IQUIBICEN   23947
INSTITUTO DE QUIMICA BIOLOGICA DE LA FACULTAD DE CIENCIAS EXACTAS Y NATURALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Promoter of Tpk1 catalytic subunit of PKA from S.cerevisiae: chromatin remodeling during heat shock
Autor/es:
RECA S; ROSSI S
Lugar:
Mar del Plata
Reunión:
Congreso; LI Reunion SAIB; 2015
Institución organizadora:
SAIB
Resumen:
Chromatin remodeling at gene promoters plays a critical role in initiation of transcription. This process is performed by a large class of ATP-dependent chromatin remodeling complexes as SWI/SNF, ISWI, CHD and INO80. Some have been suggested to play redundant roles and/or functionally interact with each other. During heat shock stress, the promoter of PKA catalytic subunit, TPK1 from S.cerevisiae is upregulated, chromatin remodeled and the two well positioned nucleosomes are evicted. In order to understand the mechanism by which the promoter is activated and the nucleosomes remodeled, the involvement of different remodelers was studied as a first approach using â-galactosidase reporter assay in null strains for each remodeler. The results indicate that SWI/SNF, and INO80 null strains lose the heat shock response. The remodeling of nucleosomes was further studied by MNase protection assay. The results show that a strain lacking the SWI/SNF activity, loses its ability to remove nucleosomes from TPK1 promoter during heat shock. Thus our results indicate that SWI/SNF and INO80 family are involved in remodeling of nucleosomes on TPK1 promoter in response to heat shock. Finally a strain with a deficient PKA activity (tpk1w-1) in which TPK1 promoter is fully activated the nucleosomes are also evicted even in the absence of heat shock .