title: Systemic induction of a Capsicum chinense nitrate reductase by the infection with Phytophthora capsici and defence phytohormones.
abstract: The mRNA differential display technique was used to identify genes from Habanero pepper (Capsicum chinense Jacq.) seedlings whose expression is modified systemically by infection with the oomycete Phytophthora capsici L. Experiments with different oligonucleotide primer combinations revealed that no single gene was synthesised de novo. Instead, the quantitative accumulation of multiple transcripts was found. From these transcripts, levels of a nitrate reductase (Capsicum chinense nitrate reductase, CcNR), which has a high percentage of identity with other Solanaceae NRs, showed a consistent increase a few hours after inoculation (hai) with P. capsici. Reverse northern blotting revealed the existence of basal levels of CcNR transcripts in different adult tissues; however, systemic levels rose dramatically after spraying seedlings with salicylic acid (SA) and ethephon (ET) but not with methyl jasmonate (MeJa). Both P. capsici and defence phytohormones (DP) also modified NR enzymatic activity (nitrite:NAD(+) oxidoreductase; EC 1.7.1.1) with similar kinetics. Because the application of DP induced and activated the CcNR differentially, it is possible that the activity of CcNR is related to a specific host defence response.
authors.affiliation: Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, AC, Calle 43 No. 130, colonia Chuburná de Hidalgo, Mérida 97200, Yucatán, Mexico.
authors.forename: María Goretty
authors.initials: MG
authors.lastname: Caamal-Chan
authors.forename: Ramón
authors.initials: R
authors.lastname: Souza-Perera
authors.forename: José Juan
authors.initials: JJ
authors.lastname: Zúñiga-Aguilar
mesh_terms: D000085:Acetates / Q000494:pharmacology; D002212:Capsicum / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000382:microbiology*; D003517:Cyclopentanes / Q000494:pharmacology; D004789:Enzyme Activation; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D050901:Nitrate Reductase / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D009943:Organophosphorus Compounds / Q000494:pharmacology; D054883:Oxylipins / Q000494:pharmacology; D010838:Phytophthora / Q000472:pathogenicity*; D010935:Plant Diseases / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism*; D057865:Plant Immunity; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D010940:Plant Proteins / Q000032:analysis / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000302:isolation & purification; D020156:Salicylic Acid / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D009943:Organophosphorus Compounds; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D018749:RNA, Plant; C072239:methyl jasmonate; D050901:Nitrate Reductase; D020156:Salicylic Acid; C005073:ethephon