Dataset Information

Methylation and expression of amplified esterase genes in the aphid Myzus persicae (Sulzer).

ABSTRACT: Most populations of the aphid Myzus persicae have amplified genes (up to 80 copies) encoding the insecticide-detoxifying esterase E4. This paper reports the analysis of methylation of the E4 gene and its flanking DNA with the use of methylation-sensitive restriction enzymes, CpG profiling and bisulphite sequencing. In combination these show that E4 has 5-methylcytosine confined to CpG doublets, as previously shown for vertebrate genomes; this is the first such report for an insect gene. The methylation is present within the gene but absent from upstream regions, including the 5' CpG-rich region around the start of transcription, and from 3' flanking DNA. Methylated E4 genes are expressed; loss of the 5-methylcytosine is correlated with a loss of transcription, although this is not accompanied by a global loss of the 5-methylcytosine present in the aphid genome. These results suggest that the methylation of E4 has a positive role in expression, and call into question the widely held view that methylation in invertebrate genomes is confined to regions that do not contain genes and that methylation is always associated with gene silencing.

SUBMITTER: Field LM

PROVIDER: S-EPMC1221215 | biostudies-other | 2000 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:BackgroundAphid attack induces defense responses in plants activating several signaling cascades that led to the production of toxic, repellent or antinutritive compounds and the consequent reorganization of the plant primary metabolism. Pepper (Capsicum annuum L.) leaf proteomic response against Myzus persicae (Sulzer) has been investigated and analyzed by LC-MS/MS coupled with bioinformatics tools.ResultsInfestation with an initially low density (20 aphids/plant) of aphids restricted to a single leaf taking advantage of clip cages resulted in 6 differentially expressed proteins relative to control leaves (3 proteins at 2 days post-infestation and 3 proteins at 4 days post-infestation). Conversely, when plants were infested with a high density of infestation (200 aphids/plant) 140 proteins resulted differentially expressed relative to control leaves (97 proteins at 2 days post-infestation, 112 proteins at 4 days post-infestation and 105 proteins at 7 days post-infestation). The majority of proteins altered by aphid attack were involved in photosynthesis and photorespiration, oxidative stress, translation, protein folding and degradation and amino acid metabolism. Other proteins identified were involved in lipid, carbohydrate and hormone metabolism, transcription, transport, energy production and cell organization. However proteins directly involved in defense were scarce and were mostly downregulated in response to aphids.ConclusionsThe unexpectedly very low number of regulated proteins found in the experiment with a low aphid density suggests an active mitigation of plant defensive response by aphids or alternatively an aphid strategy to remain undetected by the plant. Under a high density of aphids, pepper leaf proteome however changed significantly revealing nearly all routes of plant primary metabolism being altered. Photosynthesis was so far the process with the highest number of proteins being regulated by the presence of aphids. In general, at short times of infestation (2 days) most of the altered proteins were upregulated. However, at longer times of infestation (7 days) the protein downregulation prevailed. Proteins involved in plant defense and in hormone signaling were scarce and mostly downregulated.

Project description:Myzus persicae (Sulzer) is an important insect pest in agriculture that has a very broad host range. Previous research has shown that the microbiota of insects has implications for their growth, development, and environmental adaptation. So far, there is little detailed knowledge about the factors that influence and shape the microbiota of aphids. In the present study, we aimed to investigate diet-induced changes in the microbiome of M. persicae using high-throughput sequencing of bacterial 16S ribosomal RNA gene fragments in combination with molecular and microbiological experiments. The transfer of aphids to different plants from the Solanaceae family resulted in a substantial decrease in the abundance of the primary symbiont Buchnera. In parallel, a substantial increase in the abundance of Pseudomonas was observed; it accounted for up to 69.4% of the bacterial community in M. persicae guts and the attached bacteriocytes. In addition, we observed negative effects on aphid population dynamics when they were transferred to pepper plants (Capsicum annuum L.). The microbiome of this treatment group showed a significantly lower increase in the abundance of Pseudomonas when compared with the other Solanaceae plant diets, which might be related to the adaptability of the host to this diet. Molecular quantifications of bacterial genera that were substantially affected by the different diets were implemented as an additional verification of the microbiome-based observations. Complementary experiments with bacteria isolated from aphids that were fed with different plants indicated that nicotine-tolerant strains occur in Solanaceae-fed specimens, but they were not restricted to them. Overall, our mechanistic approach conducted under controlled conditions provided strong indications that the aphid microbiome shows responses to different plant diets. This knowledge could be used in the future to develop environmentally friendly methods for the control of insect pests in agriculture.

Dataset Information

Methylation and expression of amplified esterase genes in the aphid Myzus persicae (Sulzer).

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets