RT Journal Article
SR Electronic
T1 Acute perturbation of retromer and ESCPE-1 leads to functionally distinct and temporally resolved defects in endosomal cargo sorting
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 836460
DO 10.1101/836460
A1 Ashley J. Evans
A1 James L. Daly
A1 Anis N. K. Anuar
A1 Boris Simonetti
A1 Peter J. Cullen
YR 2019
UL http://biorxiv.org/content/early/2019/11/12/836460.abstract
AB The human retromer is a stable heterotrimer of VPS35, VPS29 and VPS26 whose principal role is to orchestrate the endosomal retrieval of hundreds of internalised cargo and promote their recycling to the cell surface; a prototypical cargo being the glucose transporter GLUT1. Retromer’s role in a distinct endosomal retrieval pathway, the retrograde sorting of the cation-independent mannose 6-phosphate receptor (CI-MPR) to the trans-Golgi network (TGN), remains controversial. Here we have developed and applied knocksideways to acutely inactivate retromer and by visualising the sorting of endogenous GLUT1 and CI-MPR provide insight into the temporal dynamics of endosomal cargo sorting in HeLa and H4 human neuroglioma cells. While retromer knocksideways led to the development of time-resolved defects in cell surface sorting of GLUT1 we failed to observe defects in the sorting of the CI-MPR. In contrast knocksideways of ESCPE-1, a key regulator of retrograde CI-MPR sorting, resulted in a time-resolved defect in CI-MPR sorting. Together these data provide independent evidence consistent with a comparatively limited role for retromer in ESCPE-1 dependent CI-MPR retrograde sorting in HeLa and H4 human neuroglioma cells.