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Mulaudzi T, Sias G, Nkuna M, Ndou N, Hendricks K, Ikebudu V, Koo AJ, Ajayi RF, Iwuoha E. Seed Priming with MeJa Prevents Salt-Induced Growth Inhibition and Oxidative Damage in Sorghum bicolor by Inducing the Expression of Jasmonic Acid Biosynthesis Genes. Int J Mol Sci 2023; 24:10368. [PMID: 37373514 DOI: 10.3390/ijms241210368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
Salinity is one of the major detrimental abiotic stresses at the forefront of deterring crop productivity globally. Although the exogenous application of phytohormones has formerly proven efficacious to plants, their effect on the moderately stress-tolerant crop "Sorghum bicolor" remains elusive. To investigate this, S. bicolor seeds primed with methyl jasmonate (0; 10 and 15 μM MeJa) were exposed to salt (200 mM NaCl) stress, and their morpho-physiological, biochemical, and molecular attributes were measured. Salt stress significantly decreased shoot length and fresh weight by 50%, whereas dry weight and chlorophyll content were decreased by more than 40%. Furthermore, salt-stress-induced oxidative damage was evident by the formation of brown formazan spots (indicative of H2O2 production) on sorghum leaves and a more than 30% increase in MDA content. However, priming with MeJa improved growth, increased chlorophyll content, and prevented oxidative damage under salt stress. While 15 µM MeJa maintained proline content to the same level as the salt-stressed samples, total soluble sugars were maintained under 10 µM MeJa, indicating a high degree of osmotic adjustment. Shriveling and thinning of the epidermis and xylem tissues due to salt stress was prevented by MeJa, followed by a more than 70% decrease in the Na+/K+ ratio. MeJa also reversed the FTIR spectral shifts observed for salt-stressed plants. Furthermore, salt stress induced the expression of the jasmonic acid biosynthesis genes; linoleate 92-lipoxygenase 3, allene oxide synthase 1, allene oxide cyclase, and 12-oxophytodienoate reductase 1. In MeJa-primed plants, their expression was reduced, except for the 12-oxophytodienoate reductase 1 transcript, which further increased by 67%. These findings suggest that MeJa conferred salt-stress tolerance to S. bicolor through osmoregulation and synthesis of JA-related metabolites.
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Affiliation(s)
- Takalani Mulaudzi
- Life Sciences Building, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Gershwin Sias
- Life Sciences Building, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Mulisa Nkuna
- Life Sciences Building, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Nzumbululo Ndou
- Life Sciences Building, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
- SensorLab, Department of Chemical Sciences, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Kaylin Hendricks
- Life Sciences Building, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Vivian Ikebudu
- Life Sciences Building, Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Abraham J Koo
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Rachel F Ajayi
- SensorLab, Department of Chemical Sciences, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
| | - Emmanuel Iwuoha
- SensorLab, Department of Chemical Sciences, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
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Sorghum's Whole-Plant Transcriptome and Proteome Responses to Drought Stress: A Review. Life (Basel) 2021; 11:life11070704. [PMID: 34357076 PMCID: PMC8305457 DOI: 10.3390/life11070704] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/12/2021] [Accepted: 07/15/2021] [Indexed: 12/29/2022] Open
Abstract
Sorghum is a cereal crop with key agronomic traits of drought and heat stress tolerance, making it an ideal food and industrial commodity for hotter and more arid climates. These stress tolerances also present a useful scientific resource for studying the molecular basis for environmental resilience. Here we provide an extensive review of current transcriptome and proteome works conducted with laboratory, greenhouse, or field-grown sorghum plants exposed to drought, osmotic stress, or treated with the drought stress-regulatory phytohormone, abscisic acid. Large datasets from these studies reveal changes in gene/protein expression across diverse signaling and metabolic pathways. Together, the emerging patterns from these datasets reveal that the overall functional classes of stress-responsive genes/proteins within sorghum are similar to those observed in equivalent studies of other drought-sensitive model species. This highlights a monumental challenge of distinguishing key regulatory genes/proteins, with a primary role in sorghum adaptation to drought, from genes/proteins that change in expression because of stress. Finally, we discuss possible options for taking the research forward. Successful exploitation of sorghum research for implementation in other crops may be critical in establishing climate-resilient agriculture for future food security.
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Zhou M, Malhan N, Ahkami AH, Engbrecht K, Myers G, Dahlberg J, Hollingsworth J, Sievert JA, Hutmacher R, Madera M, Lemaux PG, Hixson KK, Jansson C, Paša-Tolić L. Top-down mass spectrometry of histone modifications in sorghum reveals potential epigenetic markers for drought acclimation. Methods 2020; 184:29-39. [DOI: 10.1016/j.ymeth.2019.10.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/10/2019] [Accepted: 10/21/2019] [Indexed: 12/30/2022] Open
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Goche T, Shargie NG, Cummins I, Brown AP, Chivasa S, Ngara R. Comparative physiological and root proteome analyses of two sorghum varieties responding to water limitation. Sci Rep 2020; 10:11835. [PMID: 32678202 PMCID: PMC7366710 DOI: 10.1038/s41598-020-68735-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 06/09/2020] [Indexed: 01/31/2023] Open
Abstract
When exposed to drought stress many plants reprogram their gene expression to activate adaptive biochemical and physiological responses for survival. However, most of the well-studied adaptive responses are common between drought-sensitive and drought-tolerant species, making it difficult to identify the key mechanisms underpinning successful drought tolerance in crops. We developed a sorghum experimental system that compares between drought-sensitive (ICSB338) and enhanced drought-tolerant (SA1441) varieties. We show that sorghum activates a swift and robust stomatal shutdown to preserve leaf water content when water stress has been sensed. Water uptake is enhanced via increasing root cell water potential through the rapid biosynthesis of predominantly glycine betaine and an increased root-to-shoot ratio to explore more soil volume for water. In addition to stomatal responses, there is a prompt accumulation of proline in leaves and effective protection of chlorophyll during periods of water limitation. Root and stomatal functions rapidly recover from water limitation (within 24 h of re-watering) in the drought-tolerant variety, but recovery is impaired in the drought-sensitive sorghum variety. Analysis of the root proteome revealed complex protein networks that possibly underpin sorghum responses to water limitation. Common and unique protein changes between the two sorghum varieties provide new targets for future use in investigating sorghum drought tolerance.
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Affiliation(s)
- Tatenda Goche
- Department of Plant Sciences, University of the Free State, Qwaqwa Campus, P. Bag X13, Phuthaditjhaba, South Africa
| | - Nemera G Shargie
- Agricultural Research Council-Grain Crops Institute, P. Bag X1251, Potchefstroom, 2520, South Africa
| | - Ian Cummins
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Adrian P Brown
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK
| | - Stephen Chivasa
- Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK.
| | - Rudo Ngara
- Department of Plant Sciences, University of the Free State, Qwaqwa Campus, P. Bag X13, Phuthaditjhaba, South Africa.
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Sanjari S, Shirzadian-Khorramabad R, Shobbar ZS, Shahbazi M. Systematic analysis of NAC transcription factors' gene family and identification of post-flowering drought stress responsive members in sorghum. PLANT CELL REPORTS 2019; 38:361-376. [PMID: 30627770 DOI: 10.1007/s00299-019-02371-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 01/02/2019] [Indexed: 05/25/2023]
Abstract
SbNAC genes (131) encoding 183 proteins were identified from the sorghum genome and characterized. The expression patterns of SbSNACs were evaluated at three sampling time points under post-flowering drought stress. NAC proteins are specific transcription factors in plants, playing vital roles in development and response to various environmental stresses. Despite the fact that Sorghum bicolor is well-known for its drought-tolerance, it suffers from grain yield loss due to pre and post-flowering drought stress. In the present study, 131 SbNAC genes encoding 183 proteins were identified from the sorghum genome. The phylogenetic trees were constructed based on the NAC domains of sorghum, and also based on sorghum with Arabidopsis and 8 known NAC domains of other plants, which classified the family into 15 and 19 subfamilies, respectively. Based on the obtained results, 13 SbNAC proteins joined the SNAC subfamily, and these proteins are expected to be involved in response to abiotic stresses. Promoter analysis revealed that all SbNAC genes comprise different stress-associated cis-elements in their promoters. UTRs analysis indicated that 101 SbNAC transcripts had upstream open reading frames, while 39 of the transcripts had internal ribosome entry sites in their 5'UTR. Moreover, 298 miRNA target sites were predicted to exist in the UTRs of SbNAC transcripts. The expression patterns of SbSNACs were evaluated in three genotypes at three sampling time points under post-flowering drought stress. Based on the results, it could be suggested that some gene members are involved in response to drought stress at the post-flowering stage since they act as positive or negative transcriptional regulators. Following further functional analyses, some of these genes might be perceived to be promising candidates for breeding programs to enhance drought tolerance in crops.
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Affiliation(s)
- Sepideh Sanjari
- Department of Agricultural Biotechnology, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran
| | - Reza Shirzadian-Khorramabad
- Department of Agricultural Biotechnology, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran
| | - Zahra-Sadat Shobbar
- Department of Systems Biology, Agricultural Biotechnology Research Institute of Iran, Education and Extension Organization (AREEO), Karaj, Iran.
| | - Maryam Shahbazi
- Department of Molecular Physiology, Agricultural Biotechnology Research Institute of Iran, Education and Extension Organization (AREEO), Karaj, Iran
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Zhang T, Zhao X, Wang W, Huang L, Liu X, Zong Y, Zhu L, Yang D, Fu B, Li Z. Deep transcriptome sequencing of rhizome and aerial-shoot in Sorghum propinquum. PLANT MOLECULAR BIOLOGY 2014; 84:315-27. [PMID: 24104862 DOI: 10.1007/s11103-013-0135-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 09/23/2013] [Indexed: 05/25/2023]
Abstract
Transcriptomic data for Sorghum propinquum, the wild-type sorghum, are limited in public databases. S. propinquum has a subterranean rhizome and transcriptome data will help in understanding the molecular mechanisms underlying rhizome formation. We sequenced the transcriptome of S. propinquum aerial-shoot and rhizome using an Illumina platform. More than 70 % of the genes in the S. propinquum genome were expressed in aerial-shoot and rhizome. The expression patterns of 1963 and 599 genes, including transcription factors, were specific or enriched in aerial-shoot and rhizome respectively, indicating their possible roles in physiological processes in these tissues. Comparative analysis revealed several cis-elements, ACGT box, GCCAC, GATC and TGACG box, which showed significantly higher abundance in aerial-shoot-specific genes. In rhizome-specific genes MYB and ROOTMOTIFTAPOX1 motifs, and 10 promoter and cytokinin-responsive elements were highly enriched. Of the S. propinquum genes, 27.9 % were identified as alternatively spliced and about 60 % of the alternative splicing (AS) events were tissue-specific, suggesting that AS played a crucial role in determining tissue-specific cellular function. The transcriptome data, especially the co-localized rhizome-enriched expressed transcripts that mapped to the publicly available rhizome-related quantitative trait loci, will contribute to gene discovery in S. propinquum and to functional studies of the sorghum genome. Deep transcriptome sequencing revealed a clear difference in the expression patterns of genes between aerial-shoot and rhizome in S. propinquum. This data set provides essential information for future studies into the molecular genetic mechanisms involved in rhizome formation.
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Affiliation(s)
- Ting Zhang
- Institute of Crop Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Sciences, 12 South Zhong-Guan-Cun St., Beijing, 100081, China
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7
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Shanker AK, Maddaala A, Kumar MA, Yadav SK, Maheswari M, Venkateswarlu B. In silico targeted genome mining and comparative modelling reveals a putative protein similar to an Arabidopsis drought tolerance DNA binding transcription factor in Chromosome 6 of Sorghum bicolor genome. Interdiscip Sci 2012; 4:133-41. [PMID: 22843236 DOI: 10.1007/s12539-012-0121-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 01/11/2012] [Accepted: 01/25/2012] [Indexed: 11/25/2022]
Abstract
Arabidopsis Thaliana HARDY (AtHRD) is a gene with an APETELA 2 / Ethylene Responsive Factor (AP2/ERF) domain linked to improved performance under drought in rice. We hypothesized that the sorghum genome could possess a similar gene product and were motivated to conduct a computational genome scale mining for the protein and analyse its structural and functional properties. AtHRD sequence was used as a query to BLAST against the sorghum genome dataset followed by multiple alignment analysis. A homology model of the target was built using a template detected based on the pair-wise comparison of hidden Markov models for alignments. DNA docking with a matrix of homologous interface contacts was done. Functional and structural analysis of the query and target was conducted using various online servers. A High-scoring segment pair from Chromosome 6 of the sorghum genome in the region between 54948120 and 54948668 had 68 amino acid similarities out of the 184 residues and was 1.4% above twilight zone threshold. The homology model showed 86.8% residues in most favoured regions. The target protein which had an AP2/ERF domain when docked with GCC box DNA motif had conserved residues involved in binding; it had a long unstructured region beyond the AP2 domain with several motifs for the recognition of serine/threonine protein kinase group. The protein model showed that it could bind to a GCC box which is present in several drought responsive genes. The presence of possible signalling domains and intrinsic disorder in the target protein suggest that this could play a role in drought tolerance which is an inherent character of sorghum. These results offer a jumpstart for validation experiments which could pave the way for cis/trans genic improvement of a range of crops.
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Affiliation(s)
- Arun K Shanker
- Division of Crop Sciences, Central Research Institute for Dryland Agriculture (CRIDA), Santosh Nagar, Saidabad P.O., Hyderabad, 500059, India.
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8
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Sabadin PK, Malosetti M, Boer MP, Tardin FD, Santos FG, Guimarães CT, Gomide RL, Andrade CLT, Albuquerque PEP, Caniato FF, Mollinari M, Margarido GRA, Oliveira BF, Schaffert RE, Garcia AAF, van Eeuwijk FA, Magalhaes JV. Studying the genetic basis of drought tolerance in sorghum by managed stress trials and adjustments for phenological and plant height differences. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2012; 124:1389-402. [PMID: 22297563 DOI: 10.1007/s00122-012-1795-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 01/05/2012] [Indexed: 05/25/2023]
Abstract
Managed environments in the form of well watered and water stressed trials were performed to study the genetic basis of grain yield and stay green in sorghum with the objective of validating previously detected QTL. As variations in phenology and plant height may influence QTL detection for the target traits, QTL for flowering time and plant height were introduced as cofactors in QTL analyses for yield and stay green. All but one of the flowering time QTL were detected near yield and stay green QTL. Similar co-localization was observed for two plant height QTL. QTL analysis for yield, using flowering time/plant height cofactors, led to yield QTL on chromosomes 2, 3, 6, 8 and 10. For stay green, QTL on chromosomes 3, 4, 8 and 10 were not related to differences in flowering time/plant height. The physical positions for markers in QTL regions projected on the sorghum genome suggest that the previously detected plant height QTL, Sb-HT9-1, and Dw2, in addition to the maturity gene, Ma5, had a major confounding impact on the expression of yield and stay green QTL. Co-localization between an apparently novel stay green QTL and a yield QTL on chromosome 3 suggests there is potential for indirect selection based on stay green to improve drought tolerance in sorghum. Our QTL study was carried out with a moderately sized population and spanned a limited geographic range, but still the results strongly emphasize the necessity of corrections for phenology in QTL mapping for drought tolerance traits in sorghum.
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Affiliation(s)
- P K Sabadin
- Embrapa Maize and Sorghum, Rod. MG 424, Km 65, Sete Lagoas, MG 35701-970, Brazil
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9
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Savadi SB, Fakrudin B, Nadaf HL, Gowda MVC. Transferability of Sorghum Genic Microsatellite Markers to Peanut. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/ajps.2012.39142] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Monteiro MS, Rodriguez E, Loureiro J, Mann RM, Soares AMVM, Santos C. Flow cytometric assessment of Cd genotoxicity in three plants with different metal accumulation and detoxification capacities. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2010; 73:1231-7. [PMID: 20663557 DOI: 10.1016/j.ecoenv.2010.06.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 03/24/2010] [Accepted: 06/26/2010] [Indexed: 05/29/2023]
Abstract
Cadmium (Cd) is a widespread environmental contaminant, strongly mutagenic and known to cause DNA damage in plants. In this work, flow cytometry (FCM) was applied to determine if in vivo exposure to Cd would induce genotoxic effects at the genome level. The hyper-accumulator Thlaspi caerulescens (J. & C. Presl), the related non-accumulator Thlaspi arvense L. and the accumulator crop species Lactuca sativa L. were germinated in distilled water and grown in modified Hoagland's medium with increasing concentrations of Cd(NO3)2 (0, 1, 10 and 100 microM). After 28 days of exposure, shoot and root growth was recorded and the tissues were harvested for Cd and FCM analysis. In general, roots from treated plants contained higher content of Cd than leaves and growth inhibition was observed in the treated plants. Nuclear DNA content was estimated and the G0/G1 full peak coefficient of variation (FPCV), as an indicator of clastogenic damage, was recorded. In T. arvense and T. caerulescens no significant differences were detected between control and exposed plants. Leaves of L. sativa exposed to 10 microM Cd presented a statistically significant increase in FPCV values in comparison with the control group. Furthermore, roots exposed to 100 microM Cd presented a reduction in nuclear DNA content and an increase in FPCV when compared to the control. FCM data indicates that no major DNA damage was induced on both Cd-exposed Thlaspi species and L. sativa leaves. On the contrary, results obtained with L. sativa roots suggests clastogenic damage in these organs exposed to 100 microM of Cd.
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Affiliation(s)
- M S Monteiro
- CESAM & Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal.
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Strable J, Scanlon MJ. Maize (Zea mays): a model organism for basic and applied research in plant biology. Cold Spring Harb Protoc 2010; 2009:pdb.emo132. [PMID: 20147033 DOI: 10.1101/pdb.emo132] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Zea mays ssp. mays is one of the world's most important crop plants, boasting a multibillion dollar annual revenue. In addition to its agronomic importance, maize has been a keystone model organism for basic research for nearly a century. Within the cereals, which include other plant model species such as rice (Oryza sativa), sorghum (Sorghum bicolor), wheat (Triticum spp.), and barley (Hordeum vulgare), maize is the most thoroughly researched genetic system. Several attributes of the maize plant, including a vast collection of mutant stocks, large heterochromatic chromosomes, extensive nucleotide diversity, and genic colinearity within related grasses, have positioned this species as a centerpiece for genetic, cytogenetic, and genomic research. As a model organism, maize is the subject of such far-ranging biological investigations as plant domestication, genome evolution, developmental physiology, epigenetics, pest resistance, heterosis, quantitative inheritance, and comparative genomics. These and other studies will be advanced by the completed sequencing and annotation of the maize gene space, which will be realized during 2009. Here we present an overview of the use of maize as a model system and provide links to several protocols that enable its genetic and genomic analysis.
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Affiliation(s)
- Josh Strable
- Department of Plant Biology, Cornell University, Ithaca, NY 14853, USA
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12
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Jain M, Chourey PS, Li QB, Pring DR. Expression of cell wall invertase and several other genes of sugar metabolism in relation to seed development in sorghum (Sorghum bicolor). JOURNAL OF PLANT PHYSIOLOGY 2008; 165:331-44. [PMID: 17293002 DOI: 10.1016/j.jplph.2006.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 12/02/2006] [Accepted: 12/02/2006] [Indexed: 05/06/2023]
Abstract
We report expression profiles of several genes of carbohydrate metabolism, cell wall invertase (CWI) in particular, to better understand sugar transport and its utilization in developing caryopses of grain sorghum [Sorghum bicolor (L.) Moench]. Gene expression analyses for CWI using RNA gel blot and real-time quantitative PCR approaches on developing caryopses, including the glumes (maternal tissue appended to the seeds), showed expression of SbIncw (ZmIncw2 ortholog) primarily in the basal sugar unloading zone of endosperm. The expression of ZmIncw1 ortholog was significantly less abundant and restricted to the glumes. The protein and enzyme activity data corroborated the temporal transcript expression profile that showed maximal CWI protein (INCW) expression preceding the starch-filling phase of endosperm development, i.e. 6-12d-after-pollination (DAP). Protein gel blot analysis using polyclonal maize INCW1 antibodies showed a single polypeptide of 72kDa. The highest level of enzyme activity was unique to the basal part of the endosperm, in particular the basal endosperm transfer cell (BETC) layer and the maternal pedicel region that were highly enriched for the INCW protein, as seen by immunolocalization. High hexose-to-sucrose ratio in 6-12 DAP seeds, and negligible starch deposition in glumes corroborated the CWI activity data. Additionally, we report transcription profiles of several other genes related to sugar-to-starch metabolism in developing sorghum endosperm. As in maize, the INCW-mediated apoplastic cleavage of sucrose in the BETC and pedicel during the early developmental stages of caryopses is essential for the normal development of filial tissues. The unique cell-specificity of the INCW protein to both proximal and distal ends of placental sac shown here for the first time is likely to greatly increase uptakes of both hexose sugars and water through turgor sensing into developing seed. This trait is unique to sorghum among cereals and may facilitate its survival in drought environment.
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Affiliation(s)
- Mukesh Jain
- Department of Plant Pathology, University of Florida, Gainesville, FL 32611-0680, USA
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Cordeiro GM, Eliott F, McIntyre CL, Casu RE, Henry RJ. Characterisation of single nucleotide polymorphisms in sugarcane ESTs. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2006; 113:331-43. [PMID: 16791699 DOI: 10.1007/s00122-006-0300-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Accepted: 04/21/2006] [Indexed: 05/04/2023]
Abstract
Commercial sugarcane cultivars (Saccharum spp. hybrids) are both polyploid and aneuploid with chromosome numbers in excess of 100; these chromosomes can be assigned to 8 homology groups. To determine the utility of single nucleotide polymorphisms (SNPs) as a means of improving our understanding of the complex sugarcane genome, we developed markers to a suite of SNPs identified in a list of sugarcane ESTs. Analysis of 69 EST contigs showed a median of 9 SNPs per EST and an average of 1 SNP per 50 bp of coding sequence. The quantitative presence of each base at 58 SNP loci within 19 contiguous sequence sets was accurately and reliably determined for 9 sugarcane genotypes, including both commercial cultivars and ancestral species, through the use of quantitative light emission technology in pyrophosphate sequencing. Across the 9 genotypes tested, 47 SNP loci were polymorphic and 11 monomorphic. Base frequency at individual SNP loci was found to vary approximately twofold between Australian sugarcane cultivars and more widely between cultivars and wild species. Base quantity was shown to segregate as expected in the IJ76-514 x Q165 sugarcane mapping population, indicating that SNPs that occur on one or two sugarcane chromosomes have the potential to be mapped. The use of SNP base frequencies from five of the developed markers was able to clearly distinguish all genotypes in the population. The use of SNP base frequencies from a further six markers within an EST contig was able to help establish the likely copy number of the locus in two genotypes tested. This is the first instance of a technology that has been able to provide an insight into the copy number of a specific gene locus in hybrid sugarcane. The identification of specific and numerous haplotypes/alleles present in a genotype by pyrophosphate sequencing or alternative techniques ultimately will provide the basis for identifying associations between specific alleles and phenotype and between allele dosage and phenotype in sugarcane.
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Affiliation(s)
- Giovanni M Cordeiro
- Centre for Plant Conservation Genetics, Southern Cross University, PO Box 157, Lismore 2480, Australia.
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14
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Microspore gene expression associated with cytoplasmic male sterility and fertility restoration in sorghum. ACTA ACUST UNITED AC 2006. [DOI: 10.1007/s00497-005-0019-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Carvalho CHS, Boddu J, Zehr UB, Axtell JD, Pedersen JF, Chopra S. Genietic and molecular characterization of Candystripel transposition events in sorghum. Genetica 2005; 124:201-12. [PMID: 16134333 DOI: 10.1007/s10709-005-2268-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In sorghum, the Candystripe1 (Cs1) transposable element causes a variegated pericarp phenotype due to its excision activity from the yl (yellow seed1) locus. The Y1 is a transcription regulator which is required for the biosynthesis of red 3-deoxyflavonoid pigments. Somatic variability in the transposition behavior of Cs1 was observed via biochemical analysis of 3-deoxyflavonoids in the leaf tissues of the Y1-cs alleles. Using somatic excisions of Cs1 as a tool, we establish that the Cs1 is active in young seedlings and the y1 locus is also functional in these tissues. Several somatic and germinal excision events were characterized and sequence analysis of independent events predominantly showed 2-bp footprints. Further, with the goal of ur.derstanding the properties of Cs1 that would facilitate the development of a transposon tagging system in sorghum, germinal excisions of Cs1 from y1 were used as a marker. Transposition of Cs1 was followed by characterization of putative insertion events. Genetic linkage between mutant phenotypes and the cosegregating restriction fragments of Cs1 provided additional evidence that Cs1 is an active transposable element in sorghum.
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16
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Pratt LH, Liang C, Shah M, Sun F, Wang H, Reid SP, Gingle AR, Paterson AH, Wing R, Dean R, Klein R, Nguyen HT, Ma HM, Zhao X, Morishige DT, Mullet JE, Cordonnier-Pratt MM. Sorghum expressed sequence tags identify signature genes for drought, pathogenesis, and skotomorphogenesis from a milestone set of 16,801 unique transcripts. PLANT PHYSIOLOGY 2005; 139:869-84. [PMID: 16169961 PMCID: PMC1256002 DOI: 10.1104/pp.105.066134] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Revised: 07/20/2005] [Accepted: 07/26/2005] [Indexed: 05/04/2023]
Abstract
Improved knowledge of the sorghum transcriptome will enhance basic understanding of how plants respond to stresses and serve as a source of genes of value to agriculture. Toward this goal, Sorghum bicolor L. Moench cDNA libraries were prepared from light- and dark-grown seedlings, drought-stressed plants, Colletotrichum-infected seedlings and plants, ovaries, embryos, and immature panicles. Other libraries were prepared with meristems from Sorghum propinquum (Kunth) Hitchc. that had been photoperiodically induced to flower, and with rhizomes from S. propinquum and johnsongrass (Sorghum halepense L. Pers.). A total of 117,682 expressed sequence tags (ESTs) were obtained representing both 3' and 5' sequences from about half that number of cDNA clones. A total of 16,801 unique transcripts, representing tentative UniScripts (TUs), were identified from 55,783 3' ESTs. Of these TUs, 9,032 are represented by two or more ESTs. Collectively, these libraries were predicted to contain a total of approximately 31,000 TUs. Individual libraries, however, were predicted to contain no more than about 6,000 to 9,000, with the exception of light-grown seedlings, which yielded an estimate of close to 13,000. In addition, each library exhibits about the same level of complexity with respect to both the number of TUs preferentially expressed in that library and the frequency with which two or more ESTs is found in only that library. These results indicate that the sorghum genome is expressed in highly selective fashion in the individual organs and in response to the environmental conditions surveyed here. Close to 2,000 differentially expressed TUs were identified among the cDNA libraries examined, of which 775 were differentially expressed at a confidence level of 98%. From these 775 TUs, signature genes were identified defining drought, Colletotrichum infection, skotomorphogenesis (etiolation), ovary, immature panicle, and embryo.
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Affiliation(s)
- Lee H Pratt
- Department of Plant Biology, University of Georgia, Athens, 30602, USA.
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17
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Klein RR, Klein PE, Mullet JE, Minx P, Rooney WL, Schertz KF. Fertility restorer locus Rf1 [corrected] of sorghum (Sorghum bicolor L.) encodes a pentatricopeptide repeat protein not present in the colinear region of rice chromosome 12. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2005; 111:994-1012. [PMID: 16078015 DOI: 10.1007/s00122-005-2011-y] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2004] [Accepted: 03/17/2005] [Indexed: 05/03/2023]
Abstract
With an aim to clone the sorghum fertility restorer gene Rf1, a high-resolution genetic and physical map of the locus was constructed. The Rf1 locus was resolved to a 32-kb region spanning four open reading frames: a plasma membrane Ca(2+)-ATPase, a cyclin D-1, an unknown protein, and a pentatricopeptide repeat (PPR13) gene family member. An approximately 19-kb region spanning the cyclin D-1 and unknown protein genes was completely conserved between sterile and fertile plants as was the sequence spanning the coding region of the Ca(2+)-ATPase. In contrast, 19 sequence polymorphisms were located in an approximately 7-kb region spanning PPR13, and all markers cosegregated with the fertility restoration phenotype. PPR13 was predicted to encode a mitochondrial-targeted protein containing a single exon with 14 PPR repeats, and the protein is classified as an E-type PPR subfamily member. To permit sequence-based comparison of the sorghum and rice genomes in the Rf1 region, 0.53 Mb of sorghum chromosome 8 was sequenced and compared to the colinear region of rice chromosome 12. Genome comparison revealed a mosaic pattern of colinearity with an approximately 275-kb gene-poor region with little gene conservation and an adjacent, approximately 245-kb gene-rice region that is more highly conserved between rice and sorghum. Despite being located in a region of high gene conservation, sorghum PPR13 was not located in a colinear position on rice chromosome 12. The present results suggest that sorghum PPR13 represents a potential candidate for the sorghum Rf1 gene, and its presence in the sorghum genome indicates a single gene transposition event subsequent to the divergence of rice and sorghum ancestors.
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Affiliation(s)
- R R Klein
- Southern Plains Agricultural Research Center, USDA-ARS, College Station, TX 77845, USA.
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18
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Hamblin MT, Salas Fernandez MG, Casa AM, Mitchell SE, Paterson AH, Kresovich S. Equilibrium processes cannot explain high levels of short- and medium-range linkage disequilibrium in the domesticated grass Sorghum bicolor. Genetics 2005; 171:1247-56. [PMID: 16157678 PMCID: PMC1456844 DOI: 10.1534/genetics.105.041566] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Patterns of linkage disequilibrium (LD) are of interest because they provide evidence of both equilibrium (e.g., mating system or long-term population structure) and nonequilibrium (e.g., demographic or selective) processes, as well as because of their importance in strategies for identifying the genetic basis of complex phenotypes. We report patterns of short and medium range (up to 100 kb) LD in six unlinked genomic regions in the partially selfing domesticated grass, Sorghum bicolor. The extent of allelic associations in S. bicolor, as assessed by pairwise measures of LD, is higher than in maize but lower than in Arabidopsis, in qualitative agreement with expectations based on mating system. Quantitative analyses of the population recombination parameter, rho, however, based on empirical estimates of rates of recombination, mutation, and self-pollination, show that LD is more extensive than expected under a neutral equilibrium model. The disparity between rho and the population mutation parameter, , is similar to that observed in other species whose population history appears to be complex. From a practical standpoint, these results suggest that S. bicolor is well suited for association studies using reasonable numbers of markers, since LD typically extends at least several kilobases but has largely decayed by 15 kb.
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Affiliation(s)
- Martha T Hamblin
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853, USA
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19
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Buchanan CD, Lim S, Salzman RA, Kagiampakis I, Morishige DT, Weers BD, Klein RR, Pratt LH, Cordonnier-Pratt MM, Klein PE, Mullet JE. Sorghum bicolor's transcriptome response to dehydration, high salinity and ABA. PLANT MOLECULAR BIOLOGY 2005; 58:699-720. [PMID: 16158244 DOI: 10.1007/s11103-005-7876-2] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Accepted: 05/25/2005] [Indexed: 05/04/2023]
Abstract
Genome wide changes in gene expression were monitored in the drought tolerant C4 cereal Sorghum bicolor, following exposure of seedlings to high salinity (150 mM NaCl), osmotic stress (20% polyethylene glycol) or abscisic acid (125 microM ABA). A sorghum cDNA microarray providing data on 12,982 unique gene clusters was used to examine gene expression in roots and shoots at 3- and 27-h post-treatment. Expression of approximately 2200 genes, including 174 genes with currently unknown functions, of which a subset appear unique to monocots and/or sorghum, was altered in response to dehydration, high salinity or ABA. The modulated sorghum genes had homology to proteins involved in regulation, growth, transport, membrane/protein turnover/repair, metabolism, dehydration protection, reactive oxygen scavenging, and plant defense. Real-time PCR was used to quantify changes in relative mRNA abundance for 333 genes that responded to ABA, NaCl or osmotic stress. Osmotic stress inducible sorghum genes identified for the first time included a beta-expansin expressed in shoots, actin depolymerization factor, inositol-3-phosphate synthase, a non-C4 NADP-malic enzyme, oleosin, and three genes homologous to 9-cis-epoxycarotenoid dioxygenase that may be involved in ABA biosynthesis. Analysis of response profiles demonstrated the existence of a complex gene regulatory network that differentially modulates gene expression in a tissue- and kinetic-specific manner in response to ABA, high salinity and water deficit. Modulation of genes involved in signal transduction, chromatin structure, transcription, translation and RNA metabolism contributes to sorghum's overlapping but nonetheless distinct responses to ABA, high salinity, and osmotic stress. Overall, this study provides a foundation of information on sorghum's osmotic stress responsive gene complement that will accelerate follow up biochemical, QTL and comparative studies.
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Affiliation(s)
- Christina D Buchanan
- Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX, 77843, USA
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Kochian LV, Piñeros MA, Hoekenga OA. The Physiology, Genetics and Molecular Biology of Plant Aluminum Resistance and Toxicity. PLANT AND SOIL 2005; 274:175-195. [PMID: 0 DOI: 10.1007/s11104-004-1158-7] [Citation(s) in RCA: 292] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
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21
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Kochian LV, Piñeros MA, Hoekenga OA. The physiology, genetics and molecular biology of plant aluminum resistance and toxicity. ACTA ACUST UNITED AC 2005. [DOI: 10.1007/1-4020-4099-7_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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22
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Buchanan CD, Klein PE, Mullet JE. Phylogenetic analysis of 5'-noncoding regions from the ABA-responsive rab16/17 gene family of sorghum, maize and rice provides insight into the composition, organization and function of cis-regulatory modules. Genetics 2004; 168:1639-54. [PMID: 15579713 PMCID: PMC1448771 DOI: 10.1534/genetics.104.030346] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2004] [Accepted: 07/16/2004] [Indexed: 11/18/2022] Open
Abstract
Phylogenetic analysis of sequences from gene families and homologous genes from species of varying divergence can be used to identify conserved noncoding regulatory elements. In this study, phylogenetic analysis of 5'-noncoding sequences was optimized using rab17, a well-characterized ABA-responsive gene from maize, and five additional rab16/17 homologs from sorghum and rice. Conserved 5'-noncoding sequences among the maize, sorghum, and rice rab16/17 homologs were identified with the aid of the software program FootPrinter and by screening for known transcription-factor-binding sites. Searches for 7 of 8 (7/8)bp sequence matches within aligned 5'-noncoding segments of the rab genes identified many of the cis-elements previously characterized by biochemical analysis in maize rab17 plus several additional putative regulatory elements. Differences in the composition of conserved noncoding sequences among rab16/17 genes were related to variation in rab gene mRNA levels in different tissues and to response to ABA treatment using qRT-PCR. Absence of a GRA-like element in the promoter of sorghum dhn2 relative to maize rab17 was correlated with an approximately 85-fold reduction of dhn2 RNA in sorghum shoots. Overall, we conclude that phylogenetic analysis of gene families among rice, sorghum, and maize will help identify regulatory sequences in the noncoding regions of genes and contribute to our understanding of grass gene regulatory networks.
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Affiliation(s)
- Christina D Buchanan
- Institute for Plant Genomics and Biotechnology, Texas A and M University, College Station, Texas 77843, USA
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23
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Gupta PK, Rustgi S. Molecular markers from the transcribed/expressed region of the genome in higher plants. Funct Integr Genomics 2004; 4:139-62. [PMID: 15095058 DOI: 10.1007/s10142-004-0107-0] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2003] [Revised: 12/16/2003] [Accepted: 12/19/2003] [Indexed: 10/26/2022]
Abstract
In recent years, molecular marker technology in higher plants has witnessed a shift from the so-called random DNA markers (RDMs), developed in the past arbitrarily from genomic DNA and cDNA, to the molecular markers representing the transcriptome and the other coding sequences. These markers have been described as gene targeted markers (GTMs). Another specific class of markers includes the so-called functional markers (FMs), which are supposed to have a cause and effect relationship with the traits of interest. In this review, we first describe the development of these markers representing the transcriptome or genes per se; we then discuss the uses of these markers in some detail and finally add a note on the future directions of research and the implications of the wider application of these markers in crop improvement programmes. Using suitable examples, we describe markers of different classes derived from cDNA clones, expressed sequence tags (ESTs), gene sequences and the unique (coding) sequences obtained through methyl filtration or genome normalization (high C(0) t fraction) from gDNA libraries. While we briefly describe RFLPs, SSRs, AFLPs and SNPs developed from the transcriptome (cDNA clones and EST databases), we have discussed in more detail some of the novel markers developed from the transcriptome and specific genes. These novel markers include expressed sequence tag polymorphisms (ESTPs), conserved orthologue set (COS) markers, amplified consensus genetic markers (ACGMs), gene specific tags (GSTs), resistance gene analogues (RGAs) and exon-retrotransposon amplification polymorphism (ERAP). Uses of these markers have been discussed in some detail under the following headings: development of transcript and functional maps, estimations of genetic diversity, marker-assisted selection (MAS), candidate-gene (CG) approach and map-based cloning, genetical genomics and identification of eQTLs, study of genome organization and taxonomic and phylogenetic studies. At the end, we also append a list of websites relevant to further studies on the transcriptome. For want of space, considerable information including voluminous data in the form of 12 tables, and a long list of references cited in these tables, has been placed on the Internet as electronic supplementary material (ESM), which the readers may find useful.
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Affiliation(s)
- P K Gupta
- Molecular Biology Laboratory, Department of Genetics and Plant Breeding, Ch. Charan Singh University, 250 004, Meerut, India.
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Bhargava S, Paranjpe S. Genotypic variation in the photosynthetic competence of Sorghum bicolor seedlings subjected to polyethylene glycol-mediated drought stress. JOURNAL OF PLANT PHYSIOLOGY 2004; 161:125-129. [PMID: 15002674 DOI: 10.1078/0176-1617-01126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Eleven varieties of Sorghum bicolor, subjected to PEG-mediated drought stress were compared for their photosynthetic performance. The varieties differed in their relative water content over a range of PEG concentrations (0-25%). CO2 assimilation, stomatal conductance and the quantum yield of PSII electron transport decreased with increasing PEG concentrations in all varieties. However the intercellular CO2 concentration showed a nonlinear PEG concentration-dependent change. At lower PEG concentrations there was a decrease in the levels of intercellular CO2 concentration in all varieties that could be attributed to stomatal closure. At higher PEG concentrations, some varieties showed an increase in the intercellular CO2 concentration, indicating an inhibition of photosynthetic activity due to non-stomatal effects, while others did not. It was seen that the varieties differed in the stress thresholds at which stomatal and metabolic limitations to photosynthesis occur. These differences in the photosynthetic adaptation of Sorghum varieties could be useful in identifying genotypes showing large differences in photosynthetic adaptation, which could be useful in mapping photosynthetic traits for drought stress tolerance.
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Kochian LV, Hoekenga OA, Pineros MA. How do crop plants tolerate acid soils? Mechanisms of aluminum tolerance and phosphorous efficiency. ANNUAL REVIEW OF PLANT BIOLOGY 2004; 55:459-93. [PMID: 15377228 DOI: 10.1146/annurev.arplant.55.031903.141655] [Citation(s) in RCA: 723] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Acid soils significantly limit crop production worldwide because approximately 50% of the world's potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring tolerance to acid soil stress has been a focus of intense research interest over the past decade. The primary limitations on acid soils are toxic levels of aluminum (Al) and manganese (Mn), as well as suboptimal levels of phosphorous (P). This review examines our current understanding of the physiological, genetic, and molecular basis for crop Al tolerance, as well as reviews the emerging area of P efficiency, which involves the genetically based ability of some crop genotypes to tolerate P deficiency stress on acid soils. These are interesting times for this field because researchers are on the verge of identifying some of the genes that confer Al tolerance in crop plants; these discoveries will open up new avenues of molecular/physiological inquiry that should greatly advance our understanding of these tolerance mechanisms. Additionally, these breakthroughs will provide new molecular resources for improving crop Al tolerance via both molecular-assisted breeding and biotechnology.
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Affiliation(s)
- Leon V Kochian
- U.S. Plant, Soil, and Nutrition Laboratory, USDA-ARS, Cornell University, Ithaca, New York 14853, USA.
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26
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Multani DS, Briggs SP, Chamberlin MA, Blakeslee JJ, Murphy AS, Johal GS. Loss of an MDR transporter in compact stalks of maize br2 and sorghum dw3 mutants. Science 2003; 302:81-4. [PMID: 14526073 DOI: 10.1126/science.1086072] [Citation(s) in RCA: 302] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Agriculturally advantageous reduction in plant height is usually achieved by blocking the action or production of gibberellins. Here, we describe a different dwarfing mechanism found in maize brachytic2 (br2) mutants characterized by compact lower stalk internodes. The height reduction in these plants results from the loss of a P-glycoprotein that modulates polar auxin transport in the maize stalk. The sorghum ortholog of br2 is dwarf3 (dw3), an unstable mutant of long-standing commercial interest and concern. A direct duplication within the dw3 gene is responsible for its mutant nature and also for its instability, because it facilitates unequal crossing-over at the locus.
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Affiliation(s)
- Dilbag S Multani
- Pioneer Hi-Bred International, 7250 Northwest 62nd Avenue, Johnston, IA 50131, USA
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27
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Current Awareness on Comparative and Functional Genomics. Comp Funct Genomics 2002. [PMCID: PMC2448432 DOI: 10.1002/cfg.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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