%0 Journal Article
%T Mapping of Micro-Tom BAC-End Sequences to the Reference Tomato Genome Reveals Possible Genome Rearrangements and Polymorphisms
%A Erika Asamizu
%A Kenta Shirasawa
%A Hideki Hirakawa
%A Shusei Sato
%A Satoshi Tabata
%A Kentaro Yano
%A Tohru Ariizumi
%A Daisuke Shibata
%A Hiroshi Ezura
%J International Journal of Plant Genomics
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/437026
%X A total of 93,682 BAC-end sequences (BESs) were generated from a dwarf model tomato, cv. Micro-Tom. After removing repetitive sequences, the BESs were similarity searched against the reference tomato genome of a standard cultivar, ¡°Heinz 1706.¡± By referring to the ¡°Heinz 1706¡± physical map and by eliminating redundant or nonsignificant hits, 28,804 ¡°unique pair ends¡± and 8,263 ¡°unique ends¡± were selected to construct hypothetical BAC contigs. The total physical length of the BAC contigs was 495, 833, 423£¿bp, covering 65.3% of the entire genome. The average coverage of euchromatin and heterochromatin was 58.9% and 67.3%, respectively. From this analysis, two possible genome rearrangements were identified: one in chromosome 2 (inversion) and the other in chromosome 3 (inversion and translocation). Polymorphisms (SNPs and Indels) between the two cultivars were identified from the BLAST alignments. As a result, 171,792 polymorphisms were mapped on 12 chromosomes. Among these, 30,930 polymorphisms were found in euchromatin (1 per 3,565£¿bp) and 140,862 were found in heterochromatin (1 per 2,737£¿bp). The average polymorphism density in the genome was 1 polymorphism per 2,886£¿bp. To facilitate the use of these data in Micro-Tom research, the BAC contig and polymorphism information are available in the TOMATOMICS database. 1. Introduction Tomato (Solanum lycopersicum) is one of the most important vegetable crops cultivated worldwide. Tomato has a diploid (2n = 2x = 24) and relatively compact genome of approximately 950£¿Mb [1]. Recently, its genome has been completely sequenced by the international genome sequencing consortium [2]. Genetic linkage maps of tomato have been created by crossing cultivated tomato (S. lycopersicum) with several wild relatives, S. pennellii, S. pimpinellifolium, S. cheesmaniae, S. neorickii, S. chmielewskii, S. habrochaites, and S. peruvianum [3]. Introgression lines generated from a cross between S. lycopersicum and S. pennellii have contributed to the isolation of important loci and quantitative trait loci (QTLs) related to fruit size by utilizing DNA markers on the Tomato-EXPEN 2000 genetic map [4¨C9]. Such interspecies genetic mapping is effective because the divergent genomes provide many polymorphic DNA markers. In contrast, intraspecies mapping is less popular in tomato because of the low genetic diversity within cultivated tomatoes that has resulted from the domestication process and subsequent modern breeding [10]. Recently, we developed SNP, simple sequence repeat (SSR), and intronic polymorphic markers using publicly
%U http://www.hindawi.com/journals/ijpg/2012/437026/