Cargando…
Transcriptional co-activator regulates melanocyte differentiation and oncogenesis by integrating cAMP and MAPK/ERK pathways
The cyclic AMP pathway promotes melanocyte differentiation by activating CREB and the cAMP-regulated transcription co-activators 1–3 (CRTC1–3). Differentiation is dysregulated in melanomas, although the contributions of CRTC proteins is unclear. We report a selective differentiation impairment in CR...
Autores principales: | , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
2021
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9678241/ https://www.ncbi.nlm.nih.gov/pubmed/34010639 http://dx.doi.org/10.1016/j.celrep.2021.109136 |
Sumario: | The cyclic AMP pathway promotes melanocyte differentiation by activating CREB and the cAMP-regulated transcription co-activators 1–3 (CRTC1–3). Differentiation is dysregulated in melanomas, although the contributions of CRTC proteins is unclear. We report a selective differentiation impairment in CRTC3 KO melanocytes and melanoma cells, due to downregulation of oculo-cutaneous albinism II (OCA2) and block of melanosome maturation. CRTC3 stimulates OCA2 expression by binding to CREB on a conserved enhancer, a regulatory site for pigmentation and melanoma risk. CRTC3 is uniquely activated by ERK1/2-mediated phosphorylation at Ser391 and by low levels of cAMP. Phosphorylation at Ser391 is constitutively elevated in human melanoma cells with hyperactivated ERK1/2 signaling; knockout of CRTC3 in this setting impairs anchorage-independent growth, migration, and invasiveness, whereas CRTC3 overexpression supports cell survival in response to the mitogen-activated protein kinase (MAPK) inhibitor vemurafenib. As melanomas expressing gain-of-function mutations in CRTC3 are associated with reduced survival, our results suggest that CRTC3 inhibition may provide therapeutic benefit in this setting. |
---|