Chromosome painting of telomeric repeats reveals new evidence for genome evolution in peanut  

作　　者：DU Pei LI Li-na ZHANG Zhong-xin LIU Hua QIN Li HUANG Bing-yan DONG Wen-zhao TANG Feng-shou QI Zeng-jun ZHANG Xin-you 

机构地区：[1]State Key Laboratory of Crop Genetics and Germplasm Enhancement,Nanjing Agricultural University [2]Industrial Crops Research Institute,Henan Academy of Agricultural Sciences/Key Laboratory of Oil Crops in Huang-Huai-Hai Plains,Ministry of Agriculture/Henan Provincial Key Laboratory for Oil Crops Improvement [3]College of Agriculture,Henan University of Science and Technology

出　　处：《Journal of Integrative Agriculture》2016年第11期2488-2496,共9页农业科学学报（英文版）

基　　金：supported by the China Agriculture Research System(CARS-14);the Henan Provincial Agriculture Research System,China(S2012-05);the Major Technology Research and Development Program of Henan Province,China(141100110600)

摘　　要：Interspecific hybridization is an important approach to improve cultivated peanut varieties. Cytological markers such as tandem repeats will facilitate alien gene introgression in peanut. Telomeric repeats have also been frequently used in chromosome research. Most plant telomeric repeats are（TTTAGGG）n that are mainly distributed at the chromosome ends, although interstitial telomeric repeats（ITRs） are also commonly identified. In this study, the telomeric repeat was chromosomally localized in 10 Arachis species through sequential GISH（genomic in situ hybridization） and FISH（fluorescence in situ hybridization） combined with 4＇,6-diamidino-2-phenylindole（DAPI） staining. Six ITRs were identified such as in the centromeric region of chromosome Bi5 in Arachis ipa？nsis, pericentromeric regions of chromosomes As5 in A. stenosperma, Bho7 in A. hoehnei and Av5 in A. villosa, nucleolar organizer regions of chromosomes As3 in A. stenosperma and Adi3 in A. diogoi, subtelomeric regions of chromosomes Bho9 in A. hoehnei and Adu7 in A. duranensis, and telomeric region of chromosome Es7 in A. stenophylla. The distributions of the telomeric repeat, 5S r DNA, 45 S r DNA and DAPI staining pattern provided not only ways of distinguishing different chromosomes, but also karyotypes with a higher resolution that could be used in evolutionary genome research. The distribution of telomeric repeats, 5S r DNA and 45 S r DNA sites in this study, along with inversions detected on the long arms of chromosomes Kb10 and Bho10, indicated frequent chromosomal rearrangements during evolution of Arachis species.Interspecific hybridization is an important approach to improve cultivated peanut varieties. Cytological markers such as tandem repeats will facilitate alien gene introgression in peanut. Telomeric repeats have also been frequently used in chromosome research. Most plant telomeric repeats are（TTTAGGG）n that are mainly distributed at the chromosome ends, although interstitial telomeric repeats（ITRs） are also commonly identified. In this study, the telomeric repeat was chromosomally localized in 10 Arachis species through sequential GISH（genomic in situ hybridization） and FISH（fluorescence in situ hybridization） combined with 4＇,6-diamidino-2-phenylindole（DAPI） staining. Six ITRs were identified such as in the centromeric region of chromosome Bi5 in Arachis ipa？nsis, pericentromeric regions of chromosomes As5 in A. stenosperma, Bho7 in A. hoehnei and Av5 in A. villosa, nucleolar organizer regions of chromosomes As3 in A. stenosperma and Adi3 in A. diogoi, subtelomeric regions of chromosomes Bho9 in A. hoehnei and Adu7 in A. duranensis, and telomeric region of chromosome Es7 in A. stenophylla. The distributions of the telomeric repeat, 5S r DNA, 45 S r DNA and DAPI staining pattern provided not only ways of distinguishing different chromosomes, but also karyotypes with a higher resolution that could be used in evolutionary genome research. The distribution of telomeric repeats, 5S r DNA and 45 S r DNA sites in this study, along with inversions detected on the long arms of chromosomes Kb10 and Bho10, indicated frequent chromosomal rearrangements during evolution of Arachis species.

关 键 词：Arachis species inversion interstitial telomeric repeats KARYOTYPE 

分 类 号：S565.2[农业科学—作物学]