Induction of HoxB transcription by retinoic acid requires actin polymerization.

GABRIELA NAUM ONGANIA*; CARMELO FERRAI*; ELENA LONGOBARDI; MARTINA PALAZZOLO; ANDREA DISANZA; VICTOR M. DIAZ; MASSIMO CRIPPA; GIORGIO SCITA; FRANCESCO BLASI

MOLECULAR BIOLOGY OF THE CELL

AMER SOC CELL BIOLOGY

Año: 2009 vol. 15 p. 3543 - 3551

1059-1524

ESTE ARTICULO FUE CITADO POR EL PREMIO NOBEL DE FISIOLOGIA Y MEDICINA 2012,  JOHN GURDON  en su articulo publicado en  Genes & Development: "Nuclear actin polymerization is required for transcriptional reprogramming of Oct4 by oocytes" K. Myamoto, V. Pasque, Julien J and Gurdon JB.ABSTRACT. We have analyzed the role of actin polymerization in the retinoic acid (RA) induction of HoxB transcription, which is mediated by the HoxB regulator Prep1. Three different approaches to inhibit actin polymerization prevent RA induction of the HoxB genes. Importantly, inhibition of actin polymerization affects specifically the transcription of inducible Hox genes, but not that their transcriptional regulators RA receptors, nor of constitutive or of already activated Hox genes. The effect depends on the inhibition of the RA-dependent recruitment to the enhancer of the HoxB2 gene of a complex composed by elongating RNA Pol II, Prep1, B-actin, N-WASP as well as the accessory splicing components p54(nrb) and PSF.We conclude that inducible Hox genes show a selective sensitivity to the block of actin polymerization and that actin polymerization is required to assemble a transcription complex onto the regulatory region of the Hox genes. NOTA: *this two authors share the first authorship.