INPROTEOLYS

Marc Piechaczyk

Research interest:

 One of the major topics addressed in our laboratory is the regulation and function of the AP-1 transcription complex during the cell cycle and in immune cells. AP-1 is, in fact, a family of dimeric transcription factors, the best known components of which are the members of the Fos and Jun multigene families. It controls most vital cell functions and its dysfunction has various pathological consequences including cancerogenesis. However, depending on the context, certain AP-1 proteins can manifest either oncogenic or anti-oncogenic properties on their own or be necessary mediators of other oncogenes activated upstream. In our lab, we are studying how post-translational modifications control AP-1 protein abundance and activity. Among our most recent observations, one can cite: (i) the demonstration of a proteasome-dependent, but ubiquitin-independent, degradation of two Fos proteins, c-Fos and Fra-1, (ii) the transcriptional repression of c-Fos by sumoylation, the latter being itself subjected to a complex regulation via diverse signaling pathways, including those involving reactive oxygen species, (iii) a particular intracellular and intranuclear dynamics of Fos and Jun proteins and (iv) the requirement of JunB protein in late G2 for proper progression through subsequent mitosis. Our investigations are conducted in physiological systems, such as dividing cells of various sorts and during maturation of dendritic cells by pathogens, and in pathological situations, including different cancers where intracellular signaling is altered. They aim at better understanding the molecular basis of tumorigenesis and of the immune response.

E-mail		marc.piechaczyk@igmm.cnrs.fr

Phone		33 (0)4 67 61 36 68

Address		IGMM - CNRS - 1919, route de Mende - 34293 - Montpellier Cedex 05

Personal Web		http://www.igmm.cnrs.fr/spip.php?rubrique37

Curriculum Vitae		Marc Piechaczyk CV

Keywords		Oncogenesis, transcription factors, Fos, Jun, protein degradation, sumoylation, gene regulation, cell signallng, retrovirology, immune response, dendritic cells