The loss of mitochondria in oxymonad protists has been associated with the redirection of the essential Fe-S cluster assembly to the cytosol. Yet as our knowledge of diverse free-living protists broadens, the list of functions of their mitochondrial-related organelles (MROs) expands. We revealed another such function in the closest oxymonad relative, Paratrimastix pyriformis, after we solved the proteome of its MRO with high accuracy, using localization of organelle proteins by isotope tagging (LOPIT). The newly assigned enzymes connect to the glycine cleavage system (GCS) and produce folate derivatives with one-carbon units and formate. These are likely to be used by the cytosolic methionine cycle involved in S-adenosyl methionine recycling. The data provide consistency with the presence of the GCS in MROs of free-living species and its absence in most endobionts, which typically lose the methionine cycle and, in the case of oxymonads, the mitochondria.

• Klíčová slova
• LOPIT, Paratrimastix, glycine cleavage system, methionine cycle, mitochondrion-related organelle, one-carbon metabolism, proteome, spatial proteomics,
• MeSH
• Eukaryota metabolismus   MeSH
• methionin * MeSH
• mitochondrie * metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• methionin * MeSH

Tunnelling nanotubes (TNTs) are an emerging route of long-range intercellular communication that mediate cell-to-cell exchange of cargo and organelles and contribute to maintaining cellular homeostasis by balancing diverse cellular stresses. Besides their role in intercellular communication, TNTs are implicated in several ways in health and disease. Transfer of pathogenic molecules or structures via TNTs can promote the progression of neurodegenerative diseases, cancer malignancy, and the spread of viral infection. Additionally, TNTs contribute to acquiring resistance to cancer therapy, probably via their ability to rescue cells by ameliorating various pathological stresses, such as oxidative stress, reactive oxygen species (ROS), mitochondrial dysfunction, and apoptotic stress. Moreover, mesenchymal stem cells play a crucial role in the rejuvenation of targeted cells with mitochondrial heteroplasmy and oxidative stress by transferring healthy mitochondria through TNTs. Recent research has focussed on uncovering the key regulatory molecules involved in the biogenesis of TNTs. However further work will be required to provide detailed understanding of TNT regulation. In this review, we discuss possible associations with Rho GTPases linked to oxidative stress and apoptotic signals in biogenesis pathways of TNTs and summarize how intercellular trafficking of cargo and organelles, including mitochondria, via TNTs plays a crucial role in disease progression and also in rejuvenation/therapy.

• Klíčová slova
• Apoptosis, Cellular stress, Chemotherapy resistance, Intercellular transfer, Mesenchymal stem cells, Mitochondrial homeostasis, Reactive oxygen species (ROS), Rejuvenation,
• MeSH
• lidé MeSH
• mezibuněčná komunikace * MeSH
• mitochondrie metabolismus   MeSH
• nádory metabolismus   patologie   MeSH
• neurodegenerativní nemoci metabolismus   patologie   MeSH
• organely metabolismus   MeSH
• oxidační stres * MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• rho proteiny vázající GTP fyziologie   MeSH
• virové nemoci metabolismus   patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• reaktivní formy kyslíku MeSH
• rho proteiny vázající GTP MeSH

The distinctive pathological hallmarks of Parkinson's disease are the progressive death of dopaminergic neurons and the intracellular accumulation of Lewy bodies enriched in α-synuclein protein. Several lines of evidence from the study of sporadic, familial and pharmacologically induced forms of human Parkinson's disease also suggest that mitochondrial dysfunction plays an important role in disease progression. Although many functions have been proposed for α-synuclein, emerging data from human and animal models of Parkinson's disease highlight a role for α-synuclein in the control of neuronal mitochondrial dynamics. Here, we review the α-synuclein structural, biophysical and biochemical properties that influence relevant mitochondrial dynamic processes such as fusion-fission, transport and clearance. Drawing on current evidence, we propose that α-synuclein contributes to the mitochondrial defects that are associated with the pathology of this common and progressive neurodegenerative disease.

• Klíčová slova
• Fusion-fission, Mitochondria, Mitophagy, Parkinson's disease, Synuclein, Transport,
• MeSH
• alfa-synuklein chemie   metabolismus   MeSH
• biologické modely MeSH
• lidé MeSH
• mitochondriální dynamika * MeSH
• mitofagie MeSH
• Parkinsonova nemoc metabolismus   patologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• alfa-synuklein MeSH

Cell polarity, the asymmetric organization of cellular components along one or multiple axes, is present in most cells. From budding yeast cell polarization induced by pheromone signaling, oocyte polarization at fertilization to polarized epithelia and neuronal cells in multicellular organisms, similar mechanisms are used to determine cell polarity. Crucial role in this process is played by signaling lipid molecules, small Rho family GTPases and Par proteins. All these signaling circuits finally govern the cytoskeleton, which is responsible for oriented cell migration, cell shape changes, and polarized membrane and organelle trafficking. Thus, typically in the process of cell polarization, most cellular constituents become polarized, including plasma membrane lipid composition, ion concentrations, membrane receptors, and proteins in general, mRNA, vesicle trafficking, or intracellular organelles. This review gives a brief overview how these systems talk to each other both during initial symmetry breaking and within the signaling feedback loop mechanisms used to preserve the polarized state.

• Klíčová slova
• Cell polarization, Cell signaling, Chemotaxis, Neurite initiation, Par proteins, Rho GTPases,
• MeSH
• membránové proteiny metabolismus   MeSH
• mikrofilamenta metabolismus   MeSH
• mikrotubuly metabolismus   MeSH
• nádorové proteiny metabolismus   MeSH
• neutrofily metabolismus   MeSH
• pohyb buněk fyziologie   MeSH
• polarita buněk fyziologie   MeSH
• rho proteiny vázající GTP metabolismus   MeSH
• signální transdukce fyziologie   MeSH
• tvar buňky fyziologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• JTB protein, human MeSH Prohlížeč
• membránové proteiny MeSH
• nádorové proteiny MeSH
• rho proteiny vázající GTP MeSH