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 神経医学研究でご活躍中のDominique Aunis 博士が、1月初旬に東京にみえます。

 Domninique Aunis 博士は、現在ストラスブルグのフランス国立保健医学研究所(Institut National de la Sante et de la Recherche Medicale)の所長を務めて
います。神経細胞の細胞骨格制御や、Dopamine-β-hydroxylase、Chromogranin の研究で知られる方ですが、今回は下記のように、Chromogranin 由来の新しいペプチドに関する講演をして下さいます。

日 時:1月12日(水)午後4時から5時半頃
場 所:理学部2号館405号室(生物学第2講義室)
演 題:Neuroimmunity : new peptides derived from chromogranins

Chromogranins are acidic&s_comma; glycoproteins discovered 30 years ago : they are present in secretory granules in most endocrine and neuroendocrine cells and in neurons. They are also expressed in many tumoral tissues of endocrine origin. In chromaffin cells of adrenal glands where they are highly concentrated&s_comma; chromogranins are stored with catecholamines ; they are released during stress situation and recovered into circulation
together with stress hormones. In secretory granules&s_comma; chromogranins are processed into low molecular weight peptides&s_comma; the function of these peptides however being not yet identified. We have recently looked for post-translational modifications of Chromogranin A purified from bovine chromaffin granules and from the urine of patients with carcinoid tumors.

Also recently data from my laboratory have shown that chromogranin-derived peptides possess potent antibacterial and antifungal activities with specific spectrum of activity. We have analyzed the structural relationship
between these peptides and their activities&s_comma; and found that some peptides are related to cecropins. We have also found that chromogranin-derived peptides are released from immunocytes and are detectable in many infectious fluids. We recently observed that chromogranin-derived peptides are able to activate cultured microglial cells from rat brain inducing the concomitant release of diffusible&s_comma; heat stable neurotoxic factors. The
conditioned culture medium collected from microglial cells incubated with chromogranin provokes the activation of specific intracellular pathways and the neuronal death by apoptosis. The significance of this finding may be of importance with regard to the presence of chromogranin and chromogranin-related peptides in senile plaques in the brain of Alzheimer patients.

世話人:室伏きみ子 Kimiko Murofushi&s_comma;Ph.D.
Department of Boiology&s_comma; Faculty of Science
Ochanomizu University

Tetsuyuki KOBAYASHI&s_comma; Ph.D.
Department of Biology&s_comma; Ochanomizu University
2-1-1 Ohtsuka&s_comma; Bunkyo-ku&s_comma; Tokyo 112-8610 Japan
Phone/Fax +81-3-5978-2604
E-mail tetkoba@cc.ocha.ac.jp