Intermolecular hydrogen bonding between lipids: influence on organization and function of lipids in membranes

1980 ◽  
Vol 58 (10) ◽  
pp. 755-770 ◽  
Author(s):  
Joan M. Boggs

Biological membranes have unique lipid compositions suggesting a specific role for many lipids. Evidence is reviewed concerning the intermolecular forces between glycero- and sphingolipids and cholesterol, the dependence of many of these interactions on the state of ionization of lipids, pH, ionic strength, and divalent cation concentration. The effect of intermolecular interactions between certain lipids on lipid clustering, interaction with cholesterol, on the conformation of proteins, and on transitions to the hexagonal phase is considered. Other forces which cause lipid phase separation or clustering are discussed. It is concluded that lipids are in dynamic equilibrium with their environment and can act as receptors for certain intra- or extracellular stimuli, which they can translate into a response by undergoing changes in fluidity, phase transitions, or phase separation.

2021 ◽  
Vol 22 (5) ◽  
pp. 2776
Author(s):  
Selma Yilmaz Dejgaard ◽  
John F. Presley

Historically, studies of intracellular membrane trafficking have focused on the secretory and endocytic pathways and their major organelles. However, these pathways are also directly implicated in the biogenesis and function of other important intracellular organelles, the best studied of which are peroxisomes and lipid droplets. There is a large recent body of work on these organelles, which have resulted in the introduction of new paradigms regarding the roles of membrane trafficking organelles. In this review, we discuss the roles of membrane trafficking in the life cycle of lipid droplets. This includes the complementary roles of lipid phase separation and proteins in the biogenesis of lipid droplets from endoplasmic reticulum (ER) membranes, and the attachment of mature lipid droplets to membranes by lipidic bridges and by more conventional protein tethers. We also discuss the catabolism of neutral lipids, which in part results from the interaction of lipid droplets with cytosolic molecules, but with important roles for both macroautophagy and microautophagy. Finally, we address their eventual demise, which involves interactions with the autophagocytotic machinery. We pay particular attention to the roles of small GTPases, particularly Rab18, in these processes.


Biochemistry ◽  
1977 ◽  
Vol 16 (11) ◽  
pp. 2325-2329 ◽  
Author(s):  
J. M. Boggs ◽  
D. D. Wood ◽  
M. A. Moscarello ◽  
D. Papahadjopoulos

2020 ◽  
Author(s):  
J. K. Chung ◽  
W. Y. C. Huang ◽  
C. B. Carbone ◽  
L. M. Nocka ◽  
A. N. Parikh ◽  
...  

AbstractLipid miscibility phase separation has long been considered to be a central element of cell membrane organization. More recently, protein condensation phase transitions, into three-dimensional droplets or in two-dimensional lattices on membrane surfaces, have emerged as another important organizational principle within cells. Here, we reconstitute the LAT:Grb2:SOS protein condensation on the surface of giant unilamellar vesicles capable of undergoing lipid phase separations. Our results indicate that assembly of the protein condensate on the membrane surface can drive lipid phase separation. This phase transition occurs isothermally and is governed by tyrosine phosphorylation on LAT. Furthermore, we observe that the induced lipid phase separation drives localization of the SOS substrate, K-Ras, into the LAT:Grb2:SOS protein condensate.Statement of SignificanceProtein condensation phase transitions are emerging as an important organizing principles in cells. One such condensate plays a key role in T cell receptor signaling. Immediately after receptor activation, multivalent phosphorylation of the adaptor protein LAT at the plasma membrane leads to networked assembly of a number of signaling proteins into a two-dimensional condensate on the membrane surface. In this study, we demonstrate that LAT condensates in reconstituted vesicles are sufficient to drive lipid phase separation. This lipid reorganization drives another key downstream signaling molecule, Ras, into the LAT condensates. These results show that the LAT condensation phase transition, which is actively controlled by phosphorylation reactions, extends its influence to control lipid phase separation in the underlying membrane.


2019 ◽  
Vol 117 (7) ◽  
pp. 1215-1223 ◽  
Author(s):  
Yang Liu ◽  
Jonathan Barnoud ◽  
Siewert J. Marrink

2013 ◽  
Vol 135 (4) ◽  
pp. 1185-1188 ◽  
Author(s):  
Christine S. Scheve ◽  
Paul A. Gonzales ◽  
Noor Momin ◽  
Jeanne C. Stachowiak

2009 ◽  
Vol 424 (2) ◽  
pp. 163-167 ◽  
Author(s):  
Ilya Levental ◽  
Fitzroy J. Byfield ◽  
Pramit Chowdhury ◽  
Feng Gai ◽  
Tobias Baumgart ◽  
...  

Cell-derived GPMVs (giant plasma-membrane vesicles) enable investigation of lipid phase separation in a system with appropriate biological complexity under physiological conditions, and in the present study were used to investigate the cholesterol-dependence of domain formation and stability. The cholesterol level is directly related to the abundance of the liquid-ordered phase fraction, which is the majority phase in vesicles from untreated cells. Miscibility transition temperature depends on cholesterol and correlates strongly with the presence of detergent-insoluble membrane in cell lysates. Fluorescence correlation spectroscopy reveals two distinct diffusing populations in phase-separated cell membrane-derived vesicles whose diffusivities correspond well to diffusivities in both model systems and live cells. The results of the present study extend previous observations in purified lipid systems to the complex environment of the plasma membrane and provide insight into the effect of cholesterol on lipid phase separation and abundance.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Kathi Scheinpflug ◽  
Michaela Wenzel ◽  
Oxana Krylova ◽  
Julia E. Bandow ◽  
Margitta Dathe ◽  
...  

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