Abstract
We previously reported our nuclear proteome analysis in which 643 and 399 proteins had been identified using rice nuclear and nucleic acids-associated proteins, respectively. Here we show an application of the rice nuclear proteome to screening of novel nuclear proteins that play evolutionarily conserved roles in sugar signaling. By scrutiny of identified proteins, the identified proteins were found to include OsHXK6, a recently identified sugar sensor in rice. Furthermore, we identified two WD40 repeat and one armadillo repeat?containing proteins as candidates for evolutionarily conserved proteins for sugar responses, because Arabidopsis databases suggested that expressions of the gene for Arabidopsis orthologues are up-regulated by glucose. RT-PCR analysis revealed that the genes for these proteins were also up-regulated by glucose in rice, and nuclear localization of these proteins were suggested by the experiment using GFP. Thus, these proteins might be novel nuclear proteins that play evolutionarily conserved roles in sugar signaling.
