Regulated Expression of a Gene-Fusion Product Derived from the Gene for Phytochrome I fromPisum sativumand theuidAGene fromE. coliin TransgenicPetunia hybrida

摘要

The 5′-upstream region (2.4 kb) of the gene for phytochrome I fromPisum sativum (phyl)was fused to theuidAgene fromEscherichia colithat encodesβ-glucuronidase (GUS). The resulting PHY-GUS fusion was introduced intoPetunia hybridaand was used as a reporter of the expression of thephyIgene which was recognized by GUS activity. The PHY-GUS fusion was expressed at a relatively high level when transgenic plants were grown in the dark, while leaves and stems of light-grown plants showed background activity. Flowers of light-grown plants were shown to have significant levels of GUS activity but roots did not have such activity. When light-grown transgenic plants were transferred to the dark, they expressed the activity at levels that corresponded to those of dark-grown plants. Light treatment prior to growth in darkness revealed red/far-red reversibility of recovery of the activity. Thus, the 2.4-kb fragment from the 5′region of thephyIgene carries the information necessary for the light-repressible autoregula