show Abstracthide AbstractThe dynamic transcriptional regulation and interactions of human germlines and surrounding somatic cells during folliculogenesis remains unknown. Using RNA-Seq analysis of human oocytes and corresponding granulosa cells (GCs) spanning five follicular stages, we revealed unique features in transcriptional machinery, transcription factor networks and reciprocal interactions in human oocytes and GCs that displayed developmental-stage-specific expression patterns. Notably, we identified specific gene signatures of two cell types in particular developmental stage that may reflect developmental competency and ovarian reserve. Additionally, we uncovered key pathways that may concert germline-somatic interactions and drive the transition of primordial-to-primary follicle which represents follicle activation. Thus, our work provides key insights into the crucial features of the transcriptional regulation in the stepwise folliculogenesis and offers important clues for improving follicle recruitment in-vivo and restoring fully competent oocytes in-vitro. Overall design: Transcriptome profiles of oocytes and granulosa cells from five follicle development stages were generated by deep sequencing using illumina Hiseq X10.