Identification and characterization of MtMTP1, a Zn transporter of CDF family, in the Medicago truncatula.
Zn is an essential micronutrient in plants, and the mechanisms of Zn homeostasis are under intensive study. In this report, we have identified MtMTP1, a Zn transporter of the CDF family in the legume model plant Medicago truncatula. The ORF of the MtMTP1 cDNA encodes a protein consisting of 407 amino acid residues with a predicted molecular mass of 45 kDa. Like other metal tolerance proteins (MTPs) in plants, heterologous expression of MtMTP1 can complement the Zn-susceptible zrc1 cot1 yeast double mutant. The expression pattern was studied by quantitative fluorescent PCR. The expression of MtMTP1 was detected in all vegetative organs with the highest level of expression observed in leaves. With Zn supplementation its expression in roots was reduced while its expression in stems was increased in the first 2 days. No obvious changes were detected in leaves. Inoculation with Rhizobium meliloti down-regulated its expression in roots.
State Key Laboratory for Agro-Biotechnology, College of Biological Science, China Agricultural University, 100193 Beijing, China.
Mingliang
M
Chen
Xiaoye
X
Shen
Daofeng
D
Li
Lei
L
Ma
Jiangli
J
Dong
Tao
T
Wang
D000220:Adaptation, Biological; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary; D015536:Down-Regulation; D015870:Gene Expression; D017343:Genes, Plant; D046913:Medicago truncatula / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D008970:Molecular Weight; D009154:Mutation; D016366:Open Reading Frames; D010940:Plant Proteins; D018514:Plant Structures / Q000187:drug effects / Q000378:metabolism; D016133:Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D016962:Sinorhizobium meliloti; D015032:Zinc / Q000378:metabolism*
C076223:COT1 protein, S cerevisiae; D002352:Carrier Proteins; D027682:Cation Transport Proteins; D018076:DNA, Complementary; D026901:Membrane Transport Proteins; D010940:Plant Proteins; D029701:Saccharomyces cerevisiae Proteins; C088843:ZRC1 protein, S cerevisiae; D015032:Zinc