Identification of anther-specific gene expression from T-DNA tagging rice.

We have screened a total of 5,500 T-DNA tagging rice lines in which beta-glucuronidase (GUS) gene sequence was randomly inserted as a transgene into the plant genome. Histochemical GUS assays were carried out to select the T-DNA tagging rice lines that show its expression in anther. Of the tagging lines screened, three lines were found to express GUS specifically in the anther that is about 0.05%. Microscopic observation of the anther-expressed lines showed specific expression patterns of GUS in the anther, either gametophytic or sporophytic specificities. Southern blot analysis revealed that the integration copy number of the transgene was 2.3 in average. The detailed expression patterns were analyzed and discussed.