TY - JOUR A1 - Wu, Jun A1 - Wang, Zhiwen A1 - Shi, Zebin A1 - Zhang, Shu A1 - Ming, Ray A1 - Zhu, Shilin A1 - Khan, M. Awais A1 - Tao, Shutian A1 - Korban, Schuyler S. A1 - Wang, Hao A1 - Chen, Nancy J. A1 - Nishio, Takeshi A1 - Xu, Xun A1 - Cong, Lin A1 - Qi, Kaijie A1 - Huang, Xiaosan A1 - Wang, Yingtao A1 - Zhao, Xiang A1 - Wu, Juyou A1 - Deng, Cao A1 - Gou, Caiyun A1 - Zhou, Weili A1 - Yin, Hao A1 - Qin, Gaihua A1 - Sha, Yuhui A1 - Tao, Ye A1 - Chen, Hui A1 - Yang, Yanan A1 - Song, Yue A1 - Zhan, Dongliang A1 - Wang, Juan A1 - Li, Leiting A1 - Dai, Meisong A1 - Gu, Chao A1 - Wang, Yuezhi A1 - Shi, Daihu A1 - Wang, Xiaowei A1 - Zhang, Huping A1 - Zeng, Liang A1 - Zheng, Danman A1 - Wang, Chunlei A1 - Chen, Maoshan A1 - Wang, Guangbiao A1 - Xie, Lin A1 - Sovero, Valpuri A1 - Sha, Shoufeng A1 - Huang, Wenjiang A1 - Zhang, Shujun A1 - Zhang, Mingyue A1 - Sun, Jiangmei A1 - Xu, Linlin A1 - Li, Yuan A1 - Liu, Xing A1 - Li, Qingsong A1 - Shen, Jiahui A1 - Wang, Junyi A1 - Paull, Robert E. A1 - Bennetzen, Jeffrey L. A1 - Wang, Jun A1 - Zhang, Shaoling T1 - The genome of the pear (Pyrus bretschneideri Rehd.) Y1 - 2013/02/01 JF - Genome Research JO - Genome Research SP - 396 EP - 408 DO - 10.1101/gr.144311.112 VL - 23 IS - 2 UR - http://genome.cshlp.org/content/23/2/396.abstract N2 - The draft genome of the pear (Pyrus bretschneideri) using a combination of BAC-by-BAC and next-generation sequencing is reported. A 512.0-Mb sequence corresponding to 97.1% of the estimated genome size of this highly heterozygous species is assembled with 194× coverage. High-density genetic maps comprising 2005 SNP markers anchored 75.5% of the sequence to all 17 chromosomes. The pear genome encodes 42,812 protein-coding genes, and of these, ∼28.5% encode multiple isoforms. Repetitive sequences of 271.9 Mb in length, accounting for 53.1% of the pear genome, are identified. Simulation of eudicots to the ancestor of Rosaceae has reconstructed nine ancestral chromosomes. Pear and apple diverged from each other ∼5.4–21.5 million years ago, and a recent whole-genome duplication (WGD) event must have occurred 30–45 MYA prior to their divergence, but following divergence from strawberry. When compared with the apple genome sequence, size differences between the apple and pear genomes are confirmed mainly due to the presence of repetitive sequences predominantly contributed by transposable elements (TEs), while genic regions are similar in both species. Genes critical for self-incompatibility, lignified stone cells (a unique feature of pear fruit), sorbitol metabolism, and volatile compounds of fruit have also been identified. Multiple candidate SFB genes appear as tandem repeats in the S-locus region of pear; while lignin synthesis-related gene family expansion and highly expressed gene families of HCT, C3′H, and CCOMT contribute to high accumulation of both G-lignin and S-lignin. Moreover, alpha-linolenic acid metabolism is a key pathway for aroma in pear fruit. ER -