Naofumi Shimokawa

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Recently, Rozovsky et al. reported on the morphology and dynamics of superstructures in three-component lipid bilayers containing saturated lipid, unsaturated lipid, and cholesterol (Rozovsky, S.; Kaizuka, Y.; Groves, J. T. J. Am. Chem. Soc. 2005, 127, 36). We suggest that the observed sequence of the striped-to-hexagonal morphological transition in mixed(More)
Porcine growth hormone (PGH) precursor cDNAs were cloned from a pituitary cDNA library constructed in lambda gt11 by immunoscreening. One of the three clones characterized contained an entire nucleotide sequence for the 216-amino-acid precursor molecule. The deduced amino-acid sequence of PGH confirmed the sequence previously reported for that of the(More)
Macro-phase separation in mixed lipid membranes containing the hybrid lipid palmitoyloleoylphosphatidylcholine (POPC) was observed by fluorescent and confocal laser scanning microscopy. In a binary system consisting of the saturated lipid dipalmitoylphosphatidylcholine (DPPC) and the hybrid lipid POPC, the hybrid lipid forms a liquid-disordered (Ld) phase.(More)
Phase separation in lipid bilayers that include negatively charged lipids is examined experimentally. We observed phase-separated structures and determined the membrane miscibility temperatures in several binary and ternary lipid mixtures of unsaturated neutral lipid, dioleoylphosphatidylcholine (DOPC), saturated neutral lipid,(More)
Cholesterol plays an important role in the interaction of Alzheimer's amyloid beta (Aβ) with cell membranes, an important event in Aβ-induced cytotoxicity. However, it is not fully understood how cholesterol influences the association of Aβ with membrane lateral compartments. We have shown that by modulating membrane fluidity, cholesterol decreased peptide(More)
Biomembranes, which are mainly composed of neutral and charged lipids, exhibit a large variety of functional structures and dynamics. Here, we report a coarse-grained molecular dynamics (MD) simulation of the phase separation and morphological dynamics in charged lipid bilayer vesicles. The screened long-range electrostatic repulsion among charged head(More)
We investigated the phase behavior of lipid membranes containing fatty acids (FAs) by microscopy and differential scanning calorimetry. We used palmitic acid (saturated FA), oleic acid (cis-isomer of unsaturated FA), elaidic acid (trans-isomer of unsaturated FA), and phytanic acid (branched FA) and examined the effects of FAs on phase-separated structures(More)
An attempt was made to clarify the relationship between the synthesis of prolactin (PRL) and its secretion during the rat estrous cycle by examining the changes in PRL messenger RNA (mRNA); PRL secretion and anterior pituitary PRL content. At various stages of the estrous cycle, pituitary and serum levels of PRL and growth hormone (GH) were measured by(More)
We propose a model describing liquid-solid phase coexistence in mixed lipid membranes by including explicitly the occurrence of a rippled phase. For a single component membrane, we employ a previous model in which the membrane thickness is used as an order parameter. As function of temperature, this model properly accounts for the phase behavior of the(More)
Chirality plays a vital role in biological membranes and has a significant effect depending on the type and arrangement of the isomer. Menthol has two typical chiral forms, d- and l-, which exhibit different behaviours. l-Menthol is known for its physiological effect on sensitivity (i.e. a cooling effect), whereas d-menthol causes skin irritation. Menthol(More)