Submitted to: American Society of Plant Biologists Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/25/2004
Publication Date: 7/25/2004
Citation: Zinn, K.E., Liu, J., Uhde-Stone, C., Vance, C.P., Allan, D.L. 2004. Elucidation of cis-elements in white lupin phosphorus deficiency signaling [abstract]. American Society of Plant Biologists Annual Meeting, July 24-28, 2004, Orlando, FL. Abstract No. 195. Interpretive Summary:
Technical Abstract: Phosphorus (P) deficiency stress in white lupin results in tightly coordinated physiological and morphological responses that give rise to cluster roots. One approach to elucidating the signaling pathway for P-deficiency is to determine whether specific nucleotide motifs in the promoter region of P-responsive genes confer P-deficiency specific expression. We have isolated and sequenced the 5'-upstream putative promoters for four white lupin proteoid root P-deficiency induced genes including an acid phosphatase (LaAPase), a phosphate transporter (LaPT), a MYB transcription factor, and a multi-drug toxin efflux (MATE). A genomic clone for a Pho85-like gene is presently being isolated. Promoter deletion analysis of LaAPase has been conducted to verify P responsiveness of putative cis-elements. Promoter deletions were generated through PCR and ligated into the polylinker upstream of the GUS reporter gene in plasmid pBI101.2. The resulting promoter::GUS reporter constructs were transferred to A. tumefaciens and used to transform Arabidopsis via the floral dip method. Six different LaAP::GUS constructs (each differing by 300 base pairs) have been analyzed. A region of the LaAP promoter between -1081 and -702 was required for P-deficiency specific reporter gene activity. Further deletion analysis of that region of the promoter will be conducted to isolate a minimal motif that confers expression of the reporter gene in the -P condition. Also, promoter fidelity in white lupin hairy roots will be confirmed by transformation with promoter reporter genes via Agrobacterium rhizogenes. Similar promoter deletion experiments will be performed with the 5'-upstream putative reporter region of the Pho85-like gene.