DNA repair and crossing over favor similar chromosome regions as discovered in radiation hybrid of Triticum

BMC Genomics

Research Article

Harcharan S Dhaliwal¹  Gursharn S Randhawa²  Anne M Denton³  Omar Al-Azzam³  Vijay K Tiwari⁴  Harindra S Balyan⁵  Pushpendra K Gupta⁵  Sachin Kumar⁵  Aakash Goyal⁵  Wojciech P Pawlowski⁶  Ajay Kumar⁷  Shahryar F Kianian⁷  Muhammad J Iqbal⁷  Filippo M Bassi⁷  Monika Michalak de Jimenez⁷  Andrzej Kilian⁸  Eric Huttner⁸  Etienne Paux⁹  Catherine Feuillet⁹  Munevver Dogramaci^1,10  Yong Q Gu^1,11 

[1] Akal School of Biotechnology, Eternal University, 173101, Baru Sahib, India;Department of Biotechnology, Indian Institute of Technology, 247667, Roorkee, India;Department of Computer Science, North Dakota State University, 58102, Fargo, ND, USA;Department of Crop and Soil Science, Oregon State University, 97331, Corvallis, OR, USA;Department of Genetics and Plant Breeding, Ch. Charan Singh University, 25004, Meerut, India;Department of Plant Breeding and Genetics, Cornell University, 14853, Ithaca, NY, USA;Department of Plant Sciences, North Dakota State University, 58102, Fargo, ND, USA;Diversity Arrays Technology Pty Ltd, 2600, Yarralumla, ACT, Australia;INRA-UBP 1095, Genetics Diversity and Ecophysiology of Cereals, 63100, Clermont-Ferrand, France;USDA-ARS, Biosciences Research Laboratory, 58102, Fargo, ND, USA;USDA-ARS, Western Regional Research Center, 94710, Albany, CA, USA;

关键词: Non homologous end joining;    Physical mapping;    Gamma radiation;    Deletion mutant;    Chromatin;    Wheat chromosome 3B;    Radiation hybrid;   

DOI  :  10.1186/1471-2164-13-339

 received in 2012-05-09, accepted in 2012-07-07,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundThe uneven distribution of recombination across the length of chromosomes results in inaccurate estimates of genetic to physical distances. In wheat (Triticum aestivum L.) chromosome 3B, it has been estimated that 90% of the cross over events occur in distal sub-telomeric regions representing 40% of the chromosome. Radiation hybrid (RH) mapping which does not rely on recombination is a strategy to map genomes and has been widely employed in animal species and more recently in some plants. RH maps have been proposed to provide i) higher and ii) more uniform resolution than genetic maps, and iii) to be independent of the distribution patterns observed for meiotic recombination. An in vivo RH panel was generated for mapping chromosome 3B of wheat in an attempt to provide a complete scaffold for this ~1 Gb segment of the genome and compare the resolution to previous genetic maps.ResultsA high density RH map with 541 marker loci anchored to chromosome 3B spanning a total distance of 1871.9 cR was generated. Detailed comparisons with a genetic map of similar quality confirmed that i) the overall resolution of the RH map was 10.5 fold higher and ii) six fold more uniform. A significant interaction (r = 0.879 at p = 0.01) was observed between the DNA repair mechanism and the distribution of crossing-over events. This observation could be explained by accepting the possibility that the DNA repair mechanism in somatic cells is affected by the chromatin state in a way similar to the effect that chromatin state has on recombination frequencies in gametic cells.ConclusionsThe RH data presented here support for the first time in vivo the hypothesis of non-casual interaction between recombination hot-spots and DNA repair. Further, two major hypotheses are presented on how chromatin compactness could affect the DNA repair mechanism. Since the initial RH application 37 years ago, we were able to show for the first time that the iii) third hypothesis of RH mapping might not be entirely correct.

【 授权许可】

Unknown   
© Kumar et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.