Selective YAP1 Transcriptional Response to Graded Retinoic Acid Exposure in NTERA-2 Cells

Background: Retinoic acid (RA) regulates neural cell-state transitions, but its effects on Hippo-pathway effectors in NTERA-2 cells remain incompletely defined. Methods: NTERA-2 cultures were exposed for seven days to 5, 10, or 15 µM RA, with untreated and 0.1% DMSO controls (n = 3 parallel flasks per group from the same passage and starting suspension). YAP1, WWTR1, NPTN, and miR-148a-3p expressions were quantified by RT-qPCR. RA-versus-DMSO comparisons were evaluated on the −ΔCq scale with false-discovery-rate correction and sensitivity analyses. Results: Metabolic viability remained at 95–97% of untreated-control values. Relative to DMSO, YAP1 expression was 9.73-fold and 8.14-fold higher at 5 and 10 µM RA, respectively (q = 0.0462 for both), although levels remained below untreated control and direct RA-versus-untreated comparisons were nonsignificant. No corrected differences were detected for WWTR1 or NPTN. miR-148a-3p comparisons were nonsignificant and interpreted cautiously because miR-26b-5p showed condition-dependent variation. Conclusions: Seven-day RA exposure was associated with a selective YAP1 transcriptional response relative to the DMSO background at 5–10 µM. The pattern is also compatible with partial attenuation of a vehicle-associated reduction rather than induction above baseline. These transcript-level data do not establish neuronal maturation or Hippo-pathway activation.