Mitochondria are key organelles in the cell, hosting essential functions, from biosynthetic and metabolic pathways, to oxidative phosphorylation and ATP production, from calcium buffering to red-ox homeostasis and apoptotic signalling pathways. signals of death. In regard to the cell GW2580 enzyme inhibitor life, mitochondria produce most of the ATP necessary to the cell through oxidative phosphorylation, and they are involved, among the others, in TCA cycle, fatty acid metabolism, hemesynthesis, and gluconeogenesis. As regards the cell death, mitochondria are involved in Ca2+ and red-ox homeostasis, which are dysregulated during cell death, and they release proapoptotic proteins, such as cytochrome genetic ablation of fusion (knock-out GW2580 enzyme inhibitor mice [29, 30], double knock-out mice ), or fission (knock-out mice ) proteins results in early embryonic lethality. Other data reveal mutations or abnormal regulation of mitochondria shaping proteins in many pathological conditions, as we will see below. 2. Cancer According to the classification of the hallmarks of cancer by Hanahan and Weinberg , a cell needs a multistep process to become tumoral and, later on, to develop metastasis. Mitochondria are crucially positioned for establishing resistance to cell death and sustaining proliferative signallings. Their role is essential for the metabolic shift to glycolysis (the so-called Warburg effect), common in tumoral cells. Increasing evidence shows the involvement of mitochondrial dynamics in cancer GW2580 enzyme inhibitor development (see Table 1). Table 1 Mitochondrial dynamics and cancer. amiloyd accumulation and interaction with DRP1, enhanced CDK1 activity, altered interaction between mitochondria and Kinesin motor complex in cerebral cortex GW2580 enzyme inhibitor [77C79]. . That said, increasing data are emerging in experimental models. Anterograde and retrograde trafficking is altered in Amyotrophic lateral sclerosis (ALS) mouse models in which SOD1 [65, 66], guanin-nucleotide exchange factor (GEF) and TAR DNA-binding protein 43 (TDP-43) are mutated [67, 68]. Noteworthy, a role for mitochondrial trafficking impairment has been demonstrated in pathologies not only affecting long axon neurons but also short cortex and hippocampal ones (this is the case of Alzheimer diseaseADmodels) GW2580 enzyme inhibitor [64, 69, 70]. Similar observations come from works in a Huntington’s disease (HD) mouse model, in which mutated (the gene of HUNTINGTIN protein) is able to block mitochondrial movement  and causes a redistribution of kinesin and dynein in primary cortical neurons ; in Parkinson disease (PD) cellular and mouse models where PINK1 has been shown to interact with MIRO and MILTON , as well as with induces stabilization of PINK1 on the OMM and allows PARKIN recruitment on mitochondria. This, in turn, leads to ubiquitination of mitochondrial substrates and their interaction with p62 and LC3 so as to induce the engulfment of mitochondria inside the autophagosome [24, 25]. MFNs, for example, are ubiquitinated in a PARKIN-dependent manner  and then degraded by proteasome . Others showed that DRP1 stability is also regulated by PARKIN . 3.2. Focus on the Pathologies Coming back to the pathologies, in this paragraph, we will focus on the links between some of them and the mitochondrial dynamics. 3.2.1. Alzheimer Disease The main clinical feature of Alzheimer disease (AD) is the accumulation of extracellular deposits of amyloid (Ainteracts with DRP1 , promoting mitochondrial fission in a DRP1 S-nitrosilation-dependent manner [110, 111]. Tissues from patients affected by AD show mitochondria with disrupted cristae structure  and reduction of the number of mitochondria in dendrites . Interestingly, although cell-cycle-coupled events are rare in postmitotic cells, the activity of CDK1 and CDK5 is enhanced in AD. CDK5 phosphorylates tau , while a high level of phosphorylated DRP1 at Serine 616 appears to be dependent on both CDK1 and protein kinase GATA3 C (PKC models of HD. In addition, 3-nitropropionic acid, an irreversible inhibitor of complex II, has been shown to induce mitochondrial fragmentation and HD-like symptoms in rats and mice . Of note is that primary striatal neurons from HD mouse models reveal mitochondrial fragmentation  with an alteration of mitochondrial shaping proteins in the brain (DRP1 and FIS1 upregulation, OPA1 and MFN1 downregulation) . Mutant HUNTINGTIN is.