Construction Of Comparative Genomics Database Of Gramineae

Gramineae species have economic and scientific research value.Deciphering the complex genome structure and linking duplicated genes to specific polyploidization events are important to understand the biology and evolution of Gramineae plants.An online database GGDB(http://www.grassgenome.com/)was constructed based on the results of a comparative genomics analysis of 29 Gramineae plants.The database can display,search and download a list of homologous genes between each Gramineae plant.The database also developed an interactive collinear comparison tool to demonstrate the important crop population of Gramineae.Using these tools and result maps,users can observe the structural changes of the genome and explore the effects of doubling events on the genome structure.In this paper,the genomes of 29 well-assembled Gramineae plants were compared and analyzed,and some results were obtained.(1)It was found that chromosome breakage,loss,and fusion occurred in Gramineae plants after the whole genome doubling event,especially in corn(Zea mays)and other species that had undergone specific genome doubling.(2)According to the synonymous nucleotide replacement rate(Ks)between homologous regions and whether or not to share chromosome breakpoints,the homologous fragments produced by different events were distinguished,and a hierarchical list of homologous genes was established,which provided a collinear reference for Gramineae genome-related research.(3)The whole genome doubling event led to gene loss and gene evolution rate change,which might accelerate the differentiation of Gramineae species.At the same time,nearly 1/3 of gene families in Gramineae plants were significantly expanded due to doubling events,and the correlation between gene family formation and polyploidy events was more significant in maize and other species.The results of this study will provide a valuable reference for the related research on the structural and functional evolution of Gramineae,and GGDB will provide a useful platform for understanding the genomic changes and functional innovation of Gramineae.Figure 14;Table 6;Reference 76...