Physiological and functional analysis of a family of tetracycline transporter-like proteins in Arabidopsis

• Applicant: Professor Dr. Norbert Sauer
• Subject Area: Plant Physiology
• Term: from 2007 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 41120332

During transcriptome analyses of the vascular tissue of Plantago major the cDNA of a tetracycline transporter-like (Tet-TP-like) protein has been identified. Quantitative RT-PCRs revealed that this gene is specifically expressed in the vasculature of Plantago major. Arabidopsis possesses a small family of three Tet-TP-like genes that are located next to each other on chromosome II (At2g16970, At2g16980, At2g16990) and a fourth, only distantly related and much smaller gene on chromosome V (At5g42210). The promoter of At2g16970, the gene most closely related to the Tet-TP-like gene from Plantago drives expression of the GUS-reporter gene with high specificity also only in the vasculature of Arabidopsis thaliana. A homozygous At2g16970 k.o.-line that carries T-DNA insertion in its 1st exon shows a severe phenotype that results in tiny rosettes that to not produce fertile seeds. In this project we aim to characterize the family of Tet-TP-like proteins of Arabidopsis thaliana and the Tet-TP-like protein from Plantago major. We will generate and analyze inducible amiRNA-lines, over-expressors of Tet-TP-like genes and promoter- GUS/GFP lines and will analyze these plants for macroscopic, microscopic and metabolite phenotypes. Moreover, we will generate specific antisera against the different Tet-TP-like proteins and perform transient expression analyses with GFPtagged cDNAs to determine the cell-specific and subcellular localization. Functional analyses will be performed in different heterologous expression systems (yeast and Xenopus).

• DFG Programme: Research Grants