title: Transbilayer lipid interactions mediate nanoclustering of lipid-anchored proteins.
abstract: Understanding how functional lipid domains in live cell membranes are generated has posed a challenge. Here, we show that transbilayer interactions are necessary for the generation of cholesterol-dependent nanoclusters of GPI-anchored proteins mediated by membrane-adjacent dynamic actin filaments. We find that long saturated acyl-chains are required for forming GPI-anchor nanoclusters. Simultaneously, at the inner leaflet, long acyl-chain-containing phosphatidylserine (PS) is necessary for transbilayer coupling. All-atom molecular dynamics simulations of asymmetric multicomponent-membrane bilayers in a mixed phase provide evidence that immobilization of long saturated acyl-chain lipids at either leaflet stabilizes cholesterol-dependent transbilayer interactions forming local domains with characteristics similar to a liquid-ordered (lo) phase. This is verified by experiments wherein immobilization of long acyl-chain lipids at one leaflet effects transbilayer interactions of corresponding lipids at the opposite leaflet. This suggests a general mechanism for the generation and stabilization of nanoscale cholesterol-dependent and actin-mediated lipid clusters in live cell membranes.
authors.affiliation: National Centre for Biological Sciences (TIFR), Bellary Road, Bangalore 560 065, India; Shanmugha Arts, Science, Technology & Research Academy, Thanjavur 613401, India.
authors.forename: Riya
authors.initials: R
authors.lastname: Raghupathy
authors.affiliation: National Centre for Biological Sciences (TIFR), Bellary Road, Bangalore 560 065, India; Shanmugha Arts, Science, Technology & Research Academy, Thanjavur 613401, India.
authors.forename: Anupama Ambika
authors.initials: AA
authors.lastname: Anilkumar
authors.affiliation: Raman Research Institute, C.V. Raman Avenue, Bangalore 560 080, India; Tampere University of Technology, Korkeakoulunkatu 10, 33720 Tampere, Finland.
authors.forename: Anirban
authors.initials: A
authors.lastname: Polley
authors.affiliation: Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu 180001, India.
authors.forename: Parvinder Pal
authors.initials: PP
authors.lastname: Singh
authors.affiliation: Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu 180001, India.
authors.forename: Mahipal
authors.initials: M
authors.lastname: Yadav
authors.affiliation: Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Johnson
authors.affiliation: Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, USA.
authors.forename: Sharad
authors.initials: S
authors.lastname: Suryawanshi
authors.affiliation: Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu 180001, India.
authors.forename: Varma
authors.initials: V
authors.lastname: Saikam
authors.affiliation: Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu 180001, India.
authors.forename: Sanghapal D
authors.initials: SD
authors.lastname: Sawant
authors.affiliation: National Centre for Biological Sciences (TIFR), Bellary Road, Bangalore 560 065, India; Manipal University, Madhav Nagar, Manipal 576104, Karnataka, India.
authors.forename: Aniruddha
authors.initials: A
authors.lastname: Panda
authors.affiliation: Wayne State University, 5101 Cass Avenue, Detroit, MI 48202, USA.
authors.forename: Zhongwu
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu 180001, India.
authors.forename: Ram A
authors.initials: RA
authors.lastname: Vishwakarma
authors.affiliation: National Centre for Biological Sciences (TIFR), Bellary Road, Bangalore 560 065, India; Raman Research Institute, C.V. Raman Avenue, Bangalore 560 080, India. Electronic address: madan@ncbs.res.in.
authors.forename: Madan
authors.initials: M
authors.lastname: Rao
authors.affiliation: National Centre for Biological Sciences (TIFR), Bellary Road, Bangalore 560 065, India; Institute for Stem Cell Biology and Regenerative Medicine, Bellary Road, Bangalore 560 065, India. Electronic address: mayor@ncbs.res.in.
authors.forename: Satyajit
authors.initials: S
authors.lastname: Mayor
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D016466:CHO Cells; D002462:Cell Membrane / Q000378:metabolism; D003412:Cricetulus; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D058635:Lipid-Linked Proteins / Q000378:metabolism*; D056004:Molecular Dynamics Simulation; D010718:Phosphatidylserines / Q000378:metabolism
chemical_list: D000199:Actins; D017261:Glycosylphosphatidylinositols; D058635:Lipid-Linked Proteins; D010718:Phosphatidylserines