The Arabidopsis thaliana CUTA gene encodes an evolutionarily conserved copper binding chloroplast pro-tein. Plant J 34: 856-867

Biology Department, Colorado State University, Room E 416, Fort Collins, CO 80523, USA.
The Plant Journal (Impact Factor: 5.97). 07/2003; 34(6):856-67. DOI: 10.1046/j.1365-313X.2003.01769.x
Source: PubMed


The Arabidopsis thaliana CUTA gene encodes a 182-amino-acid-long putative precursor of a chloroplast protein with high sequence similarity to evolutionarily conserved prokaryotic proteins implicated in copper tolerance. Northern analysis indicates that AtCUTA mRNA is expressed in all major tissue types. Analysis of cDNA clones and RT-PCR with total mRNA revealed alternative splicing of AtCUTA by retention of an intron. The intron-containing mRNA encodes a truncated 156-amino-acid protein as a result of stop codons in the included intron. The sequence of AtCutAp encoded by the fully spliced transcript suggests that the precursor consists of three domains: an N-terminal chloroplast transit sequence of 70 residues, followed by a domain with prokaryotic signal-sequence-like characteristics and finally the most conserved C-terminal domain. The N-terminal chloroplast transit sequence was functional to route a passenger protein into isolated pea chloroplasts with possible sorting to the envelope. Chloroplast localization was confirmed by Western blot analysis of isolated and fractionated chloroplasts. Recombinant AtCutA protein was expressed in Escherichia coli without the N-terminal 70-amino-acid chloroplast transit sequence. This recombinant AtCutAp was routed to the bacterial periplasm of E. coli. Purified recombinant AtCutAp is tetrameric and selectively binds Cu(II) ions with an affinity comparable to that reported for mammalian prion proteins.

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Available from: Jason Lee Burkhead
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    • "Arabidopsis has a homolog of the conserved CutA protein (Burkhead et al., 2003) and CutA has some structural resemblance to ATX (Arnesano et al., 2003). CutA binds Cu(II) in vitro and was detected in chloroplasts of overexpressing plants (Burkhead et al., 2003), but its location has not yet been verified by GFP fusions and a T-DNA knockout does not affect plastocyanin function. Research in Synechocystis PCC 6803 on Atx1 has shed light on the role of metallochaperones (Borrely et al., 2004). "
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    ABSTRACT: Copper (Cu) is a cofactor in proteins that are involved in electron transfer reactions and is an essential micronutrient for plants. Copper delivery is accomplished by the concerted action of a set of evolutionarily conserved transporters and metallochaperones. As a result of regulation of transporters in the root and the rarity of natural soils with high Cu levels, very few plants in nature will experience Cu in toxic excess in their tissues. However, low Cu bioavailability can limit plant productivity and plants have an interesting response to impending Cu deficiency, which is regulated by an evolutionarily conserved master switch. When Cu supply is insufficient, systems to increase uptake are activated and the available Cu is utilized with economy. A number of Cu-regulated small RNA molecules, the Cu-microRNAs, are used to downregulate Cu proteins that are seemingly not essential. On low Cu, the Cu-microRNAs are upregulated by the master Cu-responsive transcription factor SPL7, which also activates expression of genes involved in Cu assimilation. This regulation allows the most important proteins, which are required for photo-autotrophic growth, to remain active over a wide range of Cu concentrations and this should broaden the range where plants can thrive.
    Full-text · Article · May 2009 · New Phytologist
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    • "It has been also shown that the Arabidopsis gene, AtCOX17, encoding a protein that shares sequence similarity to the copper yeast chaperone COX17, might serve as a copper delivery protein in the assembly of a functional cytochrome oxidase complex in the mitochondria (Balandin & Castesana, 2002). More recently, the specific interaction with Cu(II) ions and its presence in the chloroplast has suggest that AtCutAp , derived from alternative splicing of the gene AtCUTA of Arabidopsis, has a role as a typical copper chaperone in the control of metal homeostasis in chloroplasts (Burkhead et al., 2003). In addition, the gene PAA1, a P-Type ATPase of Arabidopsis, has been demonstrated to be a critical component of a copper transport system responsible for cofactor delivery to chloroplast Cu/Zn superoxide dismutase (Shikanai et al., 2003), whereas PAA2 has been more recently shown to localize at the thylakoid membranes and mediate transport of copper to plastocyanin (Abdel-Ghany et al., 2005). "
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    Full-text · Article · Jul 2007 · Plant Biosystems
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    • "within the plant . The presence of putative Cu 2+ transporters in plants ( e . g . HMA1 ) suggests that additional mechanisms may exist for proper Cu delivery . In this sense , the Arabidopsis CUTA protein , which binds Cu 2+ and localizes to the intermem - brane chloroplastic space , has been proposed as a candidate for a Cu 2+ metallochaperone ( Burkhead et al . 2003 ) ."
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    Full-text · Article · Apr 2007 · Plant Cell and Environment
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