Oct. 24-26, 2009, Yingjie Overseas Exchange Center, Peking University, Beijing, China中文版

Dynamic Genome Evolution of the Oryza Genomes

MingSheng Chen

Insitute of Genetics and Developmental Biology, CAS, China

Abstract

Comparative genomics is a powerful tool to decipher gene and genome evolution. Placing multiple genome comparisons in a phylogenetic context improves the sensitivity of evolutionary inferences. A large genomic region surrounding the MONOCULM1 (MOC1) locus was chosen for study in 14 Oryza species. Sequencing and annotation of 18 bacterial artificial chromosome clones for these species revealed highly conserved gene colinearity and structure in the MOC1 region. Since the Oryza radiation about 14 million years ago, differences in transposon amplification appear to be responsible for the different current sizes of the Oryza genomes. In the MOC1 region, transposons were only conserved between genomes of the same type. In addition to the conserved gene content, several apparent genes have been generated de novo or uniquely retained in the AA lineage. Large and apparently non-coding sequences flanking the MOC1 gene were observed to be under strong purifying selection. The allotetraploids Oryza alta and Oryza minuta were found to be products of recent polyploidization, less than 1.6 and 0.4 mya, respectively. In allotetraploids, pseudogenization of duplicated genes was common, caused by large deletions, small frameshifting insertions/deletions or nonsense mutations. Comparative sequence analysis of a few other genomic regions will be discussed as well.

Mingsheng Chen

Insitute of Genetics and Developmental Biology, CAS, China

Biography

Dr. Mingsheng Chen graduated from Nankai University, Tianjin, China in 1988. He received the Master Degree from the Institute of Genetics, Chinese Academy of Sciences, Beijing, China in 1991 and Ph. D. from Purdue University, West Lafayette, Indiana, USA in 1998. He conducted a postdoctoral research in University of California, San Diego, California, USA from 1999 to 2001. Then he worked as a research assistant professor in Clemson University Genomics Institute, Clemson, South Carolina, USA for about one year. He was hired as a principal investigator by the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences in 2002. Dr. Chen’s main research areas are plant comparative and evolutionary genomics, bioinformatics and molecular cloning of genes of agronomic import.