Barnacle attachment to various foreign materials in water is guided by an extracellular multiprotein complex. A 19 kDa cement protein was purified from the Megabalanus rosa cement, and its cDNA was cloned and sequenced. The gene was expressed only in the basal portion of the animal, where the histologically identified cement gland is located. The sequence of the protein showed no homology to other known proteins in the databases, indicating that it is a novel protein. Agreement between the molecular mass determined by MS and the molecular weight estimated from the cDNA indicated that the protein bears no post‐translational modifications. The bacterial recombinant was prepared in soluble form under physiologic conditions, and was demonstrated to have underwater irreversible adsorption activity to a variety of surface materials, including positively charged, negatively charged and hydrophobic ones. Thus, the function of the protein was suggested to be coupling to foreign material surfaces during underwater attachment. Homologous genes were isolated from Balanus albicostatus and B. improvisus, and their amino acid compositions showed strong resemblance to that of M. rosa, with six amino acids, Ser, Thr, Ala, Gly, Val and Lys, comprising 66–70% of the total, suggesting that such a biased amino acid composition may be important for the function of this protein.

Recent studies have revealed that bile acids (BAs) are not only facilitators of dietary lipid absorption but also important signaling molecules exerting multiple physiological functions. Some major signaling pathways involving the nuclear BAs receptor farnesoid X receptor and the G protein-coupled BAs receptor TGR5/M-BAR have been identified to be the targets of BAs. BAs regulate their own homeostasis via signaling pathways. BAs also affect diverse metabolic pathways including glucose metabolism, lipid metabolism and energy expenditure. This paper suggests the mechanism of controlling metabolism via BA signaling and demonstrates that BA signaling is an attractive therapeutic target of the metabolic syndrome.

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Disruption of iron metabolism is closely related to metabolic diseases. Iron deficiency is frequently associated with obesity and hepatic steatosis. However, the effects of iron supplementation on obesity and energy metabolism remain unclear. Here we show that a high-fat diet supplemented with iron reduces body weight gain and hepatic lipid accumulation in mice. Iron supplementation was found to reduce mitochondrial morphological abnormalities and upregulate gene transcription involved in mitochondrial function and beta oxidation in the liver and skeletal muscle. In both these tissues, iron supplementation increased the expression of genes involved in heme or iron–sulfur (Fe–S) cluster synthesis. Heme and Fe–S cluster, which are iron prosthetic groups contained in electron transport chain complex subunits, are essential for mitochondrial respiration. The findings of this study demonstrated that iron regulates mitochondrial signaling pathways—gene transcription of mitochondrial component molecules synthesis and their energy metabolism. Overall, the study elucidates the molecular basis underlying the relationship between iron supplementation and obesity and hepatic steatosis progression, and the role of iron as a signaling molecule.

Free radical polymerization under ambient conditions gives very low‐molecular weight homopolymer of isopropenyl acetate (IPAc). On the other hand, poly (isopropenyl acetate) (PIPAc) with a weight average molecular weight over 104 was found to be synthesized by high‐pressure (1 GPa) radical polymerization. Poly(isopropenyl alcohol) (PIPOH) was then derived from PIPAc by saponification. The structure and properties of PIPAc and PIPOH were investigated using X‐ray diffraction, thermal analyses, X‐ray photoelectron spectroscopy, and dynamic contact angles. Though PIPOH is insoluble in water, the surface free energy (55 mJ/m2) was comparable with that of poly(vinyl alcohol). To utilize the peculiar combination of “aqueous insolubileity and high hydrophilicity” of PIPOH, biocompatibilities of PIPOH surface was investigated. The PIPOH surface was found to show high repellencies to albumin adsorption, whole thrombogenesis, and cell adhesion. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 754–761, 2009