title: Copper-induced overexpression of genes encoding antioxidant system enzymes and metallothioneins involve the activation of CaMs, CDPKs and MEK1/2 in the marine alga Ulva compressa.
abstract: Transcriptomic analyses were performed in the green macroalga Ulva compressa cultivated with 10μM copper for 24h. Nucleotide sequences encoding antioxidant enzymes, ascorbate peroxidase (ap), dehydroascorbate reductase (dhar) and glutathione reductase (gr), enzymes involved in ascorbate (ASC) synthesis l-galactose dehydrogenase (l-gdh) and l-galactono lactone dehydrogenase (l-gldh), in glutathione (GSH) synthesis, γ-glutamate-cysteine ligase (γ-gcl) and glutathione synthase (gs), and metal-chelating proteins metallothioneins (mt) were identified. Amino acid sequences encoded by transcripts identified in U. compressa corresponding to antioxidant system enzymes showed homology mainly to plant and green alga enzymes but those corresponding to MTs displayed homology to animal and plant MTs. Level of transcripts encoding the latter proteins were quantified in the alga cultivated with 10μM copper for 0-12 days. Transcripts encoding enzymes of the antioxidant system increased with maximal levels at day 7, 9 or 12, and for MTs at day 3, 7 or 12. In addition, the involvement of calmodulins (CaMs), calcium-dependent protein kinases (CDPKs), and the mitogen-activated protein kinase kinase (MEK1/2) in the increase of the level of the latter transcripts was analyzed using inhibitors. Transcript levels decreased with inhibitors of CaMs, CDPKs and MEK1/2. Thus, copper induces overexpression of genes encoding antioxidant enzymes, enzymes involved in ASC and GSH syntheses and MTs. The increase in transcript levels may involve the activation of CaMs, CDPKs and MEK1/2 in U. compressa.
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, Alameda 3363, Santiago, Chile.
authors.forename: Daniel
authors.initials: D
authors.lastname: Laporte
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, Alameda 3363, Santiago, Chile.
authors.forename: Natalia
authors.initials: N
authors.lastname: Valdés
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, Alameda 3363, Santiago, Chile.
authors.forename: Alberto
authors.initials: A
authors.lastname: González
authors.affiliation: Laboratory of Coastal Toxicology, Center of Advanced Studies, University of Playa Ancha, Traslaviña 450, Viña del Mar, Chile.
authors.forename: Claudio A
authors.initials: CA
authors.lastname: Sáez
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, Alameda 3363, Santiago, Chile.
authors.forename: Antonio
authors.initials: A
authors.lastname: Zúñiga
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, Alameda 3363, Santiago, Chile.
authors.forename: Axel
authors.initials: A
authors.lastname: Navarrete
authors.affiliation: Centro de Biotecnología Vegetal, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Chile; FONDAP, Center for Genome Regulation, Universidad Andrés Bello, Chile.
authors.forename: Claudio
authors.initials: C
authors.lastname: Meneses
authors.affiliation: Marine Biotechnology Laboratory, Faculty of Chemistry and Biology, University of Santiago of Chile, Alameda 3363, Santiago, Chile. Electronic address: alejandra.moenne@usach.cl.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Moenne
mesh_terms: D020418:Algal Proteins / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism*; D002147:Calmodulin / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects*; D020869:Gene Expression Profiling; D005721:Glutamate-Cysteine Ligase / Q000235:genetics / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000235:genetics / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000737:chemistry / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D044445:Ulva / Q000201:enzymology / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D017871:Calcium-Calmodulin-Dependent Protein Kinases
chemical_list: D020418:Algal Proteins; D000975:Antioxidants; D002147:Calmodulin; D003300:Copper; D005721:Glutamate-Cysteine Ligase; D005978:Glutathione; D008668:Metallothionein; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D011494:Protein Kinases; D018749:RNA, Plant; D014874:Water Pollutants, Chemical; D017871:Calcium-Calmodulin-Dependent Protein Kinases
keywords: Antioxidant enzymes; Gene expression marine alga; Metallothioneins; Signaling; Ulva compressa