title: Participation of transcription factors from the Rel/NF-kappa B family in the circadian system in hamsters.
abstract: We have studied the presence and activity of components of the nuclear factor-kappaB (NF-kappaB) transcription factor in the hamster circadian system analyzing wheel-running activity, protein expression and DNA binding activity by electrophoresis mobility shift assays (EMSA). Non-rhythmic specific immunoreactive bands corresponding to a NF-kappaB subunit (p65) were found in hamster suprachiasmatic nuclei (SCN) homogenates. The active form of NF-kappaB evidenced by EMSA was clear and specific in SCN nuclear extracts. The administration of the NF-kappaB inhibitor pyrrolidine-dithiocharbamate (PDTC) blocked the light-induced phase advance at circadian time 18 (vehicle+light pulse: 2.08+/-0.46 h, PDTC+light: 0.36+/-0.35 h). These results demonstrate the presence and activity of Rel/NF-kappaB family proteins in the hamster SCN and suggest that these proteins may be related to the entrainment and regulation of circadian rhythms.
authors.affiliation: Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Roque Sáenz Peña 180, Bernal, B1876BXD Pcia. de Buenos Aires, Argentina.
authors.forename: Luciano
authors.initials: L
authors.lastname: Marpegan
authors.forename: Tristan A
authors.initials: TA
authors.lastname: Bekinschtein
authors.forename: Ramiro
authors.initials: R
authors.lastname: Freudenthal
authors.forename: M Fernanda
authors.initials: MF
authors.lastname: Rubio
authors.forename: Gabriela A
authors.initials: GA
authors.lastname: Ferreyra
authors.forename: A
authors.initials: A
authors.lastname: Romano
authors.forename: D A
authors.initials: DA
authors.lastname: Golombek
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D006224:Cricetinae; D008297:Male; D008647:Mesocricetus; D016328:NF-kappa B / Q000096:biosynthesis* / Q000235:genetics; D020572:Oncogene Proteins v-rel / Q000096:biosynthesis* / Q000235:genetics; D013493:Suprachiasmatic Nucleus / Q000378:metabolism*; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D016328:NF-kappa B; D020572:Oncogene Proteins v-rel; D014157:Transcription Factors