Deep sequencing of the Mexican avocado transcriptome, an ancient angiosperm with a high content of fatty acids

Abstract

BackgroundAvocado (Persea americana) is an economically important tropical fruit considered to be a good source of fatty acids. Despite its importance, the molecular and cellular characterization of biochemical and developmental processes in avocado is limited due to the lack of transcriptome and genomic information.ResultsThe transcriptomes of seeds, roots, stems, leaves, aerial buds and flowers were determined using different sequencing platforms. Additionally, the transcriptomes of three different stages of fruit ripening (pre-climacteric, climacteric and post-climacteric) were also analyzed. The analysis of the RNAseqatlas presented here reveals strong differences in gene expression patterns between different organs, especially between root and flower, but also reveals similarities among the gene expression patterns in other organs, such as stem, leaves and aerial buds (vegetative organs) or seed and fruit (storage organs). Important regulators, functional categories, and differentially expressed genes involved in avocado fruit ripening were identified. Additionally, to demonstrate the utility of the avocado gene expression atlas, we investigated the expression patterns of genes implicated in fatty acid metabolism and fruit ripening.ConclusionsA description of transcriptomic changes occurring during fruit ripening was obtained in Mexican avocado, contributing to a dynamic view of the expression patterns of genes involved in fatty acid biosynthesis and the fruit ripening process.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-1775-y) contains supplementary material, which is available to authorized users.

ETIQUETAS DE SECUENCIAS EXPRESADAS DIFERENCIALES DE FRUTOS DE AGUACATE RAZA MEXICANA (Persea americana Mill. var. drymifolia)

“…El análisis de ADNc de la biblioteca de la pulpa de fruto de la variedad drymifolia, revela la presencia de algunos transcritos que se encuentran de forma abundante como metaloteonina tipo 1, 2 y 3, oleosina, endoquitinasa, fructosa bisfosfatoaldolasa, entre otros (PLIEGO-ALFARO et al, 2013); sin embargo, ninguna de las secuencias obtenidas en este trabajo coinciden con estos, pudiendo ser posiblemente porque utilizamos genotipos diferentes a los utilizados en el estudio. A partir de la publicación del transcriptoma del aguacate específicamente de la variedad drymifolia por Ibarra-Laclette et al (2015), se cuenta con información sobre patrones de expresión de genes involucrados en la biosíntesis de ácidos grasos y el proceso de maduración del fruto, estos autores reportaron que el 80.94% de los unigenes mostraron alta identidad con al menos una proteína de planta de las que se encuentran disponibles en las bases de datos del NCBI, el resto de los unigenes no tienen función asignada. El agrupamiento jerárquico de los transcriptomas reflejó la similaridad de funciones entre los órganos, así los transcritos de semilla y fruto se agruparon (IBARRA-LACLETTE et al, 2015) y puede ser la explicación de que 31 de las ESTs aquí obtenidas, mostraron similitud con secuencias de Persea americana del proyecto del Genoma Floral.…”

“…La elucidación de las bases genéticas relacionadas con el desarrollo, la maduración y el almacenamiento del fruto de aguacate, así como las relacionadas con la resistencia o tolerancia a enfermedades, abrirá oportunidades de transferir estas características agronómicas deseables. Un avance importante en la identificación de genes de este cultivo es la publicación del transcriptoma de drymifolia realizada por Ibarra-Laclette et al (2015). En Nuevo León, México, existen genotipos cultivados y silvestres de drymifolia con características fenológicas y morfológicas contrastantes (ACOSTA et al, 2012;GUTIÉRREZ-DÍEZ et al, 2015;); la corta vida de anaquel de sus frutos no les permite competir contra variedades como Hass y Fuerte.…”

Factors associated with postharvest ripening heterogeneity of ‘Hass’ avocados (Persea americanaMill)

“…drymifolia for six different organs and three ripening stages has recently been published [79]. A total of 67,000 unigenes were annotated, allowing the identification of 34,128 proteins [79]. The data generated suggested that oil accumulation and fatty acid composition ceased as the fruit initiates ripening.…”

“…Additionally, the transcriptome of Persea americana var. drymifolia for six different organs and three ripening stages has recently been published [79]. A total of 67,000 unigenes were annotated, allowing the identification of 34,128 proteins [79].…”

Transcriptome (ESTs) of Avocado “Native” Mexicano Early Seed Development Shows Abundance of Regulatory, Antioxidant and Defense Genes

“…It belongs to the large plant family of Lauraceae, with approximately 2500-3000 species [1,2]. Avocado has been rapidly incorporated as a component of human diet in many countries [3]. Due to low cost, vigor of seedling growth and easy propagation, most of the countries are still using seeds to produce rootstocks for grafted avocado trees despite their genetic variability [4].…”