title: A two-photon fluorescent probe for lipid raft imaging: C-laurdan.
abstract: The lipid-rafts hypothesis proposes that naturally occurring lipid aggregates exist in the plane of membrane that are involved in signal transduction, protein sorting, and membrane transport. To understand their roles in cell biology, a direct visualization of such domains in living cells is essential. For this purpose, 6-dodecanoyl-2-(dimethylamino)naphthalene (laurdan), a membrane probe that is sensitive to the polarity of the membrane, has often been used. We have synthesized and characterized 6-dodecanoyl-2-[N-methyl-N-(carboxymethyl)amino]naphthalene (C-laurdan), which has the advantages of greater sensitivity to the membrane polarity, a brighter two-photon fluorescence image, and reflecting the cell environment more accurately than laurdan. Lipid rafts can be visualized by two-photon microscopy by using C-laurdan as a probe. Our results show that the lipid rafts cover 38 % of the cell surface.
authors.affiliation: Department of Chemistry and Center for Electro- and Photo-Responsive Molecules, Korea University, 1-Anamdong, Seoul 136-701, Korea.
authors.forename: Hwan Myung
authors.initials: HM
authors.lastname: Kim
authors.forename: Hyo-Jung
authors.initials: HJ
authors.lastname: Choo
authors.forename: Soon-Young
authors.initials: SY
authors.lastname: Jung
authors.forename: Young-Gyu
authors.initials: YG
authors.lastname: Ko
authors.forename: Won-Hwa
authors.initials: WH
authors.lastname: Park
authors.forename: Seung-Joon
authors.initials: SJ
authors.lastname: Jeon
authors.forename: Chul Hoon
authors.initials: CH
authors.lastname: Kim
authors.forename: Taiha
authors.initials: T
authors.lastname: Joo
authors.forename: Bong Rae
authors.initials: BR
authors.lastname: Cho
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives* / Q000737:chemistry; D002138:Calibration; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D005456:Fluorescent Dyes / Q000494:pharmacology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007848:Laurates / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D021962:Membrane Microdomains / Q000737:chemistry*; D008853:Microscopy; D008856:Microscopy, Fluorescence; D008956:Models, Chemical; D017785:Photons; D013053:Spectrophotometry / Q000379:methods; D014867:Water / Q000737:chemistry
chemical_list: D005456:Fluorescent Dyes; D007848:Laurates; D008055:Lipids; D014867:Water; D015081:2-Naphthylamine; C065580:laurdan