Diagenode

Aster Proteins Facilitate Nonvesicular Plasma Membrane to ER Cholesterol Transport in Mammalian Cells.


Sandhu J, Li S, Fairall L, Pfisterer SG, Gurnett JE, Xiao X, Weston TA, Vashi D, Ferrari A, Orozco JL, Hartman CL, Strugatsky D, Lee SD, He C, Hong C, Jiang H, Bentolila LA, Gatta AT, Levine TP, Ferng A, Lee R, Ford DA, Young SG, Ikonen E, Schwabe JWR, To

The mechanisms underlying sterol transport in mammalian cells are poorly understood. In particular, how cholesterol internalized from HDL is made available to the cell for storage or modification is unknown. Here, we describe three ER-resident proteins (Aster-A, -B, -C) that bind cholesterol and facilitate its removal from the plasma membrane. The crystal structure of the central domain of Aster-A broadly resembles the sterol-binding fold of mammalian StARD proteins, but sequence differences in the Aster pocket result in a distinct mode of ligand binding. The Aster N-terminal GRAM domain binds phosphatidylserine and mediates Aster recruitment to plasma membrane-ER contact sites in response to cholesterol accumulation in the plasma membrane. Mice lacking Aster-B are deficient in adrenal cholesterol ester storage and steroidogenesis because of an inability to transport cholesterol from SR-BI to the ER. These findings identify a nonvesicular pathway for plasma membrane to ER sterol trafficking in mammals.

Tags
Master Mix

Share this article

Published
October, 2018

Source

Products used in this publication

  • default alt
    DMMLD2D600
    Universal Mastermix 7.5ml

Events

 See all events

News

 See all news

Applications

 See all applications



The European Regional Development Fund and Wallonia are investing in your future.

Extension of industrial buildings and new laboratories.



  ABOUT SSL CERTIFICATES

         Site map   |   Contact us   |   Conditions of sales   |   Conditions of purchase   |   Privacy policy   |   Diagenode Diagnostics