Project description:This logical network model integrate signalling, transcriptional and epigenetic regulatory mechanisms underlying the the Acute Promyelocytic Leukaemia cell responses to RA treatment depending on their genetic background. The explicit inclusion of the histone methyltransferase EZH2 allowed us to assess its role in the maintenance of the resistant phenotype, distinguishing between its canonical and non-canonical activities. Ultimately, this model offers a solid basis to assess the roles of novel regulatory mechanisms, as well as to explore novel therapeutical approaches in silico.
Project description:The acetylation levels of histones and other proteins change during aging and have been linked to neurodegeneration. Here we show that deletion of the histone acetyltransferase (HAT) co-factor Trrap specifically impairs the function of the transcription factor Sp1, reduces its stability and causes a decrease in histone acetylation at Sp1 target genes. Modulation of Sp1 function by Trrap acts as a hub regulating multiple processes involved in neuron and neural stem cells function and maintenance including microtubule dynamics and the Wnt signaling pathway. Consistently, Trrap conditional mutants exhibit all hallmarks of neurodegeneration including dendrite retraction and axonal swellings, neuron death, astrogliosis, microglia activation, demyelination and decreased adult neurogenesis. Our results uncovered a novel functional network, essential to prevent neurodegeneration, and involving the specific regulation of Sp1 transcription factor and its downstream targets by Trrap-HAT.
