Science and Technology Production
Congress
Authorship
Serrano María Emilia
;
Faimberg Mijal
;
Ré Agustín Victoriano
;
CARUSO, BENJAMIN
Date
2025
Publishing House and Editing Place
Sociedad Argentina de Biofisica
ISSN
978-987-48938-3-3
Summary
Information provided by the agent in
SIGEVA
Neutral lipids (NL), such as triacylglycerols (TG) and wax esters (WE), are key constituentsof biological membranes and storage compartments. Although they do not form bilayers,their interfacial organization is fundamental to processes like lipid droplet (LD) biogenesis,where liquid NL segregate from the endoplasmic reticulum membrane to form cytosolicdroplets. However, little is known about how viscosity, internal organization, or moleculardiversity of NL lenses influence their stability and i...
Neutral lipids (NL), such as triacylglycerols (TG) and wax esters (WE), are key constituentsof biological membranes and storage compartments. Although they do not form bilayers,their interfacial organization is fundamental to processes like lipid droplet (LD) biogenesis,where liquid NL segregate from the endoplasmic reticulum membrane to form cytosolicdroplets. However, little is known about how viscosity, internal organization, or moleculardiversity of NL lenses influence their stability and interactions with phospholipids. Herewe examined the interfacial behavior of triolein (TO), triestearin (TS), stearic acid (SA), andliquid or solid WE, alone or mixed with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine(POPC). Using our model system LD biogenesis consisting on Langmuir monolayers andBrewster angle microscopy, we found that NL can transiently form highly packed films,reaching surface pressures comparable to bilayers, with metastable persistence overminutes to hours. These films exhibit marked phase heterogeneity and variable spatialconnectivity. The NL molar fration (χNL) at which material is seggregated out of themonolayer phase is considered as the NL miscibility. When mixed with POPC, miscibilitystrongly depended on NL composition and phase state. Natural neutral lipid mixtures withunsaturation levels similar to TO were less miscible (χTO=0.15) than dehydrated milk fat(χTO=0.35), which is less unsaturated. To test whether this behavior could be reproducedby simpler systems, we analyzed TO/TS/POPC mixtures. Despite having a similar overallunsaturation to natural fats, these films did not replicate their miscibility trend. Moreover,liquid WEs displayed higher miscibility (χWE=0.25) with POPC than TGs of comparableunsaturation. Together, these results highlight that chain distribution and moleculararchitecture among NL species may play a more decisive role than global unsaturation indetermining interfacial organization. Our findings open the way to further studies on howneutral lipid diversity shapes the physical landscape of biological interfaces and the earlystages of LD formation.
Show more
Show less
Key Words
Lipid Droplets BiogenesisNeutral LipidsFilms Langmuir