title: Improvement of the Oryza sativa Nipponbare reference genome using next generation sequence and optical map data.
abstract: BACKGROUND
  Rice research has been enabled by access to the high quality reference genome sequence generated in 2005 by the International Rice Genome Sequencing Project (IRGSP). To further facilitate genomic-enabled research, we have updated and validated the genome assembly and sequence for the Nipponbare cultivar of Oryza sativa (japonica group).
  
  
  RESULTS
  The Nipponbare genome assembly was updated by revising and validating the minimal tiling path of clones with the optical map for rice. Sequencing errors in the revised genome assembly were identified by re-sequencing the genome of two different Nipponbare individuals using the Illumina Genome Analyzer II/IIx platform. A total of 4,886 sequencing errors were identified in 321 Mb of the assembled genome indicating an error rate in the original IRGSP assembly of only 0.15 per 10,000 nucleotides. A small number (five) of insertions/deletions were identified using longer reads generated using the Roche 454 pyrosequencing platform. As the re-sequencing data were generated from two different individuals, we were able to identify a number of allelic differences between the original individual used in the IRGSP effort and the two individuals used in the re-sequencing effort. The revised assembly, termed Os-Nipponbare-Reference-IRGSP-1.0, is now being used in updated releases of the Rice Annotation Project and the Michigan State University Rice Genome Annotation Project, thereby providing a unified set of pseudomolecules for the rice community.
  
  
  CONCLUSIONS
  A revised, error-corrected, and validated assembly of the Nipponbare cultivar of rice was generated using optical map data, re-sequencing data, and manual curation that will facilitate on-going and future research in rice. Detection of polymorphisms between three different Nipponbare individuals highlights that allelic differences between individuals should be considered in diversity studies.
authors.affiliation: Agrogenomics Research Center, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki, 305-8602, Japan. taitoh@affrc.go.jp.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kawahara
authors.forename: Melissa
authors.initials: M
authors.lastname: de la Bastide
authors.forename: John P
authors.initials: JP
authors.lastname: Hamilton
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kanamori
authors.forename: W Richard
authors.initials: WR
authors.lastname: McCombie
authors.forename: Shu
authors.initials: S
authors.lastname: Ouyang
authors.forename: David C
authors.initials: DC
authors.lastname: Schwartz
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Tanaka
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Wu
authors.forename: Shiguo
authors.initials: S
authors.lastname: Zhou
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Childs
authors.forename: Rebecca M
authors.initials: RM
authors.lastname: Davidson
authors.forename: Haining
authors.initials: H
authors.lastname: Lin
authors.forename: Lina
authors.initials: L
authors.lastname: Quesada-Ocampo
authors.forename: Brieanne
authors.initials: B
authors.lastname: Vaillancourt
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Sakai
authors.forename: Sung Shin
authors.initials: SS
authors.lastname: Lee
authors.forename: Jungsok
authors.initials: J
authors.lastname: Kim
authors.forename: Hisataka
authors.initials: H
authors.lastname: Numa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Itoh
authors.forename: C Robin
authors.initials: CR
authors.lastname: Buell
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsumoto