RT Journal Article
SR Electronic
T1 Diffusion and interaction dynamics of the cytosolic peroxisomal import receptor PEX5
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.05.25.445571
DO 10.1101/2021.05.25.445571
A1 S Galiani
A1 K Reglinski
A1 P Carravilla
A1 A Barbotin
A1 I Urbančič
A1 J Ott
A1 J Sehr
A1 E Sezgin
A1 F Schneider
A1 D Waithe
A1 P Hublitz
A1 W Schliebs
A1 R Erdmann
A1 C Eggeling
YR 2021
UL http://biorxiv.org/content/early/2021/05/26/2021.05.25.445571.abstract
AB Measuring diffusion dynamics in living cells is essential for the understanding of molecular interactions. While various techniques have been used to explore such characteristics in the plasma membrane, this is less developed for measurements inside the cytosol. An example of cytosolic action is the import of proteins into peroxisomes, via the peroxisomal import receptor PEX5. Here, we combined advanced microscopy and spectroscopy techniques such as fluorescence correlation spectroscopy (FCS) and super-resolution STED microscopy to present a detailed characterization of the diffusion and interaction dynamics of PEX5. Among other features, we disclose a slow diffusion of PEX5, independent of aggregation or target binding, but associated with cytosolic interaction partners via its N-terminal domain. This sheds new light on the functionality of the receptor in the cytosol. Besides specific insights, our study highlights the potential of using complementary microscopy tools to decipher molecular interactions in the cytosol via studying their diffusion dynamics.Summary The peroxisomal import receptor PEX5 transports newly synthesized proteins from the cytosol to the peroxisomal matrix. Here the cytosolic diffusion and interaction dynamics of PEX5 are characterized by advanced microscopic spectroscopy methods, revealing a so far unknown interaction partner.Competing Interest StatementThe authors have declared no competing interest.ACFautocorrelation functionAOAdaptive OpticsCRISPRClustered Regularly Interspaced Short Palindromic RepeatsFCSFluorescence Correlation SpectroscopyGPMVGiant Plasma Membrane VesiclePEXperoxinPTS1peroxisomal targeting signal type 1SiRoSilicon RhodamineSTEDstimulated emission depletion