Liquid-Liquid Domains in Bilayers Detected by Wide Angle X-Ray Scattering Export

@article{citeulike:4369577, abstract = {Wide angle x-ray scattering (WAXS) from oriented lipid multilayers is used to examine liquid-ordered (Lo)/liquid-disordered (Ld) phase coexistence in the system 1,2-dioleoyl-sn-glycero-3-phosphocholine/1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol (DOPC/DPPC/Chol), which is a model for the outer leaflet of the animal cell plasma membrane. Using the method of analysis developed in the accompanying work, we find that two orientational distributions are necessary to fit the WAXS data at lower temperatures, whereas only one distribution is needed at temperatures higher than the miscibility transition temperature, Tmix=2535°C (for 1:1 DOPC/DPPC with 15\%, 20\%, 25\%, and 30\% Chol). We propose that the necessity for two distributions is a criterion for coexistence of Lo domains with a high Sx-ray order parameter and Ld domains with a lower order parameter. This criterion is capable of detecting coexistence of small domains or rafts that the conventional x-ray criterion of two lamellar D spacings may not. Our Tmix values tend to be slightly larger than published NMR results and microscopy results when the fluorescence probe artifact is considered. This is consistent with the sensitivity of WAXS to very short time and length scales, which makes it more capable of detecting small, short-lived domains that are likely close to Tmix.}, author = {Mills, Thalia T. and Tristram-Nagle, Stephanie and Heberle, Frederick A. and Morales, Nelson F. and Zhao, Jiang and Wu, Jing and Toombes, Gilman E. and Nagle, John F. and Feigenson, Gerald W.}, citeulike-article-id = {4369577}, citeulike-linkout-0 = {http://www.cell.com/biophysj/abstract/S0006-3495(08)70243-1}, day = {15}, keywords = {domain, liquid-liquid, membrane, mills08pdf, saxs}, month = {July}, number = {2}, pages = {682--690}, posted-at = {2009-04-20 18:52:56}, priority = {2}, title = {Liquid-Liquid Domains in Bilayers Detected by Wide Angle X-Ray Scattering}, url = {http://www.cell.com/biophysj/abstract/S0006-3495(08)70243-1}, volume = {95}, year = {2008} }

TY - JOUR ID - citeulike:4369577 L3 - citeulike-article-id:4369577 N2 - Wide angle x-ray scattering (WAXS) from oriented lipid multilayers is used to examine liquid-ordered (Lo)/liquid-disordered (Ld) phase coexistence in the system 1,2-dioleoyl-sn-glycero-3-phosphocholine/1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol (DOPC/DPPC/Chol), which is a model for the outer leaflet of the animal cell plasma membrane. Using the method of analysis developed in the accompanying work, we find that two orientational distributions are necessary to fit the WAXS data at lower temperatures, whereas only one distribution is needed at temperatures higher than the miscibility transition temperature, Tmix=2535°C (for 1:1 DOPC/DPPC with 15%, 20%, 25%, and 30% Chol). We propose that the necessity for two distributions is a criterion for coexistence of Lo domains with a high Sx-ray order parameter and Ld domains with a lower order parameter. This criterion is capable of detecting coexistence of small domains or rafts that the conventional x-ray criterion of two lamellar D spacings may not. Our Tmix values tend to be slightly larger than published NMR results and microscopy results when the fluorescence probe artifact is considered. This is consistent with the sensitivity of WAXS to very short time and length scales, which makes it more capable of detecting small, short-lived domains that are likely close to Tmix. IS - 2 EP - 690 TI - Liquid-Liquid Domains in Bilayers Detected by Wide Angle X-Ray Scattering VL - 95 SP - 682 KW - domain KW - liquid-liquid KW - membrane KW - mills08pdf KW - saxs AU - Mills, Thalia AU - Tristram-Nagle, Stephanie AU - Heberle, Frederick AU - Morales, Nelson AU - Zhao, Jiang AU - Wu, Jing AU - Toombes, Gilman AU - Nagle, John AU - Feigenson, Gerald PY - 2008/07/15/ UR - http://www.cell.com/biophysj/abstract/S0006-3495(08)70243-1 ER -