title: The expression patterns of bromelain and AcCYS1 correlate with blackheart resistance in pineapple fruits submitted to postharvest chilling stress.
abstract: Blackheart is a physiological disorder induced by postharvest chilling storage during pineapple fruit export shipping. The aim of this study was to check the involvement of bromelain, the cysteine protease protein family abundantly present in pineapple fruits, and AcCYS1, an endogenous inhibitor of bromelain, in the development of blackheart. For this we checked the response to postharvest chilling treatment of two pineapple varieties (MD2 and Smooth Cayenne) differing in their resistance to blackheart. Quantitative RT-PCR analyses showed that postharvest chilling treatment induced a down-regulation of bromelain transcript accumulation in both varieties with the most dramatic drop in the resistant variety. Regarding AcCYS1 transcript accumulation, the varieties showed opposite trends with an up-regulation in the case of the resistant variety and a down-regulation in the susceptible one. Taken together our results suggest that the control of bromelain and AcCYS1 expression levels directly correlates to the resistance to blackheart development in pineapple fruits.
authors.affiliation: IBIOS-UMR CNRS 7618 BIOEMCO, Université Paris Est Créteil (UPEC), 61 Avenue du Général de Gaulle, 94010 Créteil cedex 2, France; CIRAD-PRAM, Quartier Petite Morne, BP214, 97 285 Le Lamentin, Martinique.
authors.forename: Astrid-Kim
authors.initials: AK
authors.lastname: Raimbault
authors.forename: Yasmine
authors.initials: Y
authors.lastname: Zuily-Fodil
authors.forename: Alain
authors.initials: A
authors.lastname: Soler
authors.forename: Phillipe
authors.initials: P
authors.lastname: Mora
authors.forename: Maria H
authors.initials: MH
authors.lastname: Cruz de Carvalho
mesh_terms: D031230:Ananas / Q000235:genetics / Q000502:physiology*; D001963:Bromelains / Q000235:genetics* / Q000378:metabolism; D003080:Cold Temperature; D015891:Cystatins / Q000235:genetics* / Q000378:metabolism; D005638:Fruit / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D015891:Cystatins; D010940:Plant Proteins; D001963:Bromelains
keywords: AcCYS1; Act; Ananas comusus cystatin 1; Aprt; Blackheart; Bromelain; CP; Cyc; PCT; Pineapple; Postharvest chilling treatment; RII; SC; Smooth Cayenne; actin; adenine phophoribosyl transferase; cyclophilin; cysteine protease; ef-α; elongation factor 1-α; postharvest chilling treatment; relative injury index; β-tb; β-tubulin