Developmental Circadian Disruption Alters Placental Signaling in Mice

We investigated the impacts of environmental circadian disruption on placental gene expression (E15.5) in a C57BL/6J mouse (Mus musculus) model. A number of transcripts showed sex-specific patterns of expression and several transcripts were differentially expressed in placenta from mice developmentally exposed to circadian disruption compared to mice exposed to control light. Female C57BL/6J mice were randomized into 2 different light treatments: standard control lighting (CL, 12:12 light:dark) schedule, or circadian disruption (inversions of the photoperiod every 3-4 days)). Females remained in this light treatment for 4 weeks of pre-dosing before timed breeding with male mice. Females remained in their light treatments until placental tissue collection at E15.5. Samples were collected from 6 pregnant mice in the CL group and 6 pregnant mice in the CD group. 2 placenta from each dam were selected for representation of a male and female sample (where possible) from each dam, for a total of 24 placenta samples. Isolated RNA were sequenced with PolyA RNA sequencing (paired-end) at a 30M read depth.