부산대학교 도서관

A 53-bp DNA, ABRC1, with abscisic acid (ABA) responsive and coupling elements, was inserted into the 35S promoter controlling the expression of β-glucuronidase (GUS) gene, and its regulation on the transient expression of the GUS gene in tobacco protoplast was employed to examine the functions of ABA within plant cells. Two repeats of ABRC1 in its right orientation were ABA inducible in the 800-bp full-length and in the 90-bp minimal 35S promoters. However, neither methyl jasmonate nor salicylic acid induced the 35S promoter with ABRC1 elements. Applying okadaic acid, a protein phosphatase inhibitor, and staurosporine, a protein kinase inhibitor, revealed that the action of either dephosphorylated protein(s) or phosphorylated protein(s) enhanced GUS expression from the 35S promoter that contains ABRC1 elements. Nevertheless, the presence of both dephosphorylated protein(s) and other phosphorylated protein(s) may interfere in the transcription of 35S promoter alone. Conclusively, multiple pathways regulate the 35S promoter with the ABRC1 elements. [Copyright &y& Elsevier]