Characterization of an ethylene‐induced esterase gene isolated from Citrus sinensis by competitive hybridization

Abstract

A simple new method, competitive hybridization, for identification of differentially regulated genes was used to isolate novel genes induced by ethylene in citrus (Citrus sinensis [L.] Osbeck cv. Shamouti) leaves. One of the isolated genes, an ethylene-induced esterase gene (EIE), was further characterized. The deduced protein sequence of this gene shows a similarity to those of several plant alpha/beta hydrolase gene family members, which are known to be involved in secondary metabolism. Northern blot analysis demonstrated that EIE mRNA was induced by ethylene within 4 h and accumulated to a very high level 24 h after the initiation of ethylene treatment. Induction of EIE by ethylene could be counteracted by 1-methylcyclopropene, a potent ethylene perception inhibitor, indicating that the expression of EIE is ethylene-dependent. The bacterially expressed protein of EIE was recognized by antiserum against Pir7b, a naphthol AS esterase induced in rice by the non-host pathogen, Pseudomonas syringae pv. syringae. The EIE protein was identified in ethylene-treated leaves using anti-Pir7b antibodies. An alpha-naphthyl acetate esterase accumulated concomitantly with the increase in EIE protein in ethylene-treated citrus leaves. An enzyme activity assay followed by western analysis confirmed that the esterase was EIE.

Stress-Related Proteins Are Specifically Expressed under Non-Stress Conditions in the Overwinter Buds of the Gentian Plant Gentiana triflora

“…Their substrates have been shown to include methyl esters of jasmonic acid (JA), abscisic acid (ABA), indole-3-acetic acid (IAA) and fatty acids. W14 and W15 proteins exhibited higher homologies to ethylene-induced esterase from Citrus sinensis (Zhong et al 2001), and partial amino acid sequences of methyljasmonate (MeJA) esterase from tomato (Lycopersicon esculentum) (Stuhlfelder et al 2002). The latter enzyme cleaves MeJA to generate JA, both of which are known to be signal compounds which respond to wounding and pathogen attack (Creelman et al 1992, Gundlach et al 1992.…”

“…Different amino acid sequences of the two proteins were also confirmed at the cDNA nucleotide sequence level (data not shown). Both proteins are considered to be members of an α/β hydrolase super family, since, in addition to sequence similarities, a putative catalytic triad (serine, aspartic acid and histidine, Ollis et al 1992, Zhong et al 2001 through which the enzymes hydrolyse their substrates was also present at positions similar to the other enzyme members (Table 1 and Fig. 3).…”

Metabolic, Genomic, and Biochemical Analyses of Glandular Trichomes from the Wild Tomato SpeciesLycopersicon hirsutumIdentify a Key Enzyme in the Biosynthesis of Methylketones

“…In addition, this peptide is similar to several proteins with no proven function, all considered to be part of the large a/b-hydrolase fold proteins (Waspi et al, 1998;Zhong et al, 2001;Marshall et al, 2003). This cDNA was represented only once (0.04%; accession number AW617364) in the LA1777 gland EST database.…”

“…These include, in addition to PNAE and tomato MJE, potato (Solanum tuberosum) MJE (accession number AY684102) and PIR7, a protein from rice (Oryza sativa) that was shown to have esterase activity with artificial substrates (Waspi et al, 1998). In addition, the tobacco (Nicotiana tabacum) SABP2 protein, which has recently been shown to be methyl salicylate esterase (Forouhar et al, 2005), and an uncharacterized protein encoded by an ethyleneinduced citrus EST (Zhong et al, 2001), as well as 20 proteins encoded in the Arabidopsis genome, show similarity to MKS1 (Figure 12). PIR7, PNAE, SABP2, and MJE all appear to have defense-related functions.…”

Respuesta de los frutos cítricos a las bajas temperaturas: estudio mediante micromatrices

“…También se halló inducción de un homólogo al receptor EIN4. Es interesante el aumento de expresión del gen esterasa inducible por ET, homólogo al gen de Citrus sinensis que se induce fuertemente en hojas tratadas con ET acompañado del aumento de actividad enzimática (Zhong et al, 2001). Además, este gen incrementa débilmente su expresión tras una herida.…”