Abstract
The information of gene coexpression is valuable to predict gene functions. Several useful databases are available for this purpose including our databases, ATTED-II (for Arabidopsis and rice, http://atted.jp) and COXPRESdb (for human, mouse, rat, chicken, zebrafish, Drosohila and C. elegans, http://coxpresdb.jp). Several hundreds or thousands of microarray data are generally used for gene coexpression database. However microarray data in non-model species are still limited. Although several studies reported the number of required microarrays to construct reliable gene coexpression data, meaning of number of samples is still unclear. One of the reasons is different status of target data source. To overcome this problem, we analysis four species (human, mouse, rat and Arabidopsis) actually used in our coexpression databases.
