RESUMEN
Phloem-feeding aphids cause serious damage to plants. The mechanisms of plant-aphid interactions are only partially understood and involve multiple pathways, including phytohormones. In order to investigate whether salicylic acid (SA) is involved and how it plays a part in the defense response to the aphid Macrosiphoniella sanbourni, physiological changes and gene expression profiles in response to aphid inoculation with or without SA pretreatment were compared between the aphid-resistant Artemisia vulgaris 'Variegata' and the susceptible chrysanthemum, Dendranthema nankingense. Changes in levels of reactive oxygen species, malondialdehyde (MDA), and flavonoids, and in the expression of genes involved in flavonoid biosynthesis, including PAL (phenylalanine ammonia-lyase), CHS (chalcone synthase), CHI (chalcone isomerase), F3H (flavanone 3-hydroxylase), F3'H (flavanone 3'-hydroxylase), and DFR (dihydroflavonol reductase), were investigated. Levels of hydrogen peroxide, superoxide anions, MDA, and flavonoids, and their related gene expression, increased after aphid infestation and SA pretreatment followed by aphid infestation; the aphid-resistant A. vulgaris exhibited a more rapid response than the aphid-susceptible D. nankingense to SA treatment and aphid infestation. Taken together, our results suggest that SA could be used to increase aphid resistance in the chrysanthemum.
Asunto(s)
Áfidos/fisiología , Artemisia/efectos de los fármacos , Chrysanthemum/efectos de los fármacos , Proteínas de Plantas/genética , Ácido Salicílico/farmacología , Aciltransferasas/genética , Aciltransferasas/metabolismo , Oxidorreductasas de Alcohol/genética , Oxidorreductasas de Alcohol/metabolismo , Animales , Áfidos/patogenicidad , Artemisia/genética , Artemisia/metabolismo , Artemisia/parasitología , Chrysanthemum/genética , Chrysanthemum/metabolismo , Chrysanthemum/parasitología , Conducta Alimentaria/fisiología , Flavonoides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Parásitos , Liasas Intramoleculares/genética , Liasas Intramoleculares/metabolismo , Malondialdehído/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Fenilanina Amoníaco-Liasa/genética , Fenilanina Amoníaco-Liasa/metabolismo , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Especificidad de la EspecieRESUMEN
MSP130-related-2 is thought to play a role in bio-mineralization as revealed in Crassostrea gigas and sea urchins. In this study, an MSP130-related-2 gene was isolated from Hyriopsis cumingii (HcMSP130-related-2) and characterized for the first time. The HcMSP130-related-2 cDNA was 2307 bp in length and consisted of a 572-bp 5'-untranslated region (5'-UTR), a 1239-bp open reading frame encoding 430-amino acid residues, and a 439-bp 3'-UTR. The molecular weight of the peptide was predicted to be 48551.3 Da, with a theoretical isoelectric point of 4.78 and instability index of 32.74, indicating that the protein is stable. The HcMSP130-related-2 amino acid residues included a signal peptide and several potential N-glycosylation sites. NCBI BLAST analysis indicated that this full-length amino acid sequence showed the highest similarity with HcMSP130-related-2 from C. gigas (45%) and about 38% identity with that from SpMSP130-rel-2 and Strongylocentrotus purpuratus. A phylogenetic tree showed that HcMSP130-rel-2 clustered with MSP130 from C. gigas. HcMSP130-related-2 was expressed in various tissues, including the mantle, blood, gill, foot, liver, kidney, intestine, and muscle, with the highest transcripts found in the mantle. Quantitative real-time polymerase chain reaction was used to analyze the expression of the HcMSP130- related-2 gene in grass carp after inducing shell damage. HcMSP130- related-2 expression was upregulated significantly in the mantle within 7 days (P < 0.05) after damage; however, the expression remained unchanged in the adductor muscle tissues (P > 0.05). These data suggest that HcMSP130-related-2 might be involved in shell formation in H. cumingii.