted from Arabidopsis thaliana leaves infected with B. cinerea. Treatment of intact leaves or cell cultures with either intercellular fluid from infected leaves or medium from inoculated A. thaliana cell culture induced generation of reactive oxygen species, resulting in reduced photosynthesis, electrolyte leakage, and necrotic lesions that resembled the hypersensitive response (HR). The necrosis was inhibited by diphenyleneiodonium, a specific inhibitor of NADPH oxidase, and by chelating free iron, suggesting the involvement of hydroxyl radicals. The necrosis was also suppressed in dnd1 mutants that are compromised in HR. In contrast, increased cell death was observed in acd2 mutants, indicating the involvement of the host defense signaling pathways. Treatment with the intercellular fluid from infected leaves also induced transcription of pathogenesis-related (PR) genes, such as PR-1, PR-5, HSR203J, and of senescence-associated gene SAG-13. Moreover, rapid transcription of the ethylene-dependent AtEBP gene was detected, indicating induction of ethylene production. The inter-cellular fluid from infected A. thaliana induced cell death in other plants, in line with the lack of B. cinerea specificity. In summary, the intercellular fluid mimicked a range of molecular and physiological host responses that are observed during infection with a live fungus. Moreover, it accelerated the B. cinerea infection, suggesting that the elicitor may act as a pathogenicity factor in the progression of gray mold disease.
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16
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Capone R, Tiwari BS, Levine A. Rapid transmission of oxidative and nitrosative stress signals from roots to shoots in Arabidopsis. Plant Physiol Biochem 2004; 42:425-428. [PMID: 15191746 DOI: 10.1016/j.plaphy.2004.03.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2003] [Accepted: 03/09/2004] [Indexed: 05/24/2023]
Abstract
Protein kinases play a central role in signal transduction pathways in eukaryotes. A highly conserved group of kinases, termed mitogen-activated-protein kinases (MAPKs) was shown to mediate many diverse stress responses. In plants, MAPKs were shown to function in resistance responses to many biotic and abiotic stresses. Here, we show that exposure of Arabidopsis roots to hydrogen peroxide or to nitric oxide resulted in rapid activation of protein kinases in the shoots that exhibited MAPK properties. The same pattern of kinases was induced by direct injection of these compounds into leaves, indicating accurate long-distance transmission of H2O2 and NO signals. These results are important for the understanding of redox signal transmission from the rhizosphere throughout the plant.
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Affiliation(s)
- Ricardo Capone
- Department of Plant Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904, Israel
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17
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Mazel A, Leshem Y, Tiwari BS, Levine A. Induction of salt and osmotic stress tolerance by overexpression of an intracellular vesicle trafficking protein AtRab7 (AtRabG3e). Plant Physiol 2004; 134:118-28. [PMID: 14657401 PMCID: PMC316292 DOI: 10.1104/pp.103.025379] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2003] [Revised: 05/07/2003] [Accepted: 07/07/2003] [Indexed: 05/18/2023]
Abstract
Adaptation to stress requires removal of existing molecules from various cellular compartments and replacing them with new ones. The transport of materials to and from the specific compartments involved in the recycling and deposition of macromolecules is carried out by an intracellular vesicle trafficking system. Here, we report the isolation of a vesicle trafficking-regulating gene, AtRabG3e (formerly AtRab7), from Arabidopsis. The gene was induced during programmed cell death after treatment of intact leaves with superoxide and salicylic acid or infection with necrogenic pathogens. Transgenic plants that expressed the AtRabG3e gene under the constitutive 35S promoter from cauliflower mosaic virus exhibited accelerated endocytosis in roots, leaves, and protoplasts. The transgenic plants accumulated sodium in the vacuoles and had higher amounts of sodium in the shoots. The transgenic plants also showed increased tolerance to salt and osmotic stresses and reduced accumulation of reactive oxygen species during salt stress. These results imply that vesicle trafficking plays an important role in plant adaptation to stress, beyond the housekeeping function in intracellular vesicle trafficking.
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Affiliation(s)
- Alexander Mazel
- Department of Plant Sciences, Institute of Life Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904, Israel
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18
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Chattopadhayay MK, Tiwari BS, Chattopadhyay G, Bose A, Sengupta DN, Ghosh B. Protective role of exogenous polyamines on salinity-stressed rice (Oryza sativa) plants. Physiol Plant 2002; 116:192-199. [PMID: 12354195 DOI: 10.1034/j.1399-3054.2002.1160208.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Salt-tolerant Pokkali rice plants accumulate higher polyamines (PAs) such as spermidine (Spd) and spermine (Spm) in response to salinity stress, while the sensitive cultivarM-1-48 is unable to maintain high titres of these PAs under similar conditions. The effects of the triamine Spd and the tetramine Spm on physiological and biochemical changes in 12-day-old rice seedlings were investigated during salinity stress to determine whether they could protect the sensitive plants from stress effects. At physiological concentrations Spd and Spm significantly prevented the leakage of electrolytes and amino acids from roots and shoots induced by salinity stress. To different degrees they also prevented chlorophyll loss, inhibition of photochemical reactions of photosynthesis as well as downregulation of chloroplast-encoded genes like psbA, psbB, psbE and rbcL, indicating a positive correlation between salt tolerance and accumulation of higher PAs in rice. The inhibitory effect of salinity stress and its reversal by exogenous PAs were more pronounced in the salt-sensitiveM-1-48 plants than in the tolerant Pokkali plants.
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Affiliation(s)
- Manas Kumar Chattopadhayay
- Department of Botany, Bose Institute, 93/1 A.P.C. Road, Calcutta 700 009, India Present address: Department of Plant Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904, Israel
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Tiwari BS, Belenghi B, Levine A. Oxidative stress increased respiration and generation of reactive oxygen species, resulting in ATP depletion, opening of mitochondrial permeability transition, and programmed cell death. Plant Physiol 2002; 128:1271-81. [PMID: 11950976 PMCID: PMC154255 DOI: 10.1104/pp.010999] [Citation(s) in RCA: 314] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2001] [Accepted: 01/18/2002] [Indexed: 05/17/2023]
Abstract
Mitochondria constitute a major source of reactive oxygen species and have been proposed to integrate the cellular responses to stress. In animals, it was shown that mitochondria can trigger apoptosis from diverse stimuli through the opening of MTP, which allows the release of the apoptosis-inducing factor and translocation of cytochrome c into the cytosol. Here, we analyzed the role of the mitochondria in the generation of oxidative burst and induction of programmed cell death in response to brief or continuous oxidative stress in Arabidopsis cells. Oxidative stress increased mitochondrial electron transport, resulting in amplification of H(2)O(2) production, depletion of ATP, and cell death. The increased generation of H(2)O(2) also caused the opening of the MTP and the release of cytochrome c from mitochondria. The release of cytochrome c and cell death were prevented by a serine/cysteine protease inhibitor, Pefablock. However, addition of inhibitor only partially inhibited the H(2)O(2) amplification and the MTP opening, suggesting that protease activation is a necessary step in the cell death pathway after mitochondrial damage.
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Affiliation(s)
- Budhi Sagar Tiwari
- Department of Plant Sciences, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Givat-Ram, Jerusalem 91904, Israel
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20
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Tiwari BS, Tripathi SN. Effect of hydration and dehydration on initiation and dynamics of some physiological reactions in desiccation tolerant cyanobacterium Scytonema geitleri. Indian J Biochem Biophys 1998; 35:172-8. [PMID: 9803667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The effect of hydration and dehydration has been studied on extent and recovery of some metabolic reactions in desiccation tolerant terrestrial cyanobacterium Scytonema geitleri. The results show that the energy transducing reactions like photochemical reactions of photosynthesis recover first, followed by increase in ATP pool size. During later phase of hydration, appearance of energy consuming processes such as CO2 fixation and nitrogen fixation have been observed. Sensitivity of reactions during dehydration followed the pattern reverse to recovery processes.
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Affiliation(s)
- B S Tiwari
- Center for Advanced Study in Botany, Banaras Hindu University, Varanasi, India
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21
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Tiwari BS, Tripathi SN. Water binding in sub-aerial cyanobacteria. Indian J Biochem Biophys 1998; 35:52-61. [PMID: 9699420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The role of water in the maintenance of structural and functional integrity of the cell at different hydration levels has been a subject of wide understanding. Water sorption isotherms, dielectrics and IR spectroscopic techniques were used to estimate the strength of water binding and number of binding sites using D'Arcy/Watt equation on the two well reported desiccation-tolerant cyanobacteria-Scytonema geitleri and Lyngbya arboricola. The observations made with water sorption isotherms, dielectrics and IR spectroscopic techniques clearly indicate three water binding regions. Grown mats of both the cyanobacteria showed high number of water binding sites onto strong binding region compared to their dry counterparts.
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Affiliation(s)
- B S Tiwari
- Centre of Adanced Study in Botany, Banaras Hindu University, Varanasi, India
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