Talk:Os02g0725900

In this study, we identified all the genes, which encode HAP2, HAP3 and HAP5 subunits of the CCAAT-box binding complex in rice. In contrast to animal and yeast, which have only a single gene for each subunit of the HAP complex, rice has 10 genes for the HAP2 subunit, 11 genes for the HAP3 subunit and 7 genes for the HAP5 subunit. Arabidopsis also has multiple genes for each subunit. Because both the monocotyledonous plant rice and the dicotyledonous plant Arabidopsis have multiple genes for each of three subunits, this may be a general property for higher plants. Identification of several distinct cDNAs for each subunit in several plant species by the database searches supports this notion. OsHAP2, OsHAP3 and OsHAP5 genes were dispersed on five, seven and six chromosomes, respectively . Among the OsHAP genes, OsHAP3E and OsHAP3K, and OsHAP3G and OsHAP3J were located on the same chromosomes in the vicinity of each other. The phylogenetic analysis, however, showed that OsHAP3E and OsHAP3K were in different clades, and suggested that they are rather diverged members of the HAP3 family. In an OsHAP3G and OsHAP3J combination, the amino acid identity in the conserved domain was not very high (only 71%), and they do not share the characteristic stretches of amino acid residues in the non-conserved N- and C-terminus regions . Thus, they may not be pairs of recently duplicated genes. No other cluster of OsHAP genes was observed in the rice genome. Arabidopsis HAP (AtNF-Y) genes are also spread on all the five chromosomes.