A Novel Binary T-Vector with the <i>GFP</i> Reporter Gene for Promoter Characterization

<div><p>Several strategies have been developed to clone PCR fragments into desired vectors. However, most of commercially available T-vectors are not binary vectors and cannot be directly used for <i>Agrobacterium</i>-mediated plant genetic transformation. In this study, a novel binary T-vector was constructed by integrating two <i>Ahd</i>I restriction sites into the backbone vector pCAMBIA 1300. The T-vector also contains a <i>GFP</i> reporter gene and thus, can be used to analyze promoter activity by monitoring the reporter gene. On the other hand, identification and characterization of various promoters not only benefit the functional annotation of their genes but also provide alternative candidates to be used to drive interesting genes for plant genetic improvement by transgenesis. More than 1,000 putative pollen-specific rice genes have been identified in a genome-wide level. Among them, 67 highly expressed genes were further characterized. One of the pollen-specific genes <i>LOC_Os10g35930</i> was further surveyed in its expression patterns with more details by quantitative real-time reverse-transcription PCR (qRT-PCR) analysis. Finally, its promoter activity was further investigated by analyzing transgenic rice plants carrying the promoter::<i>GFP</i> cassette, which was constructed from the newly developed T-vector. The reporter <i>GFP</i> gene expression in these transgenic plants showed that the promoter was active only in mature but not in germinated pollens.</p>