Extraccion De Aceite

Plant Science 179 (2010) 499–509

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Plant Science
journal homepage: www.elsevier.com/locate/plantsci

Identification and expression analysis of castor bean (Ricinus communis) genes encoding enzymes from the triacylglycerol biosynthesis pathway
Alexandro Cagliari a , Márcia Margis-Pinheiro a,b , Guilherme Loss b , Alexandra Antunes Mastroberti c ,Jorge Ernesto de Araujo Mariath c , Rogério Margis a,b,∗
a

Departamento de Genética, Universidade Federal do Rio Grande do Sul, Brazil Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Brazil c Instituto de Biociências, Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Brazil
b

a r t i c l e

i n f o

a b s t r a c t
Castor bean (Ricinus communis)oil contains ricinoleic acid-rich triacylglycerols (TAGs). As a result of its physical and chemical properties, castor oil and its derivatives are used for numerous bio-based products. In this study, we survey the Castor Bean Genome Database to report the identification of TAG biosynthesis genes. A set of 26 genes encoding six distinct classes of enzymes involved in TAGs biosynthesis were identified.In silico characterization and sequence analysis allowed the identification of plastidic isoforms of glycerol-3-phosphate acyltransferase and lysophosphatidate acyltransferase enzyme families, involved in the prokaryotic lipid biosynthesis pathway, that form a cluster apart from the cytoplasmic isoforms, involved in the eukaryotic pathway. In addition, two distinct membrane bound diacylglycerolacyltransferase enzymes were identified. Quantitative expression pattern analyses demonstrated variations in gene expressions during castor seed development. A tendency of maximum expression level at the middle of seed development was observed. Our results represent snapshots of global transcriptional activities of genes encompassing six enzyme families involved in castor bean TAG biosynthesis thatare present during seed development. These genes represent potential targets for biotechnological approaches to produce nutritionally and industrially desirable oils. © 2010 Elsevier Ireland Ltd. All rights reserved.

Article history: Received 10 June 2010 Received in revised form 18 July 2010 Accepted 24 July 2010 Available online 1 August 2010 Keywords: Castor bean Lipid metabolism Lipidbiosynthesis Seed development Ricinoleate TAG

1. Introduction Triacylglycerols (TAGs) are the major storage lipids in living organisms. As a highly reduced form of carbon, they serve as an important energy reserve in plant seeds, providing for subsequent germination and seedling development. These storage lipids are of great nutritional and nutraceutical value and, thus, are a common source of edibleoils for human consumption and industrial purposes [1]. According to the current knowledge of castor seed TAG biosynthesis, oleic acid is synthesized in the plastid and then exported to the cytoplasm following the standard fatty acid biosynthesis pathway [2]. Oleic acid is activated to oleoyl-CoA in the cytoplasm and imported into the endoplasmic reticulum (ER) with the help of coenzyme A (CoA).In the ER, it undergoes a hydroxylation

∗ Corresponding author at: Centro de Biotecnologia, Prédio 43431, Sala 213, Universidade Federal do Rio Grande do Sul – Campus do Vale, Porto Alegre, CEP 91501-970 Rio Grande do Sul, Brazil. Tel.: +55 51 33087766. E-mail addresses: alexandrocagliari@yahoo.com.br (A. Cagliari), marcia.margis@ufrgs.br (M. Margis-Pinheiro), guilherme.loss@gmail.com (G. Loss),a mastroberti@yahoo.com (A.A. Mastroberti), jorge.mariath@me.com (J.E. de Araujo Mariath), rogerio.margis@ufrgs.br (R. Margis). 0168-9452/$ – see front matter © 2010 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.plantsci.2010.07.015

process, through the activity of the oleate hydroxylase (FAH12) enzyme, yielding ricinoleic acid (C18:1-OH) that is incorporated into a glycerol...