Project description:The Eurasian spruce bark beetle Ips typographus is known for its devasting attack on the host tree Picea abies, a common conifer in Europe. The beetle uses various pheromone components (2-methyl-3-buten-2-ol and cis-verbenol) for mass aggregation to overcome the tree defence compounds such as terpenes. Though this aggregation pheromone biosynthesis and respective precursors via terpenes detoxification mechanism was investigated for a few decades, gene-level understanding behind these biosynthesis pathways are uncertain yet in I. typographus. Though, applying Juvenile hormone (JH III) on the beetles have induced specific pheromone biosynthesis in many bark beetle species, irrespective of their life stage, it is not uniform found in all Ips species. While investigating pheromone biosynthesis among various life stages of I. typographus, we have also reported recently about the JHIII induction of aggregation pheromone biosynthesis from the gut tissue of the beetle. Thus, in this study, we have applied the concept of JHIII induction on I. typographus and analyzed the respective pheromone and possible biosynthesis precursors from via pathway gene families from the gut tissue of the beetle. A comparative approach from transcriptome and proteome study has revealed the mevalonate pathway genes including isoprenyl-di-phosphate synthase (IPDS) gene (Ityp09271) was upregulated over 5-fold change after JHIII induction in I. typographus. The identified IPDS is suspected to directly involve in 2-methyl-3-buten-2-ol, a vital aggregation pheromone of I. typographus. Added to that, a hydrolase gene family was found upregulated over 2-fold change, specifically in the male gut tissue after JHIII treatment. Furthermore, another vital gene family, CytochromeP450 have shown the upregulated (transcript) in the male gut tissue after treatment. Especially Previously reported CyP450 candidates Ityp3140 and Ityp03153 for pheromone compounds cis/trans- verbenol and ipsdienol biosynthesis respectively. Along with CyP450 candidates, the hydrolase gene candidates could possibly involve in braking down the detox compounds such as diglycosylated terpenes and stored wax esters (verbenyl oleate) from the gut possibly provided from the of the beetle body as a reservoir. An added metabolomic analysis has confirmed these compounds abundance was in the gut tissue. Especially, the abundance of the related fatty acid ester (verbenyl oleate) has reduced half in male gut tissue after the treatment. Hence, we have shed light on three possible genes from different families for the respective pheromone and its precursors biosynthesis after JHIII application over I. typographus. This approach would lead us to elucidate the molecular basis of stored pheromone biosynthesis and the derived knowledge from this study would lead to eco-friendly pest management for this aggressive pest. Key words: Ips typographus, bark beetle, pheromone biosynthesis, de novo, Juvenile hormone treatment.
Project description:Using 21K spruce microarray (that contains 21.8 thousand unique transcripts) we performed analysis of the transcriptome response of interior spruce (Picea glauca x engelmannii) inoculated with the spruce beetle (Dendroctonus rufipennis) vectored blue stain fungal pathogen Leptographium abietinum or treated with wounding. This microarray analysis revealed large transcriptome reorganization with close to 2000 transcripts (10% of the studied transcriptome) differentially expressed within two weeks of treatment, with the wounding response affecting close to 5% of the interior spruce transcriptome. RNA was isolated from the bark of interior spruce inoculated with Leptographium abietinum, treated with wounding, or untreated control for three time points (6h, 2days and 2 weeks). Three independent biological replicates were included for each treatment and each time point. Three hybridizations were performed for each comparison of different treatments (fungal, wounding, control) within each time point (6 hours, 2 days, 2 weeks) and one hybridization was performed for the comparison of the same treatments between time points (total 36 hybridizations/slides).
Project description:We performed a transcriptome analysis of interior spruce (Picea glauca x engelmannii) bark response to weevil (Pissodes strobi) feeding using 21.8K spruce microarray (that contains 21.8 thousand unique transcripts). This microarray study revealed a large rearrangement of the interior spruce bark transcriptome in response to weevil feeding involving differential expression of close to 20% of the studied transcriptome.
Project description:The present project deals with bark beetle gut total proteome from callow and black bark beetle, Ips typographus. The study aims to identify life stage-specific expression of gut proteins in bark beetles and their functional relevance.
Project description:We performed a transcriptome analysis of interior spruce (Picea glauca x engelmannii) bark response to weevil (Pissodes strobi) feeding using 21.8K spruce microarray (that contains 21.8 thousand unique transcripts). This microarray study revealed a large rearrangement of the interior spruce bark transcriptome in response to weevil feeding involving differential expression of close to 20% of the studied transcriptome. RNA was isolated from the bark of interior spruce exposed to weevil feeding and from the bark of untreated trees at three time points (6 hours, 2 days and 2 weeks). Four independent biological replicates were included for treatment and control at each time point. Four hybridizations were performed for treatment and control comparison within each time point (6 hours, 2 days, 2 weeks) and one hybridization was performed for each comparison between time points for both treatment and control (total 18 hybridizations/slides).
Project description:Using 21K spruce microarray (that contains 21.8 thousand unique transcripts) we performed analysis of the transcriptome response of interior spruce (Picea glauca x engelmannii) inoculated with the spruce beetle (Dendroctonus rufipennis) vectored blue stain fungal pathogen Leptographium abietinum or treated with wounding. This microarray analysis revealed large transcriptome reorganization with close to 2000 transcripts (10% of the studied transcriptome) differentially expressed within two weeks of treatment, with the wounding response affecting close to 5% of the interior spruce transcriptome.