COMPARATIVE SEQUENCE ANALYSIS OF BARLEY ESTs AND RICE GENOME

¹ Research Institute for Bioresources, Okayama Univ., Kurashiki, 710-0046, Japan

² National Institute of Genetics, Mishima, 411-8540, Japan

Homology analysis of barley EST sequences generated at Okayama University was performed against rice genome sequences (RiceGAAS http://ricegaas.dna.affrc.go.jp/). The result showed that 44% and 70% of the total barley unigenes were hit with rice genome sequences under scores of e-30 and e-5 of blastn, respectively. The same procedure was applied on the rice full-length cDNA sequences (KOME http://cdna01.dna.affrc.go.jp/cDNA/). The similarities were found as 50% and 77% under e-30 and e-5 of blastn, respectively. To confirm the spectrum of unigene sets of Okayama EST collection, barley unigene sequences provided by TIGR Gene Index (http://www.tigr.org/tdb/tgi/) were searched by blastn (e-5) with both rice databases and showed homologies of 70% (RiceGAAS) and 59% (KOME), respectively. These results suggested that there might be a number of genes which exists only in barley but not in rice. At the same time, barley ESTs having homology with rice genome could be mapped on rice linkage maps based on the sequence homology (http://www.shigen.nig.ac.jp/barley/). By the combination with barley EST map, this homology map can be used as powerful tool to introduce rice genome information into barley.