High expression of a rice homeobox inE. coli

Homeotic genes share a characteristic DNA segment, the homeobox, which encodes a defined domain of the homeotic protein-homeodomain which seems to mediate the binding to specific DNA sequences, whereby the homeotic protein exerts a gene regulatory function. In this study, the homeodomain encoded by the OSIH-1 (designated from Oryza sativa-Indica homeobox-1) homeobox of rice was overproduced in a expression vector in E. coli , as a form of inclusion body and analyzed by Western blotting and crossed-immunoreaction. Crossed-immunoreaction studies among OSIH-1, Kn-1 and Quox-1 indicate all three are homologous at the protein level. The OSIH-1 homeodomain is then to identify the homeotic target genes.