Roland Abi Nahed

Abstract Acetyl and other acyl groups from different short-chain fatty acids (SCFA) competitively modify histones at various lysine sites. To fully understand the functional significance of such histone acylation, a key epigenetic mechanism, it is crucial to characterize the cellular sources of the corresponding acyl-CoA molecules required for the lysine modification.

1. Introduction 1.1. Background Cellular prion protein (PrPC) is a glycosylphosphatidylinositol (GPI)-anchored glycoprotein expressed on the cell surface in various organs and tissues [1]. The PrPC protein is encoded by the PRNP gene that is localized on Chromosome 20 and 2 in humans and in mice, respectively [1]. PrPC is first synthesized as a pre-pro-protein with a leader peptide at the N-terminal tail, and a GPI anchor signaling peptide (GPI-PSS) at the C-terminal tail.

Abstract AMP-activated protein kinase (AMPK) has evolved to detect a critical increase in cellular AMP/ATP and ADP/ATP concentration ratios as a signal for limiting energy supply. Such energy stress then leads to AMPK activation and downstream events that maintain cellular energy homeostasis. AMPK activation by AMP, ADP or pharmacological activators involves a conformational switch within the AMPK heterotrimeric complex.