RNAi Reveals Phase-Specific Global Regulators of Human Somatic Cell Reprogramming

Incomplete knowledge of the mechanisms at work continues to hamper efforts to maximize reprogramming efficiency. Here, we present a systematic genome-wide RNAi screen to determine the global regulators during the early stages of human reprogramming. Our screen identifies functional repressors and effectors that act to impede or promote the reprogramming process. Repressors and effectors form close interacting networks in pathways, including RNA processing, G protein signaling, protein ubiquitination, and chromatin modification. Combinatorial knockdown of five repressors (SMAD3, ZMYM2, SFRS11, SAE1, and ESET) synergistically resulted in ∼85% TRA-1-60-positive cells. Removal of the novel splicing factor SFRS11 during reprogramming is accompanied by rapid acquisition of pluripotency-specific spliced forms. Mechanistically, SFRS11 regulates exon skipping and mutually exclusive splicing of transcripts in genes involved in cell differentiation, mRNA splicing, and chromatin modification. Our study provides insights into the reprogramming process, which comprises comprehensive and multi-layered transcriptional, splicing, and epigenetic machineries.
Singapore. Agency for Science, Technology and Research (grant JCO R09138)
Singapore. Agency for Science, Technology and Research (grant JCO R09125)
Singapore. Agency for Science, Technology and Research (Investigatorship research award)
National Institutes of Health (U.S.) (NIH grant CA196631-01A1)
National Institutes of Health (U.S.) (NIH grant 1U54GM114838-01)