Analysis of the rice endosperm-specific globulin promoter in transformed rice cells

The rice globulin (Glb) promoter was analyzed for its ability to control the expression of the human lysozyme gene in transgenic rice grains. The expression of the human lysozyme gene under the control of the Glb promoter reached 23% total soluble protein, with an average of 13%. To search for important elements within the Glb promoter, we analyzed both 5' and internal deletions of the rice globulin promoter using a transient expression assay system. The promoter activity was decreased along with the progressive 5' deletions. Every internal deletion also showed a reduction in transcription activity. Our analyses indicate that multiple promoter elements dispersed throughout the 896-bp globulin promoter sequence contribute to the strong Glb promoter activity.