Membrane docking mode of the C2 domain of PKCε: An infrared spectroscopy and FRET study

• The C2 domain of PKCε binds to negatively charged phospholipids but little is known so far about the docking orientation of this domain when it is bound. By using a FRET assay we have studied the binding of this domain to model membranes. We have also used ATR-Fourier transform infrared spectroscopy with polarized light (ATR-FTIR) to determine the docking mode by calculating the β-sandwich orientation when the domain is bound to different types of model membranes. The vesicle lipid compositions were: POPC/POPE/POPA (22:36:42) imitating the inner leaflet of a plasma membrane, POPC/POPA (50:50) in which POPE has been eliminated with respect to the former composition and POPC/POPE/CL (43:36:21) imitating the inner mitochondrial membrane. Results show that the β-sandwich of the PKCα-C2 domain is inclined at an angle α close to 45 to the membrane normal. Some differences were found with respect to the extent of binding as a function of phospholipid composition and small changes on secondary structure were only evident when the domain was bound to model membranes of POPC/POPA: in this case, the percentage of β-sheet of the C2 domain increases if compared with the secondary structure of the domain in the absence of vesicles. With respect to the β-sandwich orientation, when the domain is bound to POPC/POPE/CL membranes it forms an angle with the normal to the surface of the lipid bilayer (39) smaller than that one observed when the domain interacts with vesicles of POPC/POPA (49). © 2012 Elsevier B.V. All rights reserved.

Ämnesord

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

Nyckelord

ATR-IR

C2 domains

Membrane docking

PKCε

1 palmitoyl 2 oleoyl sn glycero 3 phosphate

1 palmitoyl 2 oleoyl sn glycero 3 phosphoethanolamine

2 oleoyl 1 palmitoylphosphatidylcholine

cardiolipin

glycerophospholipid

protein kinase C epsilon

unclassified drug

article

artificial membrane

cell membrane

controlled study

enzyme binding

enzyme structure

fluorescence resonance energy transfer

infrared spectroscopy

lipid bilayer

lipid composition

mathematical computing

membrane structure

mitochondrial membrane

molecular docking

priority journal

protein binding

protein lipid interaction

protein secondary structure

Adenosine

Calcium

Glycerophospholipids

Humans

Lipid Bilayers

Lipids

Mitochondrial Membranes

Models

Molecular

Models

Statistical

Molecular Conformation

Phosphatidylcholines

Phosphatidylethanolamines

Phospholipids

Protein Conformation

Protein Kinase C-epsilon

Protein Structure

Secondary

Protein Structure

Tertiary

Spectrophotometry

Infrared

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)