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Title: Engineering lipid structure for recognition of the liquid ordered membrane phase

Abstract

The selective partitioning of lipid components in phase-separated membranes is essential for domain formation involved in cellular processes. Identifying and tracking the movement of lipids in cellular systems would be improved if we understood how to achieve selective affinity between fluorophore-labeled lipids and membrane assemblies. Furthermore, we investigated the structure and chemistry of membrane lipids to evaluate lipid designs that partition to the liquid ordered (L o) phase. A range of fluorophores at the headgroup position and lengths of PEG spacer between the lipid backbone and fluorophore were examined. On a lipid body with saturated palmityl or palmitoyl tails, we found that although the lipid tails can direct selective partitioning to the L o phase through favorable packing interactions, headgroup hydrophobicity can override the partitioning behavior and direct the lipid to the disordered membrane phase (L d). The PEG spacer can serve as a buffer to mute headgroup–membrane interactions and thus improve L o phase partitioning, but its effect is limited with strongly hydrophobic fluorophore headgroups. We present a series of lipid designs leading to the development of novel fluorescently labeled lipids with selective affinity for the L o phase.

Authors:
 [1];  [2];  [3];  [4];  [2]
  1. Sandia National Lab. (SNL-CA), Livermore, CA (United States); The Univ. of Texas at Austin, Austin, TX (United States)
  2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
  3. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  4. The Univ. of Texas at Austin, Austin, TX (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-CA), Livermore, CA (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1338315
Report Number(s):
SAND-2016-7156J
Journal ID: ISSN 0743-7463; 646063; TRN: US1701691
Grant/Contract Number:
AC04-94AL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Langmuir
Additional Journal Information:
Journal Volume: 32; Journal Issue: 47; Journal ID: ISSN 0743-7463
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES

Citation Formats

Bordovsky, Stefan S., Wong, Christopher S., Bachand, George D., Stachowiak, Jeanne C., and Sasaki, Darryl Y. Engineering lipid structure for recognition of the liquid ordered membrane phase. United States: N. p., 2016. Web. doi:10.1021/acs.langmuir.6b02636.
Bordovsky, Stefan S., Wong, Christopher S., Bachand, George D., Stachowiak, Jeanne C., & Sasaki, Darryl Y. Engineering lipid structure for recognition of the liquid ordered membrane phase. United States. doi:10.1021/acs.langmuir.6b02636.
Bordovsky, Stefan S., Wong, Christopher S., Bachand, George D., Stachowiak, Jeanne C., and Sasaki, Darryl Y. 2016. "Engineering lipid structure for recognition of the liquid ordered membrane phase". United States. doi:10.1021/acs.langmuir.6b02636. https://www.osti.gov/servlets/purl/1338315.
@article{osti_1338315,
title = {Engineering lipid structure for recognition of the liquid ordered membrane phase},
author = {Bordovsky, Stefan S. and Wong, Christopher S. and Bachand, George D. and Stachowiak, Jeanne C. and Sasaki, Darryl Y.},
abstractNote = {The selective partitioning of lipid components in phase-separated membranes is essential for domain formation involved in cellular processes. Identifying and tracking the movement of lipids in cellular systems would be improved if we understood how to achieve selective affinity between fluorophore-labeled lipids and membrane assemblies. Furthermore, we investigated the structure and chemistry of membrane lipids to evaluate lipid designs that partition to the liquid ordered (Lo) phase. A range of fluorophores at the headgroup position and lengths of PEG spacer between the lipid backbone and fluorophore were examined. On a lipid body with saturated palmityl or palmitoyl tails, we found that although the lipid tails can direct selective partitioning to the Lo phase through favorable packing interactions, headgroup hydrophobicity can override the partitioning behavior and direct the lipid to the disordered membrane phase (Ld). The PEG spacer can serve as a buffer to mute headgroup–membrane interactions and thus improve Lo phase partitioning, but its effect is limited with strongly hydrophobic fluorophore headgroups. We present a series of lipid designs leading to the development of novel fluorescently labeled lipids with selective affinity for the Lo phase.},
doi = {10.1021/acs.langmuir.6b02636},
journal = {Langmuir},
number = 47,
volume = 32,
place = {United States},
year = 2016,
month = 8
}

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