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A new adenosyl-alkaloid, ostrerine A (1), has been isolated along with an amino acid, tryptophan (2) and a ribonucleoside, 2′-deoxythymidine (3) from the Quanzhou marine mollusk, Ostrea rivularis , and the structures were elucidated by 1D and 2D NMR experiments, including 1 H- 1 H COSY, TOCSY, NOESY, HMQC, and HMBC methods. [ABSTRACT FROM AUTHOR]

The adrenergic system is a neuromodulatory system whose endogenous ligands are considered to be the catecholamines norepinephrine (NE) and epinephrine (E). Evidence suggests that the catecholamine dopamine (DA) may also activate adrenergic signaling. Further, tyramine (TA) and octopamine (OA) are other monoamines that can be produced in catecholaminergic cells when tyrosine hydroxylase activity is low or absent, as in some genetic mouse models of adrenergic function. Here, we systematically examine the ability of these l-tyrosine-derived monoamines to activate all 10 known isoforms of the cloned mouse adrenergic receptors expressed in Chinese hamster ovary cells. In comparison to NE or E, DA is nearly as efficacious in this system but is from 1 to 4 orders of magnitude less potent. In comparison to DA, OA has roughly equivalent potency but is usually only a partial agonist. TA is either very weak or lacks agonism. Of note, all three mouse α1 receptors increase cAMP, in contrast to results reported for human α1d receptors. In addition, a 12-amino acid hemagglutinin epitope tag added to the N-terminus of α2 receptors selectively enhances the potency of NE ~10- to 100-fold, indicating that caution should be applied when interpreting physiological results from experiments using modified receptors. [Copyright &y& Elsevier]

The Human Genome Project has provided abundant gene sequence information on human and important model organisms. The chicken is well positioned from an evolutionary standpoint to serve as a link between higher and lower organisms, particularly mammals, and amphibia and fish. In this study we used stringent criteria to select 565 triples of chicken, human, and mouse candidate orthologs. We analyze the sequences with respect to nucleotide and amino acid similarities. This analysis also allows measurement of evolutionary distances of different proteins. We found that chicken-human and chicken-mouse sequence identities are highly correlated; similarly for chicken-human and chicken-mouse evolutionary distances. With chicken as the out-group, we found that mouse has a higher substitution rate than human, supporting the generation-time effect hypothesis. We also described the transversion bias, which is the preference for some transversions than others in nucleotide substitutions. We demonstrated that there are statistically significant properties in the differences of orthologous sequences. The differential patterns, in combination with sequence similarity analysis, may lead to the identification of genes that are very divergent from the mammalian orthologs. [ABSTRACT FROM AUTHOR]