“…Indeed, every combination containing RA resulted in significantly higher TUBB3 expression compared to spontaneous differentiation. Identification of RA as a strong inducer of neuronal differentiation was not surprising, as RA is well known to induce neuronal differentiation on multiple types of neural progenitor cells (Erceg et al, 2008; Janesick, Wu, & Blumberg, 2015; Takahashi, Palmer, & Gage, 1999). It was interesting, however, that in our screen RA treatment alone was not identified as being statistically significant, but combined treatment of RA with other led to more pronounced effects, which is consistent with its differentiation inducing effects reported in the literature (Encinas et al, 2000; Takahashi et al, 1999).…”