Molecular cloning and expression of a cDNA encoding 1‐aminocyclopropane‐1‐carboxylate (ACC) oxidase from apricot fruit (Prunus armeniaca)

Abstract

Little is known on gene expression during ripening of apricot fruit (Prunus armeniaca cv. Bergeron), in particular for the enzymes involved in ethylene biosynthesis. ACC oxidase (EC 1.4.3) catalyses the last step of the ethylene biosynthesis pathway in higher plants. Based on sequence conservation of ACC oxidases, a reverse transcriptase‐polymerase chain reaction (RT‐PCR) experiment was carried out to synthesize a homologous ACC oxidase probe from apricot fruit. This probe was further used to isolate a full length ACC oxidase cDNA, Pa‐ACO, from a ripe fruit cDNA library. Pa‐ACO is 1 236 bp long and contains a single open reading frame encoding a mature peptide of 319 amino acids with a calculated molecular mass of 36.17 kDa and a pI of 5.07. Immunoblot analysis allowed us to associate a 40 kDa protein to apricot fruit ACC oxidase. Pa‐ACO belongs to a multi‐gene family, is fruit specific and is transcriptionally regulated during ripening of apricot fruit.

Transcriptomic study of apricot fruit (Prunus armeniaca) ripening among 13 006 expressed sequence tags

“…3). Quantitative PCR was not performed on polyphenol oxidase and ACC oxidase, because electronic Northern data was consistent with previous observations (Chevalier et al 1999, Mbéguié‐Mbéguié et al 1999) and the two pectin methyl esterase inhibitors.…”

“…Unidirectional cDNA libraries were constructed from apricot fruits harvested at 89 (green), 107 (half‐ripe), and 117 (ripe) days after anthesis (Mbéguié‐Mbéguié et al 1999). The green stage corresponded to the end of stone hardening, the half‐ripe stage to the onset of ethylene production, ethylene was detectable 3 days after (data not shown), and the ripe stage to the maximum in sucrose accumulation.…”

“…Total RNA was extracted from the pulp of the fruit according to the modified method of Wan and Wilkins (1994) (Mbéguié‐Mbéguié et al 1999). Seven grams of frozen tissue powdered in liquid nitrogen was mixed with 0.46 g of Diethyldithiocarbamic acid.…”

“…However, in spite of its economic importance (global production of 2.7 million metric tons in 2004, http://www.faostat.fao.org/), the identification of genes controlling fruit quality or problematic agronomic traits such as elevated sensitivity towards diseases or limited capacity for adaptation of most cultivars to pedo‐climatic conditions has been extremely limited. Before this work, less than 100 sequences were available in GenBank, including microsatellites or cDNAs related to self‐incompatibility or fruit ripening (Mbéguié‐Mbéguié et al 1999). By contrast, 308 sequences and 10 226 expressed sequence tags (ESTs) became recently available on peach.…”

Identification and characterization of transcripts differentially expressed during development of apricot (Prunus armeniaca L.) fruit

“…In apricot, studies on biochemical and molecular mechanisms that control ripening are only beginning [7,[31][32][33]. As part of a general project aimed at unraveling the mechanisms underlying the ripening process in the stone fruits, we aim to identify and clone genes differentially expressed during ripening and correlate their behavior to traits of agronomic interest.…”