|LOPEZ-MILLAN, ANA FLOR|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/15/2002
Publication Date: 7/15/2002
Citation: LOPEZ-MILLAN, A., ELLIS, D.R., GRUSAK, M.A. SEQUENCE ANALYSES, PHYLOGENETIC CHARACTERIZATION AND EXPRESSION PATTERN OF SEVERAL MEMBERS FROM THE ZIP FAMILY OF METAL ION TRANSPORTERS IN MEDICAGO TRUNCATULA. ABSTRACTS OF THE FIRST INTERNATIONAL CONFERENCE ON LEGUME GENOMICS AND GENETICS: TRANSLATION TO CROP IMPROVEMENT. 2002. p.88. ABSTRACT A1.
Technical Abstract: Several novel divalent metal transporters of the Zip family have been characterized in Arabidopsis thaliana. Zrt1, Zrt2, and Zip1-4 are probably Zn transporters, whereas Irt1 appears to play a role in Fe uptake. Because we are interested in metal homeostasis in legumes, we performed database searches to these genes and identified 24 ESTs in the model legume, Medicago truncatula, as probable homologs of the Zip transporter family. Each of the ESTs was obtained and sequenced; six of them contained full-length sequences of genes sharing more than 70% homology with Arabidopsis Zip family members. The genes from Medicago truncatula (MtZip's) were aligned and a phylogenetic tree for the family was constructed. The expression pattern for each gene was studied by RT-PCR in roots and leaves from plants grown under different metal supplies. MtZip5, MtZip4 and MtZip2 were upregulated under zinc deficiency in both roots and leaves. MtZIP5 also was upregulated in leaves under Mn deficiency and MtZip4 under Zn and Mn toxicities. MtZip3 was downregulated under Fe deficient conditions, while the expression of MtZip7 was unchanged under all treatments. We also will present and compare expression data for roots and leaves of a unique Medicago truncatula zinc mutant, raz, which requires additional zinc for more normal growth. This work was funded in part by USDA-ARS Cooperative Agreement No. 58-6250-1-003 and by USDA-CSREES-NRI Grant No. 0-35100-9365 to MAG.