Spatial single-cell sequencing of meiosis I arrested oocytes indicates acquisition of maternal transcripts from the soma

Maternal RNAs are stored from minutes to decades in oocytes throughout meiotic arrest. The nature and dynamics of maternal RNAs during this arrest remain uncharted. We address this by performing single-oocyte RNA sequencing on arrested and maturing C. elegans oocytes. We discovered a population of transcripts that increases as the arrested meiosis I oocyte ages, but ruled out ERK signaling and nascent transcription as a mechanism for this increase. Instead, we report extracellular communication from neighboring somatic cells as a mechanism for the increase in transcripts during meiosis I arrest. These analyses provide a single-cell resolution of the RNA landscape during the developmental history of a meiosis I arrested oocyte and as it prepares for oocyte maturation and embryonic progression. Overall design: Comparative gene profiling analysis of RNA seq data from different ages of oocytes in the Caenorhabditis germline