Biodiv Sci ›› 2014, Vol. 22 ›› Issue (1): 51-65.  DOI: 10.3724/SP.J.1003.2014.13169

Special Issue: 基因组和生物多样性

• Orginal Article • Previous Articles     Next Articles

Genome evolution of Oryza

Tieyan Liu, Mingsheng Chen*()   

  1. State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101
  • Received:2013-07-19 Accepted:2013-10-14 Online:2014-01-20 Published:2014-02-10
  • Contact: Chen Mingsheng

Abstract:

The genus Oryza is composed of approximately 24 species. Wild species of Oryza contain a largely untapped resource of agronomically important genes. As an increasing number of genomes of wild rice species have been or will be sequenced, Oryza is becoming a model system for plant comparative, functional and evolutionary genomics studies. Comparative analyses of large genomic regions and whole-genome sequences have revealed molecular mechanisms involved in genome size variation, gene movement, genome evolution of polyploids, transition of euchromatin to heterochromatin and centromere evolution in the genus Oryza. Transposon activity and removal of transposable elements by unequal recombination or illegitimate recombination are two important factors contributing to expansion or contraction of Oryza genomes. Double-strand break repair mediated gene movement, especially non-homologous end joining, is an important source of non-colinear genes. Transition of euchromatin to heterochromatin is accompanied by transposable element amplification, segmental and tandem duplication of genic segments, and acquisition of heterochromatic genes from other genomic locations. Comparative analyses of multiple genomes dramatically improve the precision and sensitivity of evolutionary inference than single-genome analyses can provide. Further investigations on the impact of structural variation, lineage-specific genes and evolution of agriculturally important genes on phenotype diversity and adaptation in the genus Oryza should facilitate molecular breeding and genetic improvement of rice.

Key words: Oryza, comparative genomics, genome evolution, functional genomics