Project description:We compare levels of gene expression in predator (Tigrosa helluo) exposed female Pardosa milvina compared to unexposed spiders and the offspring of predator exposed spiders to the offspring of control spiders.
Project description:Spiders are renowned for their efficient capture of flying insects using intricate aerial webs. How the spider nervous systems evolved to cope with this specialized hunting strategy and various environmental clues in an aerial space remains unknown. Here, we report a brain cell atlas of >30,000 single-cell transcriptomes from a web-building spider (Hylyphantes graminicola). Our analysis revealed the preservation of ancestral neuron types in spiders, including the potential coexistence of noradrenergic and octopaminergic neurons, and many peptidergic neuronal types that are lost in insects. By comparing the genome of two newly sequenced plesiomorphic burrowing spiders with three aerial web-building spiders, we found that the positively selected genes in the ancestral branch of web-building spiders were preferentially expressed (42%) in the brain, especially in the three mushroom body-like neuronal types. By gene enrichment analysis and RNAi experiments, these genes were suggested to be involved in the learning and memory pathway and may influence the spiders’ web-building and hunting behavior. Our results provide key sources for understanding the evolution of behavior in spiders and reveal how molecular evolution drives neuron innovation and the diversification of associated complex behaviors.
Project description:The “ship of the desert”, the one-humped Arabian camel (Camelus dromedarius), has a remarkable capacity to survive in conditions of extreme heat without needing to drink water. One of the ways that this is achieved is through the actions of the antidiuretic hormone vasopressin (AVP) and the natriuretic hormone oxytocin (OXT), both of which are made in a specialised part of the brain called the hypothalamo-neurohypophyseal system (HNS), but exert their effects at the level of the kidney to, respectively, provoke water conservation and salt excretion. Interestingly, our electron microscopy studies have shown that the ultrastructure of the camel HNS changes according to season, suggesting that in the arid conditions of summer the dromedary’s HNS is in a state of permanent activation, in preparation for the likely prospect of water deprivation. Based on our camel genome sequence, we have carried out an RNAseq analysis of the camel HNS in summer and winter.
Project description:To investigate the central control of water homeostasis in the dromedary camel, we have performed transcriptomic studies on the supraoptic nucleus samples from camels under control (water ad libitum) and dehydrated (water deprivation for 20 days) conditions by RNA sequencing. We have identified genes that change in expression in response to hyperosmotic challenge and transcriptomic response networks that might be essential for adaptations of camel to live and thrive in aird desert environment.
Project description:The utility of RADseq in an experimental setting is also demonstrated, based on our chasacterisation of an APOBEC mutation signature in an APOBEC3A transfected mouse cell line. 0D5 cells, derived from SSM3 cells, were co-transfected with a mixture containing pcDNA3.1 vectors expressing either APOBEC3A or APOBEC3B (kindly donated by Vincent Caval), pcDNA3.1 construct expressing deaminase null APOBEC3A linked to a uracil deglycosylase construct and a plasmid encoding mutant GFP and WT mCherry that is a reporter for APOBEC mutagenesis. Cells were grown, and gDNA extracted, prior to preparation of RADseq libraries using a PstI- MspI double-digest. Libraries underwent a Pippin Prep to select fragments in the size range of 220-520 bp (genomic sequence plus 148 bp of adapters). Single-end sequencing (1x101bp) was performed on an Illumina NovaSeq6000 utilizing v1.5 chemistry. Reads were aligned to mm10 using bwa mem and variants called using the GATK4 pipeline.
Project description:Proteins extracted from camel urine by ultrafiltration and precipitation were fractionated by SDS-PAGE, digested in-gel, then analysed by LC-MS/MS with camel EST sequence database search