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Shikha K, Madhumal Thayil V, Shahi JP, Zaidi PH, Seetharam K, Nair SK, Singh R, Tosh G, Singamsetti A, Singh S, Sinha B. Genomic-regions associated with cold stress tolerance in Asia-adapted tropical maize germplasm. Sci Rep 2023; 13:6297. [PMID: 37072497 PMCID: PMC10113201 DOI: 10.1038/s41598-023-33250-8] [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] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 04/10/2023] [Indexed: 05/03/2023] Open
Abstract
Maize is gaining impetus in non-traditional and non-conventional seasons such as off-season, primarily due to higher demand and economic returns. Maize varieties directed for growing in the winter season of South Asia must have cold resilience as an important trait due to the low prevailing temperatures and frequent cold snaps observed during this season in most parts of the lowland tropics of Asia. The current study involved screening of a panel of advanced tropically adapted maize lines to cold stress during vegetative and flowering stage under field conditions. A suite of significant genomic loci (28) associated with grain yield along and agronomic traits such as flowering (15) and plant height (6) under cold stress environments. The haplotype regression revealed 6 significant haplotype blocks for grain yield under cold stress across the test environments. Haplotype blocks particularly on chromosomes 5 (bin5.07), 6 (bin6.02), and 9 (9.03) co-located to regions/bins that have been identified to contain candidate genes involved in membrane transport system that would provide essential tolerance to the plant. The regions on chromosome 1 (bin1.04), 2 (bin 2.07), 3 (bin 3.05-3.06), 5 (bin5.03), 8 (bin8.05-8.06) also harboured significant SNPs for the other agronomic traits. In addition, the study also looked at the plausibility of identifying tropically adapted maize lines from the working germplasm with cold resilience across growth stages and identified four lines that could be used as breeding starts in the tropical maize breeding pipelines.
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Affiliation(s)
- Kumari Shikha
- Department of Genetics and Plant Breeding, Banaras Hindu University (BHU), Varanasi, India
| | - Vinayan Madhumal Thayil
- International Maize and Wheat Improvement Centre (CIMMYT), ICRISAT Campus, Patancheru, Telangana, India.
| | - J P Shahi
- Department of Genetics and Plant Breeding, Banaras Hindu University (BHU), Varanasi, India
| | - P H Zaidi
- International Maize and Wheat Improvement Centre (CIMMYT), ICRISAT Campus, Patancheru, Telangana, India
| | - Kaliyamoorthy Seetharam
- International Maize and Wheat Improvement Centre (CIMMYT), ICRISAT Campus, Patancheru, Telangana, India
| | - Sudha K Nair
- International Maize and Wheat Improvement Centre (CIMMYT), ICRISAT Campus, Patancheru, Telangana, India
| | - Raju Singh
- Borlaug Institute for South Asia (BISA), Ludhiana, Punjab, India
| | - Garg Tosh
- Punjab Agricultural University (PAU), Ludhiana, India
| | - Ashok Singamsetti
- Department of Genetics and Plant Breeding, Banaras Hindu University (BHU), Varanasi, India
| | - Saurabh Singh
- Department of Genetics and Plant Breeding, Banaras Hindu University (BHU), Varanasi, India
| | - B Sinha
- Department of Genetics and Plant Breeding, Banaras Hindu University (BHU), Varanasi, India
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Qu J, Chassaigne-Ricciulli AA, Fu F, Yu H, Dreher K, Nair SK, Gowda M, Beyene Y, Makumbi D, Dhliwayo T, Vicente FS, Olsen M, Prasanna BM, Li W, Zhang X. Low-Density Reference Fingerprinting SNP Dataset of CIMMYT Maize Lines for Quality Control and Genetic Diversity Analyses. Plants (Basel) 2022; 11:3092. [PMID: 36432819 PMCID: PMC9697014 DOI: 10.3390/plants11223092] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 10/31/2022] [Accepted: 11/10/2022] [Indexed: 06/16/2023]
Abstract
CIMMYT maize lines (CMLs), which represent the tropical maize germplasm, are freely available worldwide. All currently released 615 CMLs and fourteen temperate maize inbred lines were genotyped with 180 kompetitive allele-specific PCR single nucleotide polymorphisms to develop a reference fingerprinting SNP dataset that can be used to perform quality control (QC) and genetic diversity analyses. The QC analysis identified 25 CMLs with purity, identity, or mislabeling issues. Further field observation, purification, and re-genotyping of these CMLs are required. The reference fingerprinting SNP dataset was developed for all of the currently released CMLs with 152 high-quality SNPs. The results of principal component analysis and average genetic distances between subgroups showed a clear genetic divergence between temperate and tropical maize, whereas the three tropical subgroups partially overlapped with one another. More than 99% of the pairs of CMLs had genetic distances greater than 0.30, showing their high genetic diversity, and most CMLs are distantly related. The heterotic patterns, estimated with the molecular markers, are consistent with those estimated using pedigree information in two major maize breeding programs at CIMMYT. These research findings are helpful for ensuring the regeneration and distribution of the true CMLs, via QC analysis, and for facilitating the effective utilization of the CMLs, globally.
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Affiliation(s)
- Jingtao Qu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China
- International Maize and Wheat Improvement Center (CIMMYT), El Batan, Texcoco 56237, Mexico
| | | | - Fengling Fu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Haoqiang Yu
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Kate Dreher
- International Maize and Wheat Improvement Center (CIMMYT), El Batan, Texcoco 56237, Mexico
| | - Sudha K. Nair
- Asia Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Hyderabad 502324, Telangana, India
| | - Manje Gowda
- International Maize and Wheat Improvement Center (CIMMYT), Village Market, P.O. Box 1041, Nairobi 00621, Kenya
| | - Yoseph Beyene
- International Maize and Wheat Improvement Center (CIMMYT), Village Market, P.O. Box 1041, Nairobi 00621, Kenya
| | - Dan Makumbi
- International Maize and Wheat Improvement Center (CIMMYT), Village Market, P.O. Box 1041, Nairobi 00621, Kenya
| | - Thanda Dhliwayo
- International Maize and Wheat Improvement Center (CIMMYT), El Batan, Texcoco 56237, Mexico
| | - Felix San Vicente
- International Maize and Wheat Improvement Center (CIMMYT), El Batan, Texcoco 56237, Mexico
| | - Michael Olsen
- International Maize and Wheat Improvement Center (CIMMYT), Village Market, P.O. Box 1041, Nairobi 00621, Kenya
| | - Boddupalli M. Prasanna
- International Maize and Wheat Improvement Center (CIMMYT), Village Market, P.O. Box 1041, Nairobi 00621, Kenya
| | - Wanchen Li
- Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China
| | - Xuecai Zhang
- International Maize and Wheat Improvement Center (CIMMYT), El Batan, Texcoco 56237, Mexico
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Jadhav KP, Saykhedkar GR, Tamilarasi PM, Devasree S, Ranjani RV, Sarankumar C, Bharathi P, Karthikeyan A, Arulselvi S, Vijayagowri E, Ganesan KN, Paranidharan V, Nair SK, Babu R, Ramalingam J, Raveendran M, Senthil N. GBS-Based SNP Map Pinpoints the QTL Associated With Sorghum Downy Mildew Resistance in Maize (Zea mays L.). Front Genet 2022; 13:890133. [PMID: 35937985 PMCID: PMC9348272 DOI: 10.3389/fgene.2022.890133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 06/13/2022] [Indexed: 12/04/2022] Open
Abstract
Sorghum downy mildew (SDM), caused by the biotrophic fungi Peronosclerospora sorghi, threatens maize production worldwide, including India. To identify quantitative trait loci (QTL) associated with resistance to SDM, we used a recombinant inbred line (RIL) population derived from a cross between resistant inbred line UMI936 (w) and susceptible inbred line UMI79. The RIL population was phenotyped for SDM resistance in three environments [E1-field (Coimbatore), E2-greenhouse (Coimbatore), and E3-field (Mandya)] and also utilized to construct the genetic linkage map by genotyping by sequencing (GBS) approach. The map comprises 1516 SNP markers in 10 linkage groups (LGs) with a total length of 6924.7 cM and an average marker distance of 4.57 cM. The QTL analysis with the phenotype and marker data detected nine QTL on chromosome 1, 2, 3, 5, 6, and 7 across three environments. Of these, QTL namely qDMR1.2, qDMR3.1, qDMR5.1, and qDMR6.1 were notable due to their high phenotypic variance. qDMR3.1 from chromosome 3 was detected in more than one environment (E1 and E2), explaining the 10.3% and 13.1% phenotypic variance. Three QTL, qDMR1.2, qDMR5.1, and qDMR6.1 from chromosomes 1, 5, and 6 were identified in either E1 or E3, explaining 15.2%–18% phenotypic variance. Moreover, genome mining on three QTL (qDMR3.1, qDMR5.1, and qDMR6.1) reveals the putative candidate genes related to SDM resistance. The information generated in this study will be helpful for map-based cloning and marker-assisted selection in maize breeding programs.
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Affiliation(s)
- Kashmiri Prakash Jadhav
- Department of Plant Biotechnology, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
| | - Gajanan R. Saykhedkar
- Asian Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, India
| | | | - Subramani Devasree
- Department of Millets, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore, India
| | - Rajagopalan Veera Ranjani
- Department of Plant Biotechnology, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
| | - Chandran Sarankumar
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Pukalenthy Bharathi
- Department of Plant Breeding and Genetics, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Adhimoolam Karthikeyan
- Department of Biotechnology, Centre of Innovation, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
| | - Soosai Arulselvi
- Agricultural College and Research Institute, Thanjavur, Tamil Nadu Agricultural University, Thanjavur, India
| | - Esvaran Vijayagowri
- Department of Plant Biotechnology, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
| | - Kalipatty Nalliappan Ganesan
- Department of Forage Crops, Centre for Plant Breeding and Genetics, Tamil Nadu Agricultural University, Coimbatore, India
| | - Vaikuntavasan Paranidharan
- Department of Plant Pathology, Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore, India
| | - Sudha K. Nair
- Asian Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, India
| | - Raman Babu
- Corteva Agrisciences, Multi Crop Research Centre, Hyderabad, India
| | - Jegadeesan Ramalingam
- Department of Plant Biotechnology, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
| | - Muthurajan Raveendran
- Department of Plant Biotechnology, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
| | - Natesan Senthil
- Department of Biotechnology, Centre of Innovation, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India
- Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore, India
- *Correspondence: Natesan Senthil,
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Rashid Z, Kaur H, Babu V, Singh PK, Harlapur SI, Nair SK. Identification and Validation of Genomic Regions Associated With Charcoal Rot Resistance in Tropical Maize by Genome-Wide Association and Linkage Mapping. Front Plant Sci 2021; 12:726767. [PMID: 34691105 PMCID: PMC8531636 DOI: 10.3389/fpls.2021.726767] [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] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 08/30/2021] [Indexed: 06/01/2023]
Abstract
Charcoal rot is a post-flowering stalk rot (PFSR) disease of maize caused by the fungal pathogen, Macrophomina phaseolina. It is a serious concern for smallholder maize cultivation, due to significant yield loss and plant lodging at harvest, and this disease is expected to surge with climate change effects like drought and high soil temperature. For identification and validation of genomic variants associated with charcoal rot resistance, a genome-wide association study (GWAS) was conducted on CIMMYT Asia association mapping panel comprising 396 tropical-adapted lines, especially to Asian environments. The panel was phenotyped for disease severity across two locations with high disease prevalence in India. A subset of 296,497 high-quality SNPs filtered from genotyping by sequencing was correcting for population structure and kinship matrices for single locus mixed linear model (MLM) of GWAS analysis. A total of 19 SNPs were identified to be associated with charcoal rot resistance with P-value ranging from 5.88 × 10-06 to 4.80 × 10-05. Haplotype regression analysis identified 21 significant haplotypes for the trait with Bonferroni corrected P ≤ 0.05. For validating the associated variants and identifying novel QTLs, QTL mapping was conducted using two F2:3 populations. Two QTLs with overlapping physical intervals, qMSR6 and qFMSR6 on chromosome 6, identified from two different mapping populations and contributed by two different resistant parents, were co-located with the SNPs and haplotypes identified at 103.51 Mb on chromosome 6. Similarly, several SNPs/haplotypes identified on chromosomes 3, 6 and 8 were also found to be physically co-located within QTL intervals detected in one of the two mapping populations. The study also noted that several SNPs/haplotypes for resistance to charcoal rot were located within physical intervals of previously reported QTLs for Gibberella stalk rot resistance, which opens up a new possibility for common disease resistance mechanisms for multiple stalk rots.
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Affiliation(s)
- Zerka Rashid
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Hyderabad, India
| | - Harleen Kaur
- Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, India
| | - Veerendra Babu
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Hyderabad, India
| | - Pradeep Kumar Singh
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Hyderabad, India
| | | | - Sudha K. Nair
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Hyderabad, India
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Prasanna BM, Cairns JE, Zaidi PH, Beyene Y, Makumbi D, Gowda M, Magorokosho C, Zaman-Allah M, Olsen M, Das A, Worku M, Gethi J, Vivek BS, Nair SK, Rashid Z, Vinayan MT, Issa AB, San Vicente F, Dhliwayo T, Zhang X. Beat the stress: breeding for climate resilience in maize for the tropical rainfed environments. Theor Appl Genet 2021; 134:1729-1752. [PMID: 33594449 PMCID: PMC7885763 DOI: 10.1007/s00122-021-03773-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 01/09/2021] [Indexed: 05/03/2023]
Abstract
Intensive public sector breeding efforts and public-private partnerships have led to the increase in genetic gains, and deployment of elite climate-resilient maize cultivars for the stress-prone environments in the tropics. Maize (Zea mays L.) plays a critical role in ensuring food and nutritional security, and livelihoods of millions of resource-constrained smallholders. However, maize yields in the tropical rainfed environments are now increasingly vulnerable to various climate-induced stresses, especially drought, heat, waterlogging, salinity, cold, diseases, and insect pests, which often come in combinations to severely impact maize crops. The International Maize and Wheat Improvement Center (CIMMYT), in partnership with several public and private sector institutions, has been intensively engaged over the last four decades in breeding elite tropical maize germplasm with tolerance to key abiotic and biotic stresses, using an extensive managed stress screening network and on-farm testing system. This has led to the successful development and deployment of an array of elite stress-tolerant maize cultivars across sub-Saharan Africa, Asia, and Latin America. Further increasing genetic gains in the tropical maize breeding programs demands judicious integration of doubled haploidy, high-throughput and precise phenotyping, genomics-assisted breeding, breeding data management, and more effective decision support tools. Multi-institutional efforts, especially public-private alliances, are key to ensure that the improved maize varieties effectively reach the climate-vulnerable farming communities in the tropics, including accelerated replacement of old/obsolete varieties.
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Affiliation(s)
- Boddupalli M Prasanna
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya.
| | | | - P H Zaidi
- CIMMYT, ICRISAT Campus, Patancheru, Greater Hyderabad, Telangana, India
| | - Yoseph Beyene
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | - Dan Makumbi
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | - Manje Gowda
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | | | | | - Mike Olsen
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | - Aparna Das
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | - Mosisa Worku
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | | | - B S Vivek
- CIMMYT, ICRISAT Campus, Patancheru, Greater Hyderabad, Telangana, India
| | - Sudha K Nair
- CIMMYT, ICRISAT Campus, Patancheru, Greater Hyderabad, Telangana, India
| | - Zerka Rashid
- CIMMYT, ICRISAT Campus, Patancheru, Greater Hyderabad, Telangana, India
| | - M T Vinayan
- CIMMYT, ICRISAT Campus, Patancheru, Greater Hyderabad, Telangana, India
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Kibe M, Nair SK, Das B, Bright JM, Makumbi D, Kinyua J, Suresh LM, Beyene Y, Olsen MS, Prasanna BM, Gowda M. Genetic Dissection of Resistance to Gray Leaf Spot by Combining Genome-Wide Association, Linkage Mapping, and Genomic Prediction in Tropical Maize Germplasm. Front Plant Sci 2020; 11:572027. [PMID: 33224163 PMCID: PMC7667048 DOI: 10.3389/fpls.2020.572027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 09/29/2020] [Indexed: 05/05/2023]
Abstract
Gray leaf spot (GLS) is one of the major maize foliar diseases in sub-Saharan Africa. Resistance to GLS is controlled by multiple genes with additive effect and is influenced by both genotype and environment. The objectives of the study were to dissect the genetic architecture of GLS resistance through linkage mapping and genome-wide association study (GWAS) and assessing the potential of genomic prediction (GP). We used both biparental populations and an association mapping panel of 410 diverse tropical/subtropical inbred lines that were genotyped using genotype by sequencing. Phenotypic evaluation in two to four environments revealed significant genotypic variation and moderate to high heritability estimates ranging from 0.43 to 0.69. GLS was negatively and significantly correlated with grain yield, anthesis date, and plant height. Linkage mapping in five populations revealed 22 quantitative trait loci (QTLs) for GLS resistance. A QTL on chromosome 7 (qGLS7-105) is a major-effect QTL that explained 28.2% of phenotypic variance. Together, all the detected QTLs explained 10.50, 49.70, 23.67, 18.05, and 28.71% of phenotypic variance in doubled haploid (DH) populations 1, 2, 3, and F3 populations 4 and 5, respectively. Joint linkage association mapping across three DH populations detected 14 QTLs that individually explained 0.10-15.7% of phenotypic variance. GWAS revealed 10 significantly (p < 9.5 × 10-6) associated SNPs distributed on chromosomes 1, 2, 6, 7, and 8, which individually explained 6-8% of phenotypic variance. A set of nine candidate genes co-located or in physical proximity to the significant SNPs with roles in plant defense against pathogens were identified. GP revealed low to moderate prediction correlations of 0.39, 0.37, 0.56, 0.30, 0.29, and 0.38 for within IMAS association panel, DH pop1, DH pop2, DH pop3, F3 pop4, and F3 po5, respectively, and accuracy was increased substantially to 0.84 for prediction across three DH populations. When the diversity panel was used as training set to predict the accuracy of GLS resistance in biparental population, there was 20-50% reduction compared to prediction within populations. Overall, the study revealed that resistance to GLS is quantitative in nature and is controlled by many loci with a few major and many minor effects. The SNPs/QTLs identified by GWAS and linkage mapping can be potential targets in improving GLS resistance in breeding programs, while GP further consolidates the development of high GLS-resistant lines by incorporating most of the major- and minor-effect genes.
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Affiliation(s)
- Maguta Kibe
- International Maize and Wheat Improvement Center, Nairobi, Kenya
- Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Sudha K. Nair
- International Maize and Wheat Improvement Center, Hyderabad, India
| | - Biswanath Das
- International Maize and Wheat Improvement Center, Nairobi, Kenya
| | - Jumbo M. Bright
- International Maize and Wheat Improvement Center, Nairobi, Kenya
| | - Dan Makumbi
- International Maize and Wheat Improvement Center, Nairobi, Kenya
| | - Johnson Kinyua
- Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - L. M. Suresh
- International Maize and Wheat Improvement Center, Nairobi, Kenya
| | - Yoseph Beyene
- International Maize and Wheat Improvement Center, Nairobi, Kenya
| | - Michael S. Olsen
- International Maize and Wheat Improvement Center, Nairobi, Kenya
| | | | - Manje Gowda
- International Maize and Wheat Improvement Center, Nairobi, Kenya
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Prasanna BM, Palacios-Rojas N, Hossain F, Muthusamy V, Menkir A, Dhliwayo T, Ndhlela T, San Vicente F, Nair SK, Vivek BS, Zhang X, Olsen M, Fan X. Molecular Breeding for Nutritionally Enriched Maize: Status and Prospects. Front Genet 2020; 10:1392. [PMID: 32153628 PMCID: PMC7046684 DOI: 10.3389/fgene.2019.01392] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [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: 10/31/2019] [Accepted: 12/19/2019] [Indexed: 12/13/2022] Open
Abstract
Maize is a major source of food security and economic development in sub-Saharan Africa (SSA), Latin America, and the Caribbean, and is among the top three cereal crops in Asia. Yet, maize is deficient in certain essential amino acids, vitamins, and minerals. Biofortified maize cultivars enriched with essential minerals and vitamins could be particularly impactful in rural areas with limited access to diversified diet, dietary supplements, and fortified foods. Significant progress has been made in developing, testing, and deploying maize cultivars biofortified with quality protein maize (QPM), provitamin A, and kernel zinc. In this review, we outline the status and prospects of developing nutritionally enriched maize by successfully harnessing conventional and molecular marker-assisted breeding, highlighting the need for intensification of efforts to create greater impacts on malnutrition in maize-consuming populations, especially in the low- and middle-income countries. Molecular marker-assisted selection methods are particularly useful for improving nutritional traits since conventional breeding methods are relatively constrained by the cost and throughput of nutritional trait phenotyping.
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Affiliation(s)
| | | | - Firoz Hossain
- ICAR-Indian Agricultural Research Institute (IARI), New Delhi, India
| | - Vignesh Muthusamy
- ICAR-Indian Agricultural Research Institute (IARI), New Delhi, India
| | - Abebe Menkir
- International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria
| | | | | | | | | | | | | | - Mike Olsen
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
| | - Xingming Fan
- Institute of Crop Sciences, Yunnan Academy of Agricultural Sciences (YAAS), Kunming, China
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Holl EK, Routh JC, Johnston AW, Frazier V, Rice HE, Tracy ET, Nair SK. Immune expression in children with Wilms tumor: a pilot study. J Pediatr Urol 2019; 15:441.e1-441.e8. [PMID: 30981637 DOI: 10.1016/j.jpurol.2019.03.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 03/13/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Given improvements in multimodality therapy, survival among children with Wilms tumor (WT) exceeds 90%. However, 15% of children with favorable histology and 50% of children with anaplastic WT experience recurrence or progression. Of patients with advanced disease, only 50% survive to adulthood. In adult malignancies (including renal tumors), patient survival has improved with the advent of immunotherapy. However, little is known about the immune microenvironment of WT, making the potential role of immunotherapy unclear. OBJECTIVE The objective of the study is to perform an exploratory, descriptive analysis of the immune milieu in WT. STUDY DESIGN Between 2016 and 2017, all pediatric patients with WT, some of whom received neoadjuvant chemotherapy, underwent ex vivo wedge biopsy at the time of nephrectomy. The fresh tumor tissue and peripheral blood samples were analyzed for infiltrating immune infiltrate and effector cells using flow cytometry. Immunohistochemistry was performed for CD4, CD8, and PD-L1 expression. Matched blood samples were obtained for each patient, and circulating immune cells were analyzed by flow cytometry. RESULTS A total of six patients were enrolled. One patient with neuroblastoma was excluded. The remaining five patients included the following: two with unilateral WT (resected before chemotherapy), two with bilateral WT (resected after neoadjuvant chemotherapy), and one with Denys-Drash syndrome, end-stage renal disease, and history of WT in the contralateral kidney. Immune analysis showed that WT were infiltrated by immune cells regardless of chemotherapy status. CD8 and CD4 T cells were present in the tumor tissue and exhibited an activated phenotype. Elevated levels of natural killer (NK) cells were observed in the tumors (Figure). Immune checkpoint PD-L1 was also found expressed in one of the tumors stained. DISCUSSION In this pilot study, it was found that WTs were infiltrated by immune cells (CD45+) both before and after chemotherapy. Elevated levels of NK cells infiltrating the tumor specimens, which were quantitatively increased compared with levels of NK cells circulating in the blood, were noted. T cells, particularly CD4+ and CD8+ T cells, were present in tumor specimens. Tumor-infiltrating CD4 and CD8 T cells displayed an activated phenotype as defined by increased expression of human leukocyte antigen-DR isotype (HLA-DR), programmed cell death protein 1 (PD1), and CD57. Together, these findings suggest that WT microenvironment is immune engaged and may be susceptible to immunotherapy similar to other malignancies. CONCLUSIONS These pilot data suggest an immune-engaged tumor microenvironment is present within WT. This implies that WT may be susceptible to immunotherapy similar to adult renal tumors and other adult malignancies. Follow-up studies are currently underway.
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Affiliation(s)
- E K Holl
- Division of Surgical Sciences, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA.
| | - J C Routh
- Division of Pediatric Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA; Division of Urologic Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - A W Johnston
- Division of Urologic Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - V Frazier
- Division of Surgical Sciences, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - H E Rice
- Division of Pediatric Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA; Division of Urologic Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - E T Tracy
- Division of Pediatric Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA; Division of Urologic Surgery, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - S K Nair
- Division of Surgical Sciences, Dept of Surgery, Duke University School of Medicine, Durham, NC, USA
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Chaikam V, Gowda M, Nair SK, Melchinger AE, Boddupalli PM. Genome-wide association study to identify genomic regions influencing spontaneous fertility in maize haploids. Euphytica 2019; 215:138. [PMID: 31402796 PMCID: PMC6647887 DOI: 10.1007/s10681-019-2459-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 06/29/2019] [Indexed: 05/18/2023]
Abstract
Efficient production and use of doubled haploid lines can greatly accelerate genetic gains in maize breeding programs. One of the critical steps in standard doubled haploid line production is doubling the haploid genome using toxic and costly mitosis-inhibiting chemicals to achieve fertility in haploids. Alternatively, fertility may be spontaneously restored by natural chromosomal doubling, although generally at a rate too low for practical applications in most germplasm. This is the first large-scale genome-wise association study to analyze spontaneous chromosome doubling in haploids derived from tropical maize inbred lines. Induction crosses between tropicalized haploid inducers and 400 inbred lines were made, and the resulting haploid plants were assessed for haploid male fertility which refers to pollen production and haploid fertility which refers to seed production upon self-fertilization. A small number of genotypes were highly fertile and these fertility traits were highly heritable. Agronomic traits like plant height, ear height and tassel branch number were positively correlated with fertility traits. In contrast, haploid induction rate of the source germplasm and plant aspect were not correlated to fertility traits. Several genomic regions and candidate genes were identified that may control spontaneous fertility restoration. Overall, the study revealed the presence of large variation for both haploid male fertility and haploid fertility which can be potentially exploited for improving the efficiency of doubled haploid derivation in tropical maize germplasm.
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Affiliation(s)
- Vijay Chaikam
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O. Box 1041–00621, Nairobi, Kenya
| | - Manje Gowda
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O. Box 1041–00621, Nairobi, Kenya
| | - Sudha K. Nair
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Greater Hyderabad, 502324 India
| | - Albrecht E. Melchinger
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70593 Stuttgart, Germany
| | - Prasanna M. Boddupalli
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF Campus, UN Avenue, Gigiri, P.O. Box 1041–00621, Nairobi, Kenya
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10
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Hindu V, Palacios-Rojas N, Babu R, Suwarno WB, Rashid Z, Usha R, Saykhedkar GR, Nair SK. Identification and validation of genomic regions influencing kernel zinc and iron in maize. Theor Appl Genet 2018; 131:1443-1457. [PMID: 29574570 PMCID: PMC6004279 DOI: 10.1007/s00122-018-3089-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 03/16/2018] [Indexed: 05/19/2023]
Abstract
KEY MESSAGE Genome-wide association study (GWAS) on 923 maize lines and validation in bi-parental populations identified significant genomic regions for kernel-Zinc and-Iron in maize. Bio-fortification of maize with elevated Zinc (Zn) and Iron (Fe) holds considerable promise for alleviating under-nutrition among the world's poor. Bio-fortification through molecular breeding could be an economical strategy for developing nutritious maize, and hence in this study, we adopted GWAS to identify markers associated with high kernel-Zn and Fe in maize and subsequently validated marker-trait associations in independent bi-parental populations. For GWAS, we evaluated a diverse maize association mapping panel of 923 inbred lines across three environments and detected trait associations using high-density Single nucleotide polymorphism (SNPs) obtained through genotyping-by-sequencing. Phenotyping trials of the GWAS panel showed high heritability and moderate correlation between kernel-Zn and Fe concentrations. GWAS revealed a total of 46 SNPs (Zn-20 and Fe-26) significantly associated (P ≤ 5.03 × 10-05) with kernel-Zn and Fe concentrations with some of these associated SNPs located within previously reported QTL intervals for these traits. Three double-haploid (DH) populations were developed using lines identified from the panel that were contrasting for these micronutrients. The DH populations were phenotyped at two environments and were used for validating significant SNPs (P ≤ 1 × 10-03) based on single marker QTL analysis. Based on this analysis, 11 (Zn) and 11 (Fe) SNPs were found to have significant effect on the trait variance (P ≤ 0.01, R2 ≥ 0.05) in at least one bi-parental population. These findings are being pursued in the kernel-Zn and Fe breeding program, and could hold great value in functional analysis and possible cloning of high-value genes for these traits in maize.
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Affiliation(s)
- Vemuri Hindu
- Asia Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Hyderabad, Telangana 502324 India
- Sri Padmavati Mahila Visvavidyalayam (Women’s University), Tirupati, Andhra Pradesh 517502 India
| | - Natalia Palacios-Rojas
- International Maize and Wheat Improvement Center (CIMMYT), Km 45 Carretera Mexico-Veracruz, 56130 Texcoco, Mexico
| | - Raman Babu
- Asia Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Hyderabad, Telangana 502324 India
- Present Address: Multi-Crop Research Center (MCRC), DuPont Pioneer, Hyderabad, Telangana 500078 India
| | - Willy B. Suwarno
- International Maize and Wheat Improvement Center (CIMMYT), Km 45 Carretera Mexico-Veracruz, 56130 Texcoco, Mexico
- Present Address: Department of Agronomy and Horticulture, Faculty of Agriculture, Bogor Agricultural University, Jl. Meranti Kampus IPB Dramaga, Bogor, 16680 Indonesia
| | - Zerka Rashid
- Asia Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Hyderabad, Telangana 502324 India
| | - Rayalcheruvu Usha
- Sri Padmavati Mahila Visvavidyalayam (Women’s University), Tirupati, Andhra Pradesh 517502 India
| | - Gajanan R Saykhedkar
- Asia Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Hyderabad, Telangana 502324 India
- Present Address: Project Director, SPMESM, Dr. Hedgewar Hospital, Aurangabad, Maharashtra 431005 India
| | - Sudha K. Nair
- Asia Regional Maize Program, International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Hyderabad, Telangana 502324 India
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11
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Chaikam V, Nair SK, Martinez L, Lopez LA, Utz HF, Melchinger AE, Boddupalli PM. Marker-Assisted Breeding of Improved Maternal Haploid Inducers in Maize for the Tropical/Subtropical Regions. Front Plant Sci 2018; 9:1527. [PMID: 30405665 PMCID: PMC6201356 DOI: 10.3389/fpls.2018.01527] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Accepted: 09/28/2018] [Indexed: 05/21/2023]
Abstract
For efficient production of doubled haploid (DH) lines in maize, maternal haploid inducer lines with high haploid induction rate (HIR) and good adaptation to the target environments is an important requirement. In this study, we present second-generation Tropically Adapted Inducer Lines (2GTAILs), developed using marker assisted selection (MAS) for qhir1, a QTL with a significant positive effect on HIR from the crosses between elite tropical maize inbreds and first generation Tropically Adapted Inducers Lines (TAILs). Evaluation of 2GTAILs for HIR and agronomic performance in the tropical and subtropical environments indicated superior performance of 2GTAILs over the TAILs for both HIR and agronomic performance, including plant vigor, delayed flowering, grain yield, and resistance to ear rots. One of the new inducers 2GTAIL006 showed an average HIR of 13.1% which is 48.9% higher than the average HIR of the TAILs. Several other 2GTAILs also showed higher HIR compared to the TAILs. While employing MAS for qhir1 QTL, we observed significant influence of the non-inducer parent on the positive effect of qhir1 QTL on HIR. The non-inducer parents that resulted in highest mean HIR in the early generation qhir1+ families also gave rise to highest numbers of candidate inducers, some of which showed transgressive segregation for HIR. The mean HIR of early generation qhir1+ families involving different non-inducer parents can potentially indicate recipient non-inducer parents that can result in progenies with high HIR. Our study also indicated that the HIR associated traits (endosperm abortion rate, embryo abortion rate, and proportion of haploid plants among the inducer plants) can be used to differentiate inducers vs. non-inducers but are not suitable for differentiating inducers with varying levels of haploid induction rates. We propose here an efficient methodology for developing haploid inducer lines combining MAS for qhir1 with HIR associated traits.
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Affiliation(s)
- Vijay Chaikam
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
| | - Sudha K. Nair
- International Maize and Wheat Improvement Center (CIMMYT), Hyderabad, India
| | - Leocadio Martinez
- International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | - Luis Antonio Lopez
- International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
| | - H. Friedrich Utz
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, Stuttgart, Germany
| | - Albrecht E. Melchinger
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, Stuttgart, Germany
| | - Prasanna M. Boddupalli
- International Maize and Wheat Improvement Center (CIMMYT), Nairobi, Kenya
- *Correspondence: Prasanna M. Boddupalli,
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12
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Nair SK, Molenaar W, Melchinger AE, Boddupalli PM, Martinez L, Lopez LA, Chaikam V. Dissection of a major QTL qhir1 conferring maternal haploid induction ability in maize. Theor Appl Genet 2017; 130:1113-1122. [PMID: 28315926 PMCID: PMC5440511 DOI: 10.1007/s00122-017-2873-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Accepted: 02/04/2017] [Indexed: 05/18/2023]
Abstract
Among the qhir11 and qhir12 sub-regions of a major QTL qhir1, only qhir11 has significant effect on maternal haploid induction, segregation distortion and kernel abortion. In vivo haploid induction in maize can be triggered in high frequencies by pollination with special genetic stocks called haploid inducers. Several genetic studies with segregating populations from non-inducer x inducer crosses identified a major QTL, qhir1, on chromosome 1.04 contributing to in vivo haploid induction. A recent Genome Wide Association Study using 51 inducers and 1482 non-inducers also identified two sub-regions within the qhir1 QTL region, named qhir11 and qhir12; qhir12 was proposed to be mandatory for haploid induction because the haplotype of qhir11 was also present in some non-inducers and putative candidate genes coding for DNA and amino acid binding proteins were identified in the qhir12 region. To characterize the effects of each sub-region of qhir1 on haploid induction rate, F2 recombinants segregating for one of the sub-regions and fixed for the other were identified in a cross between CML269 (non-inducer) and a tropicalized haploid inducer TAIL8. To quantify the haploid induction effects of qhir11 and qhir12, selfed progenies of recombinants between these sub-regions were genotyped. F3 plants homozygous for qhir11 and/or qhir12 were identified, and crossed to a ligueless tester to determine their haploid induction rates. The study revealed that only the qhir11 sub-region has a significant effect on haploid induction ability, besides causing significant segregation distortion and kernel abortion, traits that are strongly associated with maternal haploid induction. The results presented in this study can guide fine mapping efforts of qhir1 and in developing new inducers efficiently using marker assisted selection.
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Affiliation(s)
- Sudha K Nair
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT campus, Patancheru, Greater Hyderabad, 502324, India
| | - Willem Molenaar
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70593, Stuttgart, Germany
| | - Albrecht E Melchinger
- Institute of Plant Breeding, Seed Science and Population Genetics, University of Hohenheim, 70593, Stuttgart, Germany
| | - Prasanna M Boddupalli
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya
| | - Leocadio Martinez
- International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600, Mexico, D.F, Mexico
| | - Luis Antonio Lopez
- International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600, Mexico, D.F, Mexico
| | - Vijay Chaikam
- International Maize and Wheat Improvement Center (CIMMYT), ICRAF campus, UN Avenue, Gigiri, P.O.Box 1041-00621, Nairobi, Kenya.
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13
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Pourkheirandish M, Hensel G, Kilian B, Senthil N, Chen G, Sameri M, Azhaguvel P, Sakuma S, Dhanagond S, Sharma R, Mascher M, Himmelbach A, Gottwald S, Nair SK, Tagiri A, Yukuhiro F, Nagamura Y, Kanamori H, Matsumoto T, Willcox G, Middleton CP, Wicker T, Walther A, Waugh R, Fincher GB, Stein N, Kumlehn J, Sato K, Komatsuda T. Evolution of the Grain Dispersal System in Barley. Cell 2015; 162:527-39. [PMID: 26232223 DOI: 10.1016/j.cell.2015.07.002] [Citation(s) in RCA: 173] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 03/13/2015] [Accepted: 06/10/2015] [Indexed: 10/23/2022]
Abstract
About 12,000 years ago in the Near East, humans began the transition from hunter-gathering to agriculture-based societies. Barley was a founder crop in this process, and the most important steps in its domestication were mutations in two adjacent, dominant, and complementary genes, through which grains were retained on the inflorescence at maturity, enabling effective harvesting. Independent recessive mutations in each of these genes caused cell wall thickening in a highly specific grain "disarticulation zone," converting the brittle floral axis (the rachis) of the wild-type into a tough, non-brittle form that promoted grain retention. By tracing the evolutionary history of allelic variation in both genes, we conclude that spatially and temporally independent selections of germplasm with a non-brittle rachis were made during the domestication of barley by farmers in the southern and northern regions of the Levant, actions that made a major contribution to the emergence of early agrarian societies.
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Affiliation(s)
| | - Goetz Hensel
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Benjamin Kilian
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Natesan Senthil
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Guoxiong Chen
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Mohammad Sameri
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Perumal Azhaguvel
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Shun Sakuma
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Sidram Dhanagond
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Rajiv Sharma
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Martin Mascher
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Axel Himmelbach
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Sven Gottwald
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Sudha K Nair
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Akemi Tagiri
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Fumiko Yukuhiro
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Yoshiaki Nagamura
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Hiroyuki Kanamori
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - Takashi Matsumoto
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan
| | - George Willcox
- Archéorient CNRS UMR 5133, Université de Lyon II, Jalés, Berrias 07460, France
| | | | - Thomas Wicker
- Institute of Plant Biology, University of Zürich, 8008 Zürich, Switzerland
| | - Alexander Walther
- Department of Earth Sciences, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Robbie Waugh
- University of Dundee, The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - Geoffrey B Fincher
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus Glen Osmond, SA 5066, Australia
| | - Nils Stein
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Jochen Kumlehn
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, 06466 Stadt Seeland, Germany
| | - Kazuhiro Sato
- Institute of Plant Science and Resources, Okayama University, 710-0046 Kurashiki, Japan
| | - Takao Komatsuda
- National Institute of Agrobiological Sciences, 305-8602 Tsukuba, Japan.
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14
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Nair SK, Babu R, Magorokosho C, Mahuku G, Semagn K, Beyene Y, Das B, Makumbi D, Lava Kumar P, Olsen M, Boddupalli PM. Fine mapping of Msv1, a major QTL for resistance to Maize Streak Virus leads to development of production markers for breeding pipelines. Theor Appl Genet 2015; 128:1839-1854. [PMID: 26081946 DOI: 10.1007/s00122-015-2551-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Accepted: 05/30/2015] [Indexed: 06/04/2023]
Abstract
Msv1 , the major QTL for MSV resistance was delimited to an interval of 0.87 cM on chromosome 1 at 87 Mb and production markers with high prediction accuracy were developed. Maize streak virus (MSV) disease is a devastating disease in the Sub-Saharan Africa (SSA), which causes significant yield loss in maize. Resistance to MSV has previously been mapped to a major QTL (Msv1) on chromosome 1 that is germplasm and environment independent and to several minor loci elsewhere in the genome. In this study, Msv1 was fine-mapped through QTL isogenic recombinant strategy using a large F 2 population of CML206 × CML312 to an interval of 0.87 cM on chromosome 1. Genome-wide association study was conducted in the DTMA (Drought Tolerant Maize for Africa)-Association mapping panel with 278 tropical/sub-tropical breeding lines from CIMMYT using the high-density genotyping-by-sequencing (GBS) markers. This study identified 19 SNPs in the region between 82 and 93 Mb on chromosome 1(B73 RefGen_V2) at a P < 1.00E-04, which coincided with the fine-mapped region of Msv1. Haplotype trend regression identified a haplotype block significantly associated with response to MSV. Three SNPs in this haplotype block at 87 Mb on chromosome 1 had an accuracy of 0.94 in predicting the disease reaction in a collection of breeding lines with known responses to MSV infection. In two biparental populations, selection for resistant Msv1 haplotype demonstrated a reduction of 1.03-1.39 units on a rating scale of 1-5, compared to the susceptible haplotype. High-throughput KASP assays have been developed for these three SNPs to enable routine marker screening in the breeding pipeline for MSV resistance.
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Affiliation(s)
- Sudha K Nair
- International Maize and Wheat Improvement Center (CIMMYT), ICRISAT Campus, Patancheru, Greater Hyderabad, 502324, India,
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15
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Chaikam V, Nair SK, Babu R, Martinez L, Tejomurtula J, Boddupalli PM. Analysis of effectiveness of R1-nj anthocyanin marker for in vivo haploid identification in maize and molecular markers for predicting the inhibition of R1-nj expression. Theor Appl Genet 2015; 128:159-71. [PMID: 25385333 DOI: 10.1007/s00122-014-2419-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Accepted: 10/14/2014] [Indexed: 05/27/2023]
Abstract
R1-nj anthocyanin marker inhibition is highly frequent in tropical maize germplasm considerably affecting efficiency of haploid identification. Molecular markers reliably differentiating germplasm with anthocyanin color inhibitor have been identified in this study. The R1-Navajo (R1-nj) color marker facilitates easy and quick identification of haploid kernels at the seed stage during in vivo haploid induction process in maize. However, the Navajo phenotype can be completely suppressed or poorly expressed in some germplasm, making it impossible or inefficient to identify haploids at the seed stage. In this study, we characterized the expression of R1-nj marker in a large array of tropical/subtropical inbred lines, breeding populations and landraces by crossing with the R1-nj-based tropicalized haploid inducer. There was a high frequency of inhibition of the Navajo phenotype in the maize inbred lines, which are used in tropical breeding programs. Genome-wide association mapping showed that the C1 anthocyanin regulatory locus is the most significant genetic factor influencing inhibition of the Navajo phenotype. Molecular marker assays were designed based on polymorphism in the C1 vs C1-I alleles. Analysis of a set of 714 inbred lines demonstrated that a combination of two gene-specific markers--8 bp C1-I InDel and C1-I SNP--could predict with high accuracy the presence of anthocyanin color inhibition in the germplasm analyzed. Information generated in this study aids in making informed decisions on the constitution of source populations for doubled haploid (DH) line development in tropical germplasm, particularly those derived from elite maize lines from CIMMYT. The C1-I gene-specific molecular markers identified and validated will facilitate high-throughput and cost-effective evaluation of a large pool of germplasm for the presence of the dominant color inhibitor in maize germplasm.
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Affiliation(s)
- Vijay Chaikam
- International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600, Mexico D.F, Mexico
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16
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Rollins KE, Trim NL, Luddington RJ, Colah S, Klein A, Besser MW, Nair SK. Coagulopathy associated with massive cell salvage transfusion following aortic surgery. Perfusion 2011; 27:30-3. [DOI: 10.1177/0267659111420322] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cell saver blood is used within the peri-operative setting of cardiothoracic surgery to reduce the need for transfusion of allogenic blood products. Several meta-analyses have proven a significant decrease in allogenic transfusion with the use of cell salvage techniques. Washing of red cells by the cell saver and subsequent transfusion of suspended red cells can occasionally cause coagulopathy, particularly when using high concentration heparin saline to wash the spilled blood. We present the case of a 74-year-old female who underwent complicated aortic surgery and was transfused large volumes of cell-saved blood due to post-operative bleeding, which subsequently led to coagulopathy.
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Affiliation(s)
- KE Rollins
- Department of Cardiothoracic Surgery, Papworth Hospital, Papworth Everard, Cambridge, UK
| | - NL Trim
- Department of Haematology, Addenbrookes Hospital, Cambridge, UK
| | - RJ Luddington
- Department of Haematology, Addenbrookes Hospital, Cambridge, UK
| | - S Colah
- Department of Perfusion, Papworth Hospital, Papworth Everard, Cambridge, UK
| | - A Klein
- Department of Anaesthesia, Papworth Hospital, Papworth Everard, Cambridge, UK
| | - MW Besser
- Department of Haematology, Papworth Hospital, Papworth Everard, Cambridge, UK
| | - SK Nair
- Department of Cardiothoracic Surgery, Papworth Hospital, Papworth Everard, Cambridge, UK
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Sameri M, Nakamura S, Nair SK, Takeda K, Komatsuda T. A quantitative trait locus for reduced culm internode length in barley segregates as a Mendelian gene. Theor Appl Genet 2009; 118:643-52. [PMID: 19034412 DOI: 10.1007/s00122-008-0926-9] [Citation(s) in RCA: 5] [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: 04/22/2008] [Accepted: 10/24/2008] [Indexed: 05/04/2023]
Abstract
Yield losses caused by lodging in cereals can be partially controlled by reducing plant height. A progeny of recombinant inbred lines from a cross of two Japanese barley varieties was used to study the inheritance of culm and culm internode lengths. An unexpected QTL for reduced culm length (qCUL), which affected mainly the length of the third and fourth culm internodes, was contributed by 'Kanto Nakate Gold'. This QTL was also associated with reduced lodging in two experiments. A near-isogenic line (culm length 62.9-73.4 cm) in an 'Azumamugi' background, carrying a chromosome segment containing the qCUL allele from Kanto Nakate Gold, was significantly shorter than its recurrent parent (82.9-89.4 cm). The F(2) generation from the next backcross segregated for plant height in a Mendelian monogenic ratio. The qCUL locus was shown to be tightly linked (1.2 cM) with the codominant STS marker ABG608.
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Affiliation(s)
- M Sameri
- National Institute of Agrobiological Sciences (NIAS), Tsukuba, Ibaraki 305-8602, Japan
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18
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Abstract
To estimate the prevalence of blindness and its causes among those aged 50 years and above in rural Karnataka. A total of 1505 people aged 50 years and above from 15 villages were examined. The participants were selected through a house-to-house survey by the cluster sampling method. Visual acuity was tested using a modified Snellen's chart, and eyes were examined to ascertain the cause of blindness. The prevalence of blindness was 6.6% (95% confidence interval: 5.3-7.8%). Bilateral cataract was the principal cause of blindness among 78.7% of the blind and 12.1% were operated for cataract. In conclusion, the study area has a high burden of cataract blindness. Cataract surgical services should be made readily accessible and available to this rural population.
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Affiliation(s)
- T S Chandrashekhar
- Department of Community Medicine, Kasturba Medical College, Manipal, Karnataka, India.
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Chandrashekhar TS, Bhat HV, Pai RP, Nair SK. Coverage, utilization and barriers to cataract surgical services in rural South India: Results from a population-based study. Public Health 2007; 121:130-6. [PMID: 17215012 DOI: 10.1016/j.puhe.2006.07.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Revised: 06/28/2006] [Accepted: 07/14/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVES To determine the cataract surgical coverage, utilization and barriers to cataract surgery in a rural taluk of south India. STUDY DESIGN A cross-sectional, community-based survey. METHODS A house-to-house survey was carried out in 15 villages that were selected by cluster sampling during January to October, 2002. A total of 1505 people aged 50 years and above were tested for visual acuity (VA) and their eyes examined. Cataract surgical coverage was calculated for people and eyes, and for VA levels of <3/60 and <6/60. Information about details of cataract surgery and barriers to cataract surgery were collected using a pre-designed proforma. RESULTS Cataract surgical coverage was 63% (people) and 51% (eyes) for VA<3/60 compared with 49% (people) and 36% (eyes) for VA<6/60. Of 109 operated eyes, 51.2% of operations were carried out in private hospitals and 33.3% in voluntary/charitable hospitals. Inability to afford the operation (22.9%) and fear of the operation (19.2%) were the main barriers to cataract surgery. CONCLUSIONS The reasons for underutilization of government hospitals are to be investigated. Awareness of low-cost cataract intraocular lens (IOL) non-governmental organization (NGO) surgery and free-of-cost NGO services available in the region needs to be raised. Barriers to cataract surgical services should be addressed by community-based health-education programmes to improve the uptake of existing services.
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Affiliation(s)
- T S Chandrashekhar
- Department of Community Medicine, Kasturba Medical College, Manipal, Karnataka, 576119, India.
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20
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Abstract
Recently determined structures of a number of Myc family proteins have provided significant insights into the molecular nature of complex assembly and DNA binding. These structures illuminate the details of specific interactions that govern the assembly of nucleoprotein complexes and, in doing so, raise more questions regarding Myc biology. In this review, we focus on the lessons provided by these structures toward understanding (1) interactions that govern transcriptional repression by Mad via the Sin3 pathway, (2) homodimerization of Max, (3) heterodimerization of Myc-Max and Mad-Max, and (4) DNA recognition by each of the Max-Max, Myc-Max, and Mad-Max dimers.
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Affiliation(s)
- S K Nair
- Department of Biochemistry and Center for Biophysics & Computational Biology, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, IL 61801, USA.
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21
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Babu R, Nair SK, Kumar A, Rao HS, Verma P, Gahalain A, Singh IS, Gupta HS. Mapping QTLs for popping ability in a popcorn x flint corn cross. Theor Appl Genet 2006; 112:1392-9. [PMID: 16525839 DOI: 10.1007/s00122-006-0242-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Accepted: 02/13/2006] [Indexed: 05/07/2023]
Abstract
Popping expansion volume (PEV) in popcorn (Zea mays L.) is a distinct heritable character and defined as the ratio of the volume after popping to the volume before popping. PEV is quantitatively inherited and 3-4 genes/quantitative trait loci (QTLs) have been implicated. In the present study, we have dissected the quantitative PEV into two component traits, viz., flake volume (FV) and percent unpopped kernels (UPK), and mapped QTLs using SSR markers for all three traits with 194 F3 families derived from a popcorn (A-1-6) x flint corn (V273) cross. Heritability (broad sense) estimates for PEV, FV and UPK based on F3 mean bases were 0.72, 0.54 and 0.68, respectively. The QTL analyses for the three traits based on combined environment data were performed by composite interval mapping using QTL cartographer. Four QTLs were identified for PEV on chromosomes 1, 3, 8 and 10, which together explained 62% of the phenotypic variance (sigma2p). Four QTLs were found on chromosomes 1, 5, 9 and 10 for FV (explaining 44% of sigma2p) and five QTLs for UPK on chromosomes 1, 3, 4, 5 and 9 (explaining 57% of sigma2p). The relative efficiency estimates of marker-based selection in comparison to phenotypic selection for PEV (1.10), FV (1.22) and UPK (1.11) indicated that marker-based selection could be relatively more efficient. The QTL on chromosome 1S for PEV was found to be most significant, where QTLs for hard endosperm starch concentration had been detected earlier.
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Affiliation(s)
- R Babu
- Vivekananda Institute of Hill Agriculture (ICAR), 263601, Almora, Uttaranchal, India.
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22
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Nair SK, Thomas TJ, Greenfield NJ, Chen A, He H, Thomas T. Conformational dynamics of estrogen receptors alpha and beta as revealed by intrinsic tryptophan fluorescence and circular dichroism. J Mol Endocrinol 2005; 35:211-23. [PMID: 16216903 DOI: 10.1677/jme.1.01830] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Estrogen receptors (ER alpha and ER beta) are ligand-activated nuclear receptors that mediate the action of estrogens. These receptors activate transcription by similar mechanism(s), although the overall amino acid sequence identity is only 47%. In order to compare the structural and conformational features of ER alpha and ER beta, we monitored their intrinsic tryptophan fluorescence during thermal unfolding. The 50% unfolding temperatures (T(M)) of ER alpha and ER beta were 39+/-1 and 40+/-2 degrees C, respectively. Estradiol had no significant effect on the T(M) of ER alpha or ER beta. In contrast, binding of the estrogen-response element increased the T(M) of ER alpha and ER beta by 10 degrees C. Thermal unfolding of estradiol-bound ER alpha and ligand-free ER beta showed two-step transitions, with the formation of intermediates that were stable between 36-48 and 34-42 degrees C, respectively. We confirmed the presence of intermediate states during thermal unfolding by circular dichroism spectroscopy. Atomic force microscopy showed that the ER beta intermediate consisted of discrete globular particles, whereas the ER alpha intermediate showed a speckled appearance, with sparse well-defined particles. Fluorescence-quenching studies showed the presence of two classes of tryptophan in unliganded ER alpha and ER beta. Binding of estradiol to ER beta exposed its tryptophans, whereas estradiol reduced the accessibility of the tryptophans of ER alpha. Our results illustrate the differential effects of ligands on the unfolding of ER alpha and ER beta, and identify partially unfolded intermediates. Differences in the conformational flexibility and stability of ER alpha and ER beta may represent functional differences of ligand-bound ERs in recruiting coactivator proteins and initiating transcription.
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Affiliation(s)
- S K Nair
- Department of Environmental & Occupational Medicine, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, New Brunswick, NJ 08903, USA
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23
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Babu R, Nair SK, Kumar A, Venkatesh S, Sekhar JC, Singh NN, Srinivasan G, Gupta HS. Two-generation marker-aided backcrossing for rapid conversion of normal maize lines to quality protein maize (QPM). Theor Appl Genet 2005; 111:888-97. [PMID: 16034586 DOI: 10.1007/s00122-005-0011-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Accepted: 05/31/2005] [Indexed: 05/03/2023]
Abstract
The low nutritive value of maize endosperm protein is genetically corrected in quality protein maize (QPM), which contains the opaque 2 gene along with numerous modifiers for kernel hardness. We report here a two generation marker-based backcross breeding program for incorporation of the opaque 2 gene along with phenotypic selection for kernel modification in the background of an early maturing normal maize inbred line, V25. Using the flanking marker distances from opaque 2 gene in the cross V 25 xCML 176, optimum population size for the BC(2) generation was computed in such a way that at least one double recombinant could be obtained. Whole genome background selection in the BC(2) generation identified three plants with 93 to 96% recurrent parent genome content. The three BC(2)F(2) families derived from marker identified BC(2) individuals were subjected to foreground selection and phenotypic selection for kernel modification. The tryptophan concentration in endosperm protein was significantly enhanced in all the three classes of kernel modification viz., less than 25%, 25--50% and more than 50% opaqueness. BC(2)F(3) lines developed from the hard endosperm kernels were evaluated for desirable agronomic and biochemical traits in replicated trials and the best line was chosen to represent the QPM version of V25, with tryptophan concentration of 0.85% in protein. The integrated breeding strategy reported here can be applied to reduce genetic drag as well as the time involved in a conventional line conversion program, and would prove valuable in rapid development of specialty corn germ plasm.
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Affiliation(s)
- R Babu
- Vivekananda Institute of Hill Agriculture (ICAR), Almora, Uttaranchal 263601, India.
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24
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Nair SK, Prasanna BM, Garg A, Rathore RS, Setty TAS, Singh NN. Identification and validation of QTLs conferring resistance to sorghum downy mildew (Peronosclerospora sorghi) and Rajasthan downy mildew (P. heteropogoni) in maize. Theor Appl Genet 2005; 110:1384-92. [PMID: 15841363 DOI: 10.1007/s00122-005-1936-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2004] [Accepted: 01/11/2005] [Indexed: 05/20/2023]
Abstract
We have mapped the quantitative trait loci (QTLs) conferring resistance to sorghum downy mildew (Peronosclerospora sorghi; SDM) and Rajasthan downy mildew (P. heteropogoni; RDM), two species of DM prevalent throughout India. QTL mapping was carried out on a backcross population of 151 individuals derived from a cross between CM139 (susceptible parent) and NAI116 (highly resistant to both SDM and RDM). Heritability estimates were 0.74 for SDM and 0.67 for RDM. Composite interval mapping combined with a linkage map constructed with 80 simple sequence repeat (SSR) markers resulted in the identification of three QTLs (one each on chromosomes 2, 3 and 6) for SDM resistance and two QTLs (one each on chromosomes 3 and 6) for RDM resistance, all of which were contributed by NAI116. The significance of the major QTL on chromosome 6 (bin 6.05) that confers resistance to diverse DMs in tropical Asia, including SDM and RDM in India, was also verified. The results confirmed that some common QTLs contribute to both SDM and RDM resistance, while additional loci might specifically govern resistance to SDM. The QTL information generated in this study provide information that will aid in undertaking an integrated breeding strategy for the transfer of resistance to SDM and RDM in maize lines using marker-assisted selection.
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Affiliation(s)
- S K Nair
- Maize Genetics Unit, Indian Agricultural Research Institute, New Delhi, 110012, India
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25
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Rafeeq AK, Rajagopal S, Sureshkumar J, Bafana M, Nair SG, Nair SK. Coronary artery bypass grafting in female patients on thyroxin replacement therapy. Indian J Thorac Cardiovasc Surg 2004. [DOI: 10.1007/s12055-004-0332-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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26
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Sarma AK, Sai Kiran KVSS, Rajnish D, Jayakumar K, Nair SK, Unnikrishnan M, Neelakandhan KS. Combined coronary artery bypass grafting and abdominal aortic aneurysm repair. Indian J Thorac Cardiovasc Surg 2004. [DOI: 10.1007/s12055-004-0327-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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27
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Abstract
[see structure]. An efficient, concise approach to the macrolide core of the cryptophycins, potent antimitotic agents, has been achieved. The reaction sequence features a novel macrolactonization utilizing a reactive acyl-beta-lactam intermediate that incorporates the beta-amino acid moiety within the 16-membered macrolide core. This highly modular approach, which allows for multiple alterations throughout the structure, was successfully applied to the total synthesis of cryptophycin-24.
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Affiliation(s)
- M Eggen
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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28
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Heiser A, Maurice MA, Yancey DR, Wu NZ, Dahm P, Pruitt SK, Boczkowski D, Nair SK, Ballo MS, Gilboa E, Vieweg J. Induction of polyclonal prostate cancer-specific CTL using dendritic cells transfected with amplified tumor RNA. J Immunol 2001; 166:2953-60. [PMID: 11207244 DOI: 10.4049/jimmunol.166.5.2953] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Polyvalent cancer vaccines targeting the entire antigenic spectrum on tumor cells may represent a superior therapeutic strategy for cancer patients than vaccines solely directed against single Ags. In this study, we show that autologous dendritic cells (DC) transfected with RNA amplified from microdissected tumor cells are capable of stimulating CTL against a broad set of unidentified and critical prostate-specific Ags. Although the polyclonal CTL responses generated with amplified tumor RNA-transfected DC encompassed as a subcomponent a response against prostate-specific Ag (PSA) as well as against telomerase reverse transcriptase, the tumor-specific CTL were consistently more effective than PSA or telomerase reverse transcriptase CTL to lyse tumor targets, suggesting the superiority of the polyclonal response. Although tumor RNA-transfected DC stimulated CTL, which recognized not only tumor but also self-Ags expressed by benign prostate tissue, these cross-reactive CTL were exclusively specific for the PSA, indicating an immunodominant role of PSA in the prostate cancer-specific immune response. Our data suggest that tumor RNA-transfected DC may represent a broadly applicable, potentially clinically effective vaccine strategy for prostate cancer patients, which is not limited by tumor tissue availability for Ag preparation and may minimize the risk of clonal tumor escape.
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MESH Headings
- Adjuvants, Immunologic/genetics
- Adjuvants, Immunologic/metabolism
- Cells, Cultured
- Clone Cells
- Cross Reactions/genetics
- Cytotoxicity Tests, Immunologic
- Cytotoxicity, Immunologic/genetics
- Dendritic Cells/immunology
- Dendritic Cells/metabolism
- Dissection
- Epitopes, T-Lymphocyte/immunology
- Gene Amplification/immunology
- Humans
- Lymphocyte Activation/genetics
- Male
- Prostate-Specific Antigen/immunology
- Prostate-Specific Antigen/metabolism
- Prostatic Neoplasms/genetics
- Prostatic Neoplasms/immunology
- Prostatic Neoplasms/metabolism
- RNA, Messenger/immunology
- RNA, Messenger/metabolism
- RNA, Neoplasm/genetics
- RNA, Neoplasm/immunology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- Transcription, Genetic/immunology
- Transfection
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Affiliation(s)
- A Heiser
- Department of Surgery, Division of Urology, Duke University Medical Center, Durham, NC 27710, USA
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29
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Neema PK, Nair SK. Critical stenosis of bicarotid trunk and left subclavian artery with severe coronary artery disease - a management dilemma. Ann Card Anaesth 2001; 4:33-6. [PMID: 17851160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Abstract
A 48 yr. old patient suffering from bicarotid trunk and left subclavian artery stenosis with severe coronary artery disease was managed successfully by angioplasty and stenting of the bicarotid trunk and subclavian artery. This was followed by coronary artery bypass grafting after one month. He was free of angina and cerebrovascular symptoms at one and a half year follow up.
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Affiliation(s)
- P K Neema
- Department of Anaesthesia and Cardiovascular Surgery, Sree Chitra Tirunal Institute for Medical Sciences and Techonology, Trivandrum, India
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30
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Eggen M, Mossman CJ, Buck SB, Nair SK, Bhat L, Ali SM, Reiff EA, Boge TC, Georg GI. Total synthesis of cryptophycin-24 (Arenastatin A) amenable to structural modifications in the C16 side chain. J Org Chem 2000; 65:7792-9. [PMID: 11073583 DOI: 10.1021/jo000767+] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two efficient protocols for the synthesis of tert-butyl (5S,6R,2E, 7E)-5-[(tert-butyldimethylsilyl)oxy]-6-methyl-8-phenyl-2, 7-octadienoate, a major component of the cryptophycins, are reported. The first utilized the Noyori reduction and Frater alkylation of methyl 5-benzyloxy-3-oxopentanoate to set two stereogenic centers, which became the C16 hydroxyl and C1' methyl of the cryptophycins. The second approach started from 3-p-methoxybenzyloxypropanal and a crotyl borane reagent derived from (-)-alpha-pinene to set both stereocenters in a single step and provided the dephenyl analogue, tert-butyl (5S,6R,2E)-5-[(tert-butyldimethylsilyl)oxy]-6-methyl-2, 7-octadienoate, in five steps. This compound was readily converted to the 8-phenyl compound via Heck coupling. The silanyloxy esters were efficiently deprotected and coupled to the C2-C10 amino acid fragment to provide desepoxyarenastatin A and its dephenyl analogue. The terminal olefin of the latter was further elaborated via Heck coupling. Epoxidation provided cryptophycin-24 (arenastatin A).
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Affiliation(s)
- M Eggen
- Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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31
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Mosca PJ, Hobeika AC, Clay TM, Nair SK, Thomas EK, Morse MA, Lyerly HK. A subset of human monocyte-derived dendritic cells expresses high levels of interleukin-12 in response to combined CD40 ligand and interferon-gamma treatment. Blood 2000; 96:3499-504. [PMID: 11071647] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Dendritic cells (DCs) may arise from multiple lineages and progress through a series of intermediate stages until fully mature, at which time they are capable of optimal antigen presentation and T-cell activation. High cell surface expression of CD83 is presumed to correlate with full maturation of DCs, and a number of agents have been shown to increase CD83 expression on DCs. We hypothesized that interleukin 12 (IL-12) expression would be a more accurate marker of functionally mature DCs capable of activating antigen-specific T cells. We used combinations of signaling through CD40, using CD40 ligand trimer (CD40L), and interferon gamma to demonstrate that CD83 expression is necessary but not sufficient for optimal production of IL-12 by DCs. Phenotypically mature DCs could be induced to produce high levels of IL-12 p70 only when provided 2 simultaneous stimulatory signals. By intracellular cytokine detection, we determined that only a subset of cells that express high levels of CD80 and CD83 generate large amounts of IL-12. DCs matured with both signals are superior to DCs stimulated with the individual agents in activating antigen-specific T cell in vitro. These findings have important implications regarding the identification, characterization, and clinical application of functionally mature DCs.
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Affiliation(s)
- P J Mosca
- Departments of General and Thoracic Surgery, Pathology, Immunology, and Internal Medicine, Center for Genetic and Cellular Therapies, Duke University Medical Center, Durham, NC, USA
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Affiliation(s)
- D A Mitchell
- Center for Cellular and Genetic Therapies, Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
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33
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Nair SK, Heiser A, Boczkowski D, Majumdar A, Naoe M, Lebkowski JS, Vieweg J, Gilboa E. Induction of cytotoxic T cell responses and tumor immunity against unrelated tumors using telomerase reverse transcriptase RNA transfected dendritic cells. Nat Med 2000; 6:1011-7. [PMID: 10973321 DOI: 10.1038/79519] [Citation(s) in RCA: 265] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The polypeptide component of telomerase (TERT) is an attractive candidate for a broadly expressed tumor rejection antigen because telomerase is silent in normal tissues but is reactivated in more than 85% of cancers. Here we show that immunization against TERT induces immunity against tumors of unrelated origin. Immunization of mice with TERT RNA-transfected dendritic cells (DC) stimulated cytotoxic T lymphocytes (CTL), which lysed melanoma and thymoma tumor cells and inhibited the growth of three unrelated tumors in mice of distinct genetic backgrounds. TERT RNA-transfected human DC stimulated TERT-specific CTL in vitro that lysed human tumor cells, including Epstein Barr virus (EBV)-transformed B cells as well as autologous tumor targets from patients with renal and prostate cancer. Tumor RNA-transfected DC were used as surrogate targets in the CTL assays, obviating the difficulties in obtaining tumor cells from cancer patients. In one instance, where a tumor cell line was successfully established in culture from a patient with renal cancer, the patient's tumor cells were efficiently lysed by the CTL. Immunization with tumor RNA was generally more effective than immunization with TERT RNA, suggesting that an optimal immunization protocol may have to include TERT as well as additional tumor antigens.
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MESH Headings
- Animals
- Antigens, Neoplasm/genetics
- Antigens, Neoplasm/immunology
- Antigens, Neoplasm/therapeutic use
- B-Lymphocytes
- Cancer Vaccines/therapeutic use
- Cell Transformation, Viral
- Dendritic Cells/immunology
- H-2 Antigens
- Herpesvirus 4, Human
- Humans
- Immunotherapy
- Kidney Neoplasms/immunology
- Male
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Neoplasms, Experimental/prevention & control
- Prostatic Neoplasms/immunology
- RNA/genetics
- RNA/immunology
- RNA/therapeutic use
- T-Lymphocytes, Cytotoxic
- Telomerase/genetics
- Telomerase/immunology
- Telomerase/therapeutic use
- Vaccines, Synthetic/therapeutic use
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Affiliation(s)
- S K Nair
- Department of Surgery, Center for Genetic and Cellular Therapies, Duke University Medical Center, Durham, NC 27710, USA
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Kodaira Y, Nair SK, Wrenshall LE, Gilboa E, Platt JL. Phenotypic and functional maturation of dendritic cells mediated by heparan sulfate. J Immunol 2000; 165:1599-604. [PMID: 10903769 DOI: 10.4049/jimmunol.165.3.1599] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Primary immune responses are thought to be induced by dendritic cells. To promote such responses, dendritic cells must be activated by exogenous agonists, such as LPS, or by products of activated leukocytes, such as TNF-alpha and IL-1. How dendritic cells might be activated in the absence of exogenous stimuli, or without the immediate presence of activated leukocytes, as might occur in immunity to tumor cells or transplants, is unknown. We postulated that heparan sulfate, an acidic, biologically active polysaccharide associated with cell membranes and extracellular matrices, which is rapidly released under conditions of inflammation and tissue damage, might provide such a stimulus. Incubation of immature murine dendritic cells with heparan sulfate induced phenotypic maturation evidenced by up-regulation of I-A, CD40, CD54 (ICAM-1), CD80 (B7-1), and CD86 (B7-2). Dendritic cells exposed to heparan sulfate exhibited a markedly lowered rate of Ag uptake and increased allostimulatory capacity. Stimulation of dendritic cells with heparan sulfate induced release of TNF-alpha, IL-1beta, and IL-6, although the maturation of dendritic cells was independent of these cytokines. These results suggest that soluble heparan sulfate chains, as products of the degradation of heparan sulfate proteoglycan, might induce maturation of dendritic cells without exogenous stimuli, thus contributing to the generation and maintenance of primary immune responses.
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Affiliation(s)
- Y Kodaira
- Department of Surgery, Mayo Clinic, Rochester, MN 55905, USA
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35
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Kumaraguru U, Rouse RJ, Nair SK, Bruce BD, Rouse BT. Involvement of an ATP-dependent peptide chaperone in cross-presentation after DNA immunization. J Immunol 2000; 165:750-9. [PMID: 10878348 DOI: 10.4049/jimmunol.165.2.750] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Immunization with plasmid DNA holds promise as a vaccination strategy perhaps useful in situations that currently lack vaccines, since the major means of immune induction may differ from more conventional approach. In the present study, we demonstrate that exposure of macrophages to plasmid DNA encoding viral proteins or OVA generates Ag-specific material that, when presented in vitro by dendritic cells to naive T cells, induces primary CTL response or elicits IL-2 production from an OVA peptide-specific T-T hybridoma. The immunogenic material released was proteinaceous in nature, free of apoptotic bodies, and had an apparent m.w. much larger than a 9-11-aa CTL-recognizable peptide. The macrophage-released factor(s) specifically required a hydrolyzable ATP substrate and was inhibited by procedures that removed or hydrolyzed ATP; in addition, anti-heat-shock protein 70 antiserum abrogated the activity to a large extent. These results indicate the possible involvement of a heat-shock protein 70-linked peptide chaperone in a cross-priming method of immune induction by DNA vaccination. Such a cross-priming process may represent a principal mechanism by which plasmid DNA delivered to cells such as myocytes effectively shuttle Ag to DC or other APC to achieve CTL induction in vivo.
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Affiliation(s)
- U Kumaraguru
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA
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36
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Larchian WA, Horiguchi Y, Nair SK, Fair WR, Heston WD, Gilboa E. Effectiveness of combined interleukin 2 and B7.1 vaccination strategy is dependent on the sequence and order: a liposome-mediated gene therapy treatment for bladder cancer. Clin Cancer Res 2000; 6:2913-20. [PMID: 10914741] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We have developed a novel liposome-mediated immunogene therapy using interleukin 2 (IL-2) and B7.1 in a murine bladder cancer model. A carcinogen-induced murine bladder cancer cell line, MBT-2, was transfected with cationic liposome 1,2-dimyristyloxypropyl-3-dimethyl-hydroxyethyl ammonium bromide/dioleolylphosphatidylethanolamine and IL-2 plasmid. The optimized transfection condition generated IL-2 levels of 245-305 ng/10(6) cells/24 h, 100-fold higher than the levels seen with retrovirus transfection. Ninety percent of the peak level of IL-2 production was maintained for up to 11 days after transfection. Animal studies were conducted in C3H/HeJ female mice with 2 x 10(4) MBT-2 cells implanted orthotopically on day 0. Multiple vaccination schedules were performed with i.p. injection of 5 x 10(6) IL-2 and/or B7.1 gene-modified cell preparations. The greatest impact on survival was observed with the day 5, 10, and 15 regimen. Control animals receiving retrovirally gene-modified MBT-2/IL-2 cell preparations had a median survival of 29 days. Animals receiving the IL-2 liposomally gene-modified cell preparation alone had a median survival of 46 days. Seventy-five percent of animals receiving IL-2 followed by B7.1 gene-modified tumor vaccines were the only group to show complete tumor-free survival at day 60. All of these surviving animals rejected the parental MBT-2 tumor rechallenge and survived at day 120 with a high CTL response. In conclusion, liposome-mediated transfection demonstrates a clear advantage as compared with the retroviral system in the MBT-2 model. Multi-agent as opposed to single-agent cytokine gene-modified tumor vaccines were beneficial. These "targeted" sequential vaccinations using IL-2 followed by B7.1 gene-modified tumor cells significantly increased a systemic immune response that translated into increased survival.
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Affiliation(s)
- W A Larchian
- Department of Urology, The Cleveland Clinic Foundation, Ohio 44195, USA.
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Thornburg C, Boczkowski D, Gilboa E, Nair SK. Induction of cytotoxic T lymphocytes with dendritic cells transfected with human papillomavirus E6 and E7 RNA: implications for cervical cancer immunotherapy. J Immunother 2000; 23:412-8. [PMID: 10916750 DOI: 10.1097/00002371-200007000-00004] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human papillomavirus (HPV) infection is associated with cervical cancer. The high-risk HPV E6 and E7 oncoproteins are constitutively expressed in most cervical carcinoma cells, and are, therefore, attractive antigens for cytotoxic T-lymphocyte (CTL)-mediated immunotherapy. The objective of this study was to evaluate the use of dendritic cells (DCs) transfected with RNA encoding the E6 and E7 protein for cervical cancer immunotherapy. The authors have shown that DCs transfected with RNA-encoding antigen stimulate potent antigen-specific CTL responses in vitro and in vivo. In this study, they tried to determine whether DCs transfected with E6 and E7 RNA stimulate primary, antigen-specific CTL responses in vitro. The results show that DCs pulsed with E6 or E7 RNA stimulate antigen-specific CTL responses that recognize and lyse DCs transfected with E6 and E7 RNA and human cervical carcinoma cells expressing the E6 and E7 products, and the lysis was comparable to that achieved with E6 and E7 peptide-pulsed DCs. Dendritic cells cotransfected with both E6 and E7 RNA stimulate CTLs that are more effective at lysing human cervical cancer cells. This study provides a rationale for the development of cervical carcinoma immunotherapy using DCs transfected with HPV E6 and E7 RNA.
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Affiliation(s)
- C Thornburg
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
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Apostoaei AI, Nair SK, Thomas BA, Lewis CJ, Hoffman FO, Thiessen KM. External exposure to radionuclides accumulated in shoreline sediments with an application to the lower Clinch River. Health Phys 2000; 78:700-710. [PMID: 10832931 DOI: 10.1097/00004032-200006000-00014] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A simple analytical method was developed to estimate external doses from exposure to contaminated riverine shorelines. The method consists of deriving an adjustment factor that accounts for the geometry of the riverine shoreline; the adjustment factor is applied to the dose-rate coefficients already available for infinite contaminated surfaces. Such a geometry factor circumvents very complex radiation transport calculations which would otherwise be necessary to model exposures to a finite contaminated surface. For instance, for radionuclides emitting gamma rays of energies above 600 keV (e.g., 137Cs), the published dose-rate coefficients must be reduced by 75%, 60%, 50%, and 33% for shoreline widths of 4, 10, 20, and 50 m, respectively. The geometry factor changes only mildly with the energy of the gamma radiation. This property allows for the geometry factor to be used for radionuclides emitting multiple gamma rays of various energies. If a quick analysis is desired, the geometry factors derived for 137Cs can be used for all radionuclides. More refined analysis can be performed by deriving geometry factors for each radionuclide according to its gamma spectrum. Also, the mild variation with energy allows the geometry factors to be applied to the case when radionuclides are accumulated in layers under the soil surface, and not only to the case when radionuclides are deposited onto the soil surface. Empirical relationships between the geometry factor and the dimension of the shoreline were provided so that one can obtain values of the geometry factor for any shoreline width. These relationships can be easily used to account for the uncertainty in the dimension of the shoreline. The method was applied to derive similar adjustment factors for contaminated surfaces of other simple geometries (e.g., circular surfaces). An example of how this method can be applied to its full extent is presented for the case of external exposure to the shores of the lower Clinch River. This river received large amounts of 137Cs, 60Co, 106Ru, 95Zr, 95Nb, 144Ce, and 90Sr released during 1944-1991 from the Oak Ridge Reservation in Oak Ridge, Tennessee.
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Heiser A, Dahm P, Yancey DR, Maurice MA, Boczkowski D, Nair SK, Gilboa E, Vieweg J. Human dendritic cells transfected with RNA encoding prostate-specific antigen stimulate prostate-specific CTL responses in vitro. J Immunol 2000; 164:5508-14. [PMID: 10799919 DOI: 10.4049/jimmunol.164.10.5508] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although immunological tolerance to self Ags represents an important mechanism to prevent normal tissue injury, there is growing evidence that tolerance to tumor Ags, which often represent normal peripherally expressed proteins, is not absolute and can be effectively reverted. Prostate-specific Ag (PSA) is a self Ag expressed by both normal and malignant prostatic epithelium, and therefore offers a unique opportunity to examine the ability of self Ags to serve as specific CTL targets. In this study, we investigated the efficacy of autologous dendritic cells (DC) transfected with mRNA encoding PSA to stimulate CTL against PSA Ags in vitro. Ag in form of RNA carries the advantage to encode multiple epitopes for many HLA alleles, thus permitting induction of CTL responses among many cancer patients independent of their HLA repertoire. In this study, we show that PSA mRNA-transfected DC were capable of stimulating primary CTL responses against PSA Ags in vitro. The PSA-specific CTL did not cross-react with kallikrein Ags, a protein, which shares significant homology with PSA, suggesting that harmful autoimmune toxicity may not represent a significant problem with this approach. PSA RNA-transfected DC generated from male or female healthy volunteers or from cancer patients were equally effective in stimulating PSA-specific CTL in vitro, implying that neither natural tolerance to PSA Ags nor tumor-mediated T cell anergy may represent major barriers for CTL generation against the self Ag PSA. This study provides a preclinical rationale for using PSA RNA-transfected DC in active or adoptive immunization protocols.
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Affiliation(s)
- A Heiser
- Division of Urology and Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
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Nair SK, Apostoaei AI, Hoffman FO. A radioiodine speciation, deposition, and dispersion model with uncertainty propagation for the Oak Ridge dose reconstruction. Health Phys 2000; 78:394-413. [PMID: 10749523 DOI: 10.1097/00004032-200004000-00004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Between 1944 and 1956, radioactive 131I was released into the atmosphere from operations at the Oak Ridge National Laboratory in Oak Ridge, TN. The releases occurred from stacks and from building vents and openings in three different chemical forms: elemental, organic, and particulate. During their transport in the atmosphere, different forms of iodine react differently with other atmospheric chemicals and moisture, and are removed from the plume at different rates by the processes of dry and wet deposition. A modified Gaussian plume model was developed to address the processes of radioiodine speciation, deposition, depletion, and dispersion in the atmosphere, and to propagate uncertainties in input parameter values through to the ground-level concentrations of 131I in air. A unique approach was used to develop an implicitly correlated set of hourly meteorological parameters for any day of a month for each month of the year from ten years of available data between 1987 and 1996. The model was validated for both annual average and short-term releases. For the annual average releases, the predictions of ground-level concentrations of 131I from the model were within a factor of 2 of measured field data. For two of the three sets of available weekly data, the measurements fell within the 95% subjective confidence interval of model predictions. Predictions of ground-level air concentrations were made on an annual average basis for the entire period of release and on a short-term, episodic basis for a 1954 accident.
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Affiliation(s)
- S K Nair
- The Cadmus Group, Inc., Oak Ridge, TN 37830, USA.
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Mitchell DA, Nair SK. RNA transfected dendritic cells as cancer vaccines. Curr Opin Mol Ther 2000; 2:176-81. [PMID: 11249639] [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: 02/19/2023]
Abstract
Immunization with dendritic cells loaded with tumor antigens could represent a powerful method of inducing antitumor immunity. Studies from several laboratories have shown that immunization with dendritic cells pulsed with specific antigens prime cytotoxic T-cells and engender tumor immunity. This review will focus on the use of dendritic cells transfected with RNA as cancer vaccines, with emphasis on the potential advantages of using RNA. The majority of cancer patients who lack an identified tumor antigen and/or cannot provide sufficient tumor tissue for antigen preparation will be excluded from treatment with cancer vaccines based on using either specific tumor antigens or mixtures of tumor-derived antigens in the form of peptides or proteins isolated from tumor cells. Vaccination with the mRNA content of tumor cells would extend the scope of vaccination to this group of patients as well because RNA can be amplified from very few cancer cells.
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Affiliation(s)
- D A Mitchell
- Center for Cellular and Genetic Therapies, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
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Boczkowski D, Nair SK, Nam JH, Lyerly HK, Gilboa E. Induction of tumor immunity and cytotoxic T lymphocyte responses using dendritic cells transfected with messenger RNA amplified from tumor cells. Cancer Res 2000; 60:1028-34. [PMID: 10706120] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Unique patient-specific tumor antigens may constitute the dominant antigens in the antitumor immune response. Hence, vaccination with the patient's own repertoire of tumor antigens may offer a superior strategy to elicit protective immunity. We have shown previously that dendritic cells transfected with mRNA isolated from tumor cells stimulate potent CTL responses and engender protective immunity in tumor-bearing mice. In the current study, we demonstrate that tumor mRNA, isolated from murine tumor cell lines or from primary human tumor cells microdissected from frozen tissue sections, can be amplified without loss of function. This study provides the foundations for an effective and broadly applicable treatment that does not require the characterization of the relevant antigenic profile in each patient and will not be limited by tumor tissue availability for antigen preparation.
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Affiliation(s)
- D Boczkowski
- Center for Genetic and Cellular Therapies, Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
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Nair SK, Hull S, Coleman D, Gilboa E, Lyerly HK, Morse MA. Induction of carcinoembryonic antigen (CEA)-specific cytotoxic T-lymphocyte responses in vitro using autologous dendritic cells loaded with CEA peptide or CEA RNA in patients with metastatic malignancies expressing CEA. Int J Cancer 1999; 82:121-4. [PMID: 10360830 DOI: 10.1002/(sici)1097-0215(19990702)82:1<121::aid-ijc20>3.0.co;2-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The application of dendritic cells (DC) to the active immunotherapy of cancer currently relies on the generation of potent DC capable of presenting tumor antigens such as carcinoembryonic antigen (CEA). It is unknown whether the T cells of patients with advanced malignancies can be reliably stimulated against tumor antigens by their autologous DC. In this study, starting with the peripheral blood mononuclear cells (PBMC) of patients with metastatic malignancies expressing CEA, autologous DCs were generated in vitro in serum-free media supplemented with GM-CSF and IL-4. The DCs from HLA A2 positive patients were loaded with the CEA peptide CAP-1 and the DCs from HLA A2 negative patients were depleted of bystander lymphocytes and loaded with mRNA encoding CEA. The DC preparations were tested to determine their phenotype and were used to stimulate autologous PBMC twice, separated by 10-14 days. The stimulated cells were then tested for their ability to lyse CEA-expressing target cells. We successfully generated an adequate number of DC for a clinical trial from all patients. The harvested DC preparations contained 49% DC and 87% DC if depleted of bystander lymphocytes. Phenotypic analysis showed the typical pattern of CD11c+ CD40+ CD86+ HLA-DR+ CD80(low) CD83(low) CD14(low). All preparations but one were able to stimulate CEA-specific cytotoxic T-lymphocyte (CTL) activity, suggesting that the majority of patients are not anergic to CEA and possess functional DC. The CTL activity was similar for the CEA peptide and CEA RNA-loaded DC.
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Affiliation(s)
- S K Nair
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
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Nair SK, Hull S, Coleman D, Gilboa E, Lyerly HK, Morse MA. Induction of carcinoembryonic antigen (CEA)-specific cytotoxic T-lymphocyte responses in vitro using autologous dendritic cells loaded with CEA peptide or CEA RNA in patients with metastatic malignancies expressing CEA. Int J Cancer 1999. [PMID: 10360830 DOI: 10.1002/(sici)1097-0215(19990702)82] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The application of dendritic cells (DC) to the active immunotherapy of cancer currently relies on the generation of potent DC capable of presenting tumor antigens such as carcinoembryonic antigen (CEA). It is unknown whether the T cells of patients with advanced malignancies can be reliably stimulated against tumor antigens by their autologous DC. In this study, starting with the peripheral blood mononuclear cells (PBMC) of patients with metastatic malignancies expressing CEA, autologous DCs were generated in vitro in serum-free media supplemented with GM-CSF and IL-4. The DCs from HLA A2 positive patients were loaded with the CEA peptide CAP-1 and the DCs from HLA A2 negative patients were depleted of bystander lymphocytes and loaded with mRNA encoding CEA. The DC preparations were tested to determine their phenotype and were used to stimulate autologous PBMC twice, separated by 10-14 days. The stimulated cells were then tested for their ability to lyse CEA-expressing target cells. We successfully generated an adequate number of DC for a clinical trial from all patients. The harvested DC preparations contained 49% DC and 87% DC if depleted of bystander lymphocytes. Phenotypic analysis showed the typical pattern of CD11c+ CD40+ CD86+ HLA-DR+ CD80(low) CD83(low) CD14(low). All preparations but one were able to stimulate CEA-specific cytotoxic T-lymphocyte (CTL) activity, suggesting that the majority of patients are not anergic to CEA and possess functional DC. The CTL activity was similar for the CEA peptide and CEA RNA-loaded DC.
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Affiliation(s)
- S K Nair
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
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Nair SK, Hull S, Coleman D, Gilboa E, Lyerly HK, Morse MA. Induction of carcinoembryonic antigen (CEA)-specific cytotoxic T-lymphocyte responses in vitro using autologous dendritic cells loaded with CEA peptide or CEA RNA in patients with metastatic malignancies expressing CEA. Int J Cancer 1999. [PMID: 10360830 DOI: 10.1002/(sici)1097-0215(19990702)82:1<121::aid-ijc20>3.0.co;2-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The application of dendritic cells (DC) to the active immunotherapy of cancer currently relies on the generation of potent DC capable of presenting tumor antigens such as carcinoembryonic antigen (CEA). It is unknown whether the T cells of patients with advanced malignancies can be reliably stimulated against tumor antigens by their autologous DC. In this study, starting with the peripheral blood mononuclear cells (PBMC) of patients with metastatic malignancies expressing CEA, autologous DCs were generated in vitro in serum-free media supplemented with GM-CSF and IL-4. The DCs from HLA A2 positive patients were loaded with the CEA peptide CAP-1 and the DCs from HLA A2 negative patients were depleted of bystander lymphocytes and loaded with mRNA encoding CEA. The DC preparations were tested to determine their phenotype and were used to stimulate autologous PBMC twice, separated by 10-14 days. The stimulated cells were then tested for their ability to lyse CEA-expressing target cells. We successfully generated an adequate number of DC for a clinical trial from all patients. The harvested DC preparations contained 49% DC and 87% DC if depleted of bystander lymphocytes. Phenotypic analysis showed the typical pattern of CD11c+ CD40+ CD86+ HLA-DR+ CD80(low) CD83(low) CD14(low). All preparations but one were able to stimulate CEA-specific cytotoxic T-lymphocyte (CTL) activity, suggesting that the majority of patients are not anergic to CEA and possess functional DC. The CTL activity was similar for the CEA peptide and CEA RNA-loaded DC.
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Affiliation(s)
- S K Nair
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
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Morse MA, Lyerly HK, Gilboa E, Thomas E, Nair SK. Optimization of the sequence of antigen loading and CD40-ligand-induced maturation of dendritic cells. Cancer Res 1998; 58:2965-8. [PMID: 9679955] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Dendritic cells (DCs), matured by CD40-ligand (CD40L), undergo marked changes in their ability to process and present antigen, resulting in augmented lymphocyte stimulatory activity. We demonstrate that the form of the tumor antigen (peptide or genetic material) used to load the DCs dictates the required sequence of antigen loading and maturation for antitumor immunotherapy. Optimal stimulation of carcinoembryonic antigen (CEA)-specific CTLs by peptide-loaded DCs occurs when DCs from cancer patients are matured with CD40L before exposure to CEA peptide, whereas optimal stimulation by RNA-transfected DCs occurs when the DCs are loaded with CEA RNA before maturation with CD40L.
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Affiliation(s)
- M A Morse
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
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Abstract
Presentation of MHC class I antigens by professional antigen-presenting cells (APC) is an important pathway in priming cytotoxic T lymphocyte responses in vivo. This study sought to identify the nature of the professional APC responsible for indirect class I presentation by examining a special feature of professional APC, namely their ability to process exogenous forms of antigen for class I presentation. Incubation of highly purified bone marrow-derived precursor cells with chicken ovalbumin (OVA) led to the efficient presentation of the major class I-restricted OVA determinant by mature dendritic cells (DC), but not by macrophages (Mphi) derived from the precursor population. DC as well as macrophages were, however, able to mediate class II presentation of OVA, suggesting that macrophages were deficient in class I processing but not in capturing exogenous OVA. The majority of mature DC, i.e. over 80 %, generated from the precursor cells pulsed with OVA, presented the class I OVA epitope. Upon maturation, class I presentation of OVA by DC was greatly reduced, suggesting that class I processing of exogenous antigen is modulated during DC maturation in a manner similar to class II antigen processing. This study shows that bone marrow-derived DC/ME progenitors capture exogenous antigen for class I presentation, and that cells of the DC lineage can be functionally distinguished from cells of the macrophage lineage based on their ability to process exogenous antigen for class I presentation.
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Affiliation(s)
- D A Mitchell
- Department of Immunology and the Center for Genetic and Cellular Therapies, Duke University Medical Center, Durham 27710, USA
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Nair SK, Boczkowski D, Morse M, Cumming RI, Lyerly HK, Gilboa E. Induction of primary carcinoembryonic antigen (CEA)-specific cytotoxic T lymphocytes in vitro using human dendritic cells transfected with RNA. Nat Biotechnol 1998; 16:364-9. [PMID: 9555728 DOI: 10.1038/nbt0498-364] [Citation(s) in RCA: 323] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dendritic cells (DC) generated from the peripheral blood mononuclear cells of healthy individuals or from cancer patients transfected with carcinoembryonic antigen (CEA) mRNA stimulate a potent CD8+ cytotoxic T lymphocyte (CTL) response in vitro. DCs are effectively sensitized with RNA in the absence of reagents commonly used to facilitate mammalian cell transfection. RNA encoding a chimeric CEA/LAMP-1 lysosomal targeting signal enhances the induction of CEA-specific CD4+ T cells, providing a strategy to induce T-help that may be necessary to generate and/or maintain an optimal CD8+ CTL response in vivo. CEA RNA-transfected DCs also serve as effective targets in cytotoxicity assays, thus providing a general method for inducing, as well as measuring, CEA-specific CTL responses across a broad spectrum of HLA haplotypes.
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Affiliation(s)
- S K Nair
- Center for Genetic and Cellular Therapies, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
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