Gene Expression analysis of transgenic RAS heatshock zebrafish embryos at 30 hpf

Heterogeneous Tg(hsp70-hRASG12V) embryos were obtained by mating the male homozygous transgenic fish to wildtype females. They were raised to 24 hour-post fertilization (hpf) stage and received heatshock at 37°C in waterbath for one hour, and kept in 28.5°C till 30hpf for RNA extraction. Wildtype embryos receiving the same heatshock treatment were used as controls. Each microarray sample was prepared by pooling 50 embryos and biological duplication was used. The zebrafish has been established as a powerful vertebrate model organism for large-scale genetic screens and chemical screens. Here, we seek to establish that zebrafish embryos can be utilized as an in vivo system to dissect crucial pathways for oncogenesis. A microarray analysis was performed by comparing transcription profile of heterogeneous Tg(hsp70-hRASG12V) embryos with heatshock to wildtype embryos with heatshock. Both groups of embryos received heatshock at 37°C for one hour at 24 hour-post fertilization (hpf) stage, and kept in 28.5°C till 30hpf for RNA extraction. Each microarray sample was prepared by pooling 50 embryos and biological triplicate was used. Ingenuity Pathway Analysis (IPA) was performed using the upregulated lists. “Cancer “ was the top diseases and disorders, with “Developmental disorder” and “Organismal Injury and Abnormalities” as the second and third diseases and disorders, validating that transient heatshock induction of oncogenic RAS in embryos activates major pathways in oncogenesis.