Transcriptomic analyses identify pathways linking developmental atrazine exposure to altered intestine development
Purpose: Identify gene expression changes in whole intestines of Xenopus laevis embryos exposed to atrazine (35 mg/L) compared to DMSO controls Methods: NF 39 embryos were exposed to 35 mg/L ATR or DMSO control for 24 hours. After 24 hours of exposure, intestines from embryos of each treatment group were dissected from anesthetized embryos with sharpened forceps. The anterior portion of the embryo (including the head, heart, and foregut) were removed and discarded, leaving only the mid-and hindgut portion of the intestine. Intestines from multiple embryos were removed, combined within a microcentrifuge tube containing TRIzol™ Reagent (Invitrogen) such that each replicate contained 10 intestines (n = 4). RNA extraction was performed using the TRIzol™ Reagent (Invitrogen) according to the manufacturer's instructions, followed by lithium chloride precipitation. Quality and quantity of RNA yield was confirmed on a Thermo Fisher Scientific Nanodrop 1000 and an Agilent 2100 Bioanalyzer. RNA-seq was performed by North Carolina State University's Genomic Sciences Laboratory with an Illumina poly-A enriched directional RNA library and an Illumina NovaSeq 6000 was used for sequencing (SP 150 bp PE flow cell). Results: We identified 254 significantly differentially expressed genes (p-adj<0.05) between DMSO and atrazine exposed intestines Conclusions: Gene Ontology analysis of the differentially expressed genes revealed an enrichment for pathways involved in cellular stress, EMT, and the cell cycle, along with pathways involved in cellular (glucose)metabolism. Overall design: atrazine-exposed mRNA profiles from whole intestines of DMSO control (n=4) and 35 mg/L atrazine-exposed (n=4) Xenopus laevis embryos after 24 hours.