RESUMO
Loquat (Eriobotrya japonica Lindl.), which originates from the cooler hill regions of southwestern China, is a typical subtropical evergreen tree. Loquat is one of the most important economic crops in China, but the available genomic information is very limited. Here, we present the first deep transcriptomic analysis of loquat. De novo assembly generated 116,723 contigs and 64,814 unigenes using Illumina sequencing technology. A total of 45,739 unigenes were annotated by Nr, GO, and COG datasets. In addition, we analyzed the gene expression profiles of loquat fruit under low temperature stress and 4017 differential expressed genes were identified. We found that the unigenes involved in the brassinosteroid biosynthesis and phosphatidylinositol signaling systems were upregulated, indicating that they have an important role in the resistance of plants to low temperature. Our results provide an invaluable resource for identification of specific genes and proteins involved in loquat development and response to low temperatures.
Assuntos
Temperatura Baixa , Eriobotrya/genética , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Transcriptoma , Biologia Computacional , Eriobotrya/metabolismo , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Fitosteróis/metabolismo , Transdução de SinaisRESUMO
Manual cultivar identification diagram is a new strategy for plant cultivar identification based on DNA markers, providing information to efficiently separate cultivars. We tested 25 pairs of apple EST-SSR primers for amplification of PCR products from loquat cultivars. These EST-SSR primers provided clear amplification products from the loquat cultivars, with a relatively high transferability rate of 84% to loquat; 11 pairs of primers amplified polymorphic products. After analysis of 24 red-fleshed loquat accessions, we found that only 7 pairs of primers could clearly separate all of them. A cultivar identification diagram of the 24 cultivars was constructed using polymorphic bands from the DNA fingerprints and EST-SSR primers. Any two of the 24 cultivars could be rapidly separated from each other, according to the polymorphic bands from the cultivars; the corresponding primers were marked in the correct position on the cultivar identification diagram. This red-flesh loquat cultivar identification diagram can separate the 24 red-flesh loquat cultivars, which is of benefit for loquat cultivar identification for germplasm management and breeding programs.
Assuntos
Cruzamento , Eriobotrya/genética , Repetições de Microssatélites/genética , DNA de Plantas , Eriobotrya/crescimento & desenvolvimento , Marcadores Genéticos/genética , Malus/genéticaRESUMO
RNA isolation is difficult in plants that contain large amounts of polysaccharides and polyphenol compounds. To date, no commercial kit has been developed for the isolation of high-quality RNA from tissues with these characteristics, especially for fruit. The common protocols for RNA isolation are tedious and usually result in poor yields when applied to recalcitrant plant tissues. Here an efficient RNA isolation protocol based on cetyltrimethylammonium bromide (CTAB) and two successive precipitations with 10 M lithium chloride (LiCl) was developed specifically for loquat fruits, but it was proved to work efficiently in other tissues of loquat and woody plants. The RNA isolated by this improved protocol was not only of high purity and integrity (A260/A280 ratios ranged from 1.90 to 2.04 and A260/A230 ratios were>2.0) but also of high yield (up to 720 µg on average [coefficient of variation=21%] total RNA per gram fresh tissue). The protocol was tested on loquat fruit (different stages of development, postharvest, ripening, and bruising), leaf, root, flower, stem, and bud; quince fruit and root; grapevine cells in liquid culture; and rose petals. The RNA obtained with this method is amenable to enzymatic treatments and can be efficiently applied for research on gene characterization, expression, and function.