Minor expression of fascin-1 gene (FSCN1) in NTera2 cells depleted of CREB-binding protein.

CREB-binding protein (CBP) is a transcriptional coactivator whose mutations may cause a generalized perturbation of gene expression. We silenced the CBP gene in NT2 neuronal precursor cells by RNA interference. Hybridization experiments on 1.2K human cDNA microarrays showed that the FSCN1 gene, encoding for fascin-1 protein, was clearly less expressed in CBP-depleted cells than in controls. This reduction was confirmed by Real Time PCR and Western blotting assays. We also analyzed FSCN1 expression profile during NT2 neuronal differentiation induced by retinoic acid (RA), showing that FSCN1 was up-regulated during neurogenesis. This mRNA increasing suggests the importance of fascin-1 in the formation of mature neurons, in accordance with its actin-bundling function and its localization in neurites and neuronal growth cones. The lower amount of FSCN1 transcript in the absence of the CBP factor was also established in RA-treated cells. In conclusion, this research supports FSCN1 as a novel marker of NT2 neuronal differentiation and the possible role of CBP in its regulation.