The domain structures of lipid-free and lipid-bound apolipoprotein A-I (apo A-I) containing reduced and oxidized methionines were analyzed by limited proteolysis. Lipid-free apo A-I is cleaved primarily in the extreme carboxy-terminus and, to a much lesser extent, in the central region of the protein between residues 115 and 136. Oxidation of methionines 112 and 148 to the corresponding sulfoxides in putative amphipathic helices 4 (P99-E120) and 6 (P143-A164), respectively, causes helices 1 (L44-G65), 2 (P66-S87), and 7 (P165-G186) to become susceptible to protease digestion. These results are consistent with a discrete, globular tertiary structure for the lipid-free protein minimally formed from amphipathic helices 1, 2, 4, 6, and 7. In distinct contrast to lipid-free apo A-I, lipid-bound apo A-I is most susceptible to cleavage in the extreme amino-terminus and, to a lesser extent, in both the central and carboxy-terminal regions. The observed cleavage pattern for the reduced lipid-bound protein supports the existence of many of the turns between helices predicted by sequence analysis of the lipid-bound protein. Methionine oxidation of lipid-bound protein results in a decreased protease susceptibility in the extreme amino-terminus and a concomitant increase in protease susceptibility in the central and carboxy-terminal regions. The results from methionine oxidation indicate the oxidation state of the protein is an important determinant in defining the conformation of both lipid-free and lipid-bound apo A-I.

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There is increasing pressure for neuroscientists to communicate their research and the societal implications of their findings to the public. Communicating science is challenging and the transformation of communication by digital and interactive media makes the challenge even greater. To successfully facilitate dialogue with the public in this new media landscape we suggest three courses of action for the neuroscience community: a cultural shift that explicitly recognizes and rewards public outreach, the identification and development of neuroscience communication experts, and ongoing empirical research on public communication of neuroscience."That science has become more difficult for nonspecialists to understand is a truth universally acknowledged." 1 Neuroscientists are in a tough spot. With the development of powerful new tools, neuroscientists are gaining a better understanding of the biology of the brain every day. At the same time, this progress is prompting many questions about the personal, social, moral and spiritual choices that humans make. These factors conspire to place increasing pressure on neuroscientists to discuss both their scientific research and the ethical implications of their findings. It is the interactions between neuroscience and society, and the debates triggered by the social implications of neuroscience findings after all, that ultimately inform public policy 2, 3 .While translating and disseminating new knowledge is a fundamental responsibility for all scientists, neuroscience is among several scientific disciplines that are particularly prone to misinformation and inaccurate reporting. Sensational media headlines that evoke mind reading, a neurogenetic basis for fidelity or voting patterns, memory boosters for the healthy, and miracle cures for sensory and movement disorders are but a few examples. Without accurate and sufficient context, the public -who are naturally interested in diseases and cures, especially with regard to common and devastating brain disorders -may accept these simplistic messages uncritically 4 . The power of brain imaging techniques such as functional Magnetic Resonance Imaging further feeds into this problem, with the potential for brain scan images to create beliefs and biases in the laboratory, the clinic, and courtroom [5][6][7] .The interest in the neurological basis of individual and social behavior has also spawned a staggering number of neurologisms -new terms for the complex and varied phenomena arising at the intersection of brain science and society -including neuroethics, neuromyths, neurorealism, neuromarketing and, of course, neurotalk. Some, like neurotalk and neuroethics, bring ideas for a dedicated new practical and scholarly effort to the foreground; while others, like neurorealism 8 and neuromyths 9 highlight how the seductive allure of neuroscience explanations can confer an unwarranted sense of objectivity based on the general hype that surrounds contemporary science and technology 10 .Not all science in the public sphere is tr...