Nejvíce citovaný článek - PubMed ID 24333335
Sphingolipid levels crucially modulate lateral microdomain organization of plasma membrane in living yeast
One of the best characterized fungal membrane microdomains is the MCC/eisosome. The MCC (membrane compartment of Can1) is an evolutionarily conserved ergosterol-rich plasma membrane domain. It is stabilized on its cytosolic face by the eisosome, a hemitubular protein complex composed of Bin/Amphiphysin/Rvs (BAR) domain-containing Pil1 and Lsp1. These two proteins bind directly to phosphatidylinositol 4,5-bisphosphate and promote the typical furrow-like shape of the microdomain, with highly curved edges and bottom. While some proteins display stable localization in the MCC/eisosome, others enter or leave it under particular conditions, such as misbalance in membrane lipid composition, changes in membrane tension, or availability of specific nutrients. These findings reveal that the MCC/eisosome, a plasma membrane microdomain with distinct morphology and lipid composition, acts as a multifaceted regulator of various cellular processes including metabolic pathways, cellular morphogenesis, signalling cascades, and mRNA decay. In this minireview, we focus on the MCC/eisosome's proposed role in the regulation of lipid metabolism. While the molecular mechanisms of the MCC/eisosome function are not completely understood, the idea of intracellular processes being regulated at the plasma membrane, the foremost barrier exposed to environmental challenges, is truly exciting.
- Klíčová slova
- MCC, eisosome, ergosterol, lipids, microdomain, phosphoinositides, regulation, sphingolipids,
- MeSH
- buněčná membrána metabolismus MeSH
- fosfatidylinositol-4,5-difosfát metabolismus MeSH
- fungální proteiny chemie metabolismus MeSH
- homeostáza MeSH
- houby metabolismus MeSH
- metabolismus lipidů MeSH
- proteinové domény MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- fosfatidylinositol-4,5-difosfát MeSH
- fungální proteiny MeSH
Phosducin (Pdc), a highly conserved phosphoprotein involved in the regulation of retinal phototransduction cascade, transcriptional control, and modulation of blood pressure, is controlled in a phosphorylation-dependent manner, including the binding to the 14-3-3 protein. However, the molecular mechanism of this regulation is largely unknown. Here, the solution structure of Pdc and its interaction with the 14-3-3 protein were investigated using small angle x-ray scattering, time-resolved fluorescence spectroscopy, and hydrogen-deuterium exchange coupled to mass spectrometry. The 14-3-3 protein dimer interacts with Pdc using surfaces both inside and outside its central channel. The N-terminal domain of Pdc, where both phosphorylation sites and the 14-3-3-binding motifs are located, is an intrinsically disordered protein that reduces its flexibility in several regions without undergoing dramatic disorder-to-order transition upon binding to 14-3-3. Our data also indicate that the C-terminal domain of Pdc interacts with the outside surface of the 14-3-3 dimer through the region involved in Gtβγ binding. In conclusion, we show that the 14-3-3 protein interacts with and sterically occludes both the N- and C-terminal Gtβγ binding interfaces of phosphorylated Pdc, thus providing a mechanistic explanation for the 14-3-3-dependent inhibition of Pdc function.
- Klíčová slova
- 14-3-3 protein, fluorescence, hydrogen-deuterium exchange, phosducin, protein complex, protein phosphorylation, small-angle x-ray scattering (SAXS),
- MeSH
- fosfoproteiny chemie genetika metabolismus MeSH
- fosforylace MeSH
- krysa rodu Rattus MeSH
- lidé MeSH
- molekulární modely MeSH
- oční proteiny chemie genetika metabolismus MeSH
- proteiny 14-3-3 chemie genetika metabolismus MeSH
- proteiny vázající GTP - regulátory chemie genetika metabolismus MeSH
- sekvence aminokyselin MeSH
- terciární struktura proteinů MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fosfoproteiny MeSH
- oční proteiny MeSH
- phosducin MeSH Prohlížeč
- proteiny 14-3-3 MeSH
- proteiny vázající GTP - regulátory MeSH
- YWHAZ protein, human MeSH Prohlížeč