Phosphorylation of BRN2 modulates its interaction with the Pax3 promoter to control melanocyte migration and proliferation

Autor: Laurence Denat, Colin R. Goding, Irwin Davidson, Delphine Champeval, Anne-Lise Steunou, Véronique Delmas, Laurence Nieto, Irina Berlin, Isabel Puig, Yveline Bourgeois, Elise Bonvin, Karen Roberts, Lionel Larue, Sophie Colombo
Jazyk: angličtina
Rok vydání: 2012
Předmět:
Zdroj: Molecular and cellular biology. 32(7)
ISSN: 1098-5549
0270-7306
Popis: MITF-M and PAX3 are proteins central to the establishment and transformation of the melanocyte lineage. They control various cellular mechanisms, including migration and proliferation. BRN2 is a POU domain transcription factor expressed in melanoma cell lines and is involved in proliferation and invasion, at least in part by regulating the expression of MITF-M and PAX3. The T361 and S362 residues of BRN2, both in the POU domain, are conserved throughout the POU protein family and are targets for phosphorylation, but their roles in vivo remain unknown. To examine the role of this phosphorylation, we generated mutant BRN2 in which these two residues were replaced with alanines (BRN2TS→BRN2AA). When expressed in melanocytes in vitro or in the melanocyte lineage in transgenic mice, BRN2TS induced proliferation and repressed migration, whereas BRN2AA repressed both proliferation and migration. BRN2TS and BRN2AA bound and repressed the MITF-M promoter, whereas PAX3 transcription was induced by BRN2TS but repressed by BRN2AA. Expression of the BRN2AA transgene in a Mitf heterozygous background and in a Pax3 mutant background enhanced the coat color phenotype. Our findings show that melanocyte migration and proliferation are controlled both through the regulation of PAX3 by nonphosphorylated BRN2 and through the regulation of MITF-M by the overall BRN2 level.
Databáze: OpenAIRE