{"created":"2023-06-19T07:19:00.733258+00:00","id":4677,"links":{},"metadata":{"_buckets":{"deposit":"a88c72c9-fdf6-4eac-9cec-67fbfc25744a"},"_deposit":{"created_by":4,"id":"4677","owners":[4],"pid":{"revision_id":0,"type":"depid","value":"4677"},"status":"published"},"_oai":{"id":"oai:az.repo.nii.ac.jp:00004677","sets":["17:253:315","17:253:325","31:181:490"]},"author_link":["20344","20341","20340","20339","20343","20342"],"item_12_biblio_info_16":{"attribute_name":"書誌情報","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2005-03-31","bibliographicIssueDateType":"Issued"},"bibliographicPageEnd":"187","bibliographicPageStart":"183","bibliographicVolumeNumber":"9/10","bibliographic_titles":[{"bibliographic_title":"麻布大学雑誌"},{"bibliographic_title":"Journal of Azabu University","bibliographic_titleLang":"en"}]}]},"item_12_description_13":{"attribute_name":"抄録","attribute_value_mlt":[{"subitem_description":"本研究課題では,真珠層形成機構を分子レベルで明らかにするために,これらの分子の構造をウグイスガイ科を中心とした軟体動物の異なる系統間で比較し,構造の保存性に関する情報を基に分子の機能の推定を試みた。さらに,結晶形成実験を基に,3種類の真珠層形成タンパク質の機能解析を行って,分子の構造から推定される機能の検証を試みた。その結果,ナクレインのCA活性部位とN16のsulfation部位の保存性が高い反面,両成分中に存在するNG繰り返し配列部位の保存性が低いことが明らかになった。また,MSI60は,分子全体に渡って極めて保存性の高いことが明らかになった。結晶形成実験からは,ナクレイン,N16ともにアラレ石結晶の形態を制御するものの,結晶形の決定には関与しないと考えられた。これに対してMSI60は,これが存在しないと結晶の層状成長が起こらないものの,結晶形態や結晶形の制御などには関与していないことが判明した。殻体真珠層は,1)石灰化の場の形成2)カルシウムイオンと炭酸イオンの濃集3)炭酸カルシウム結晶核の形成4)結晶形の制御の各段階を経て形成される。上記の結果を基に筆者らは,真珠層形成機構を以下のように考察した。まず,石灰化の場が,MSI60を主体とした不溶性の膜により形成され,続いて,炭酸イオンとカルシウムイオンの石灰化の場への濃集が,ナクレインのCA活性部位とN16のsulfation部位の働きによって計られる。過飽和状態となった膜上で,炭酸カルシウム結晶核の形成がtemplateの働きによって起こり,この結晶核が次第に成長して,真珠層に特有の板状の形態を持つようになる。この結晶形態制御は,ナクレインとN16分子中に存在するNG繰り返し配列部位の結晶表面への吸着により遂行される。これまでに報告された10数種類の軟体動物殻体形成に関与する成分の中で,templateに相当する明確な特徴を持った成分は発見されていない。アコヤガイ真珠層中からObaraら(M.S.)により発見されたMSI25に結晶核形成を誘導する構造上の特徴が見出された。MSI25は,N末端領域に集中する酸性アミノ酸領域にカルシウムイオンを結合し,分子中に3回出現する塩基性アミノ酸領域に炭酸イオンを結合し,この2種類のイオン同士のイオン結合により炭酸カルシウム結晶核を誘導する可能性がある。この成分の機能については,現在,結晶形成実験により検証を進めている。","subitem_description_type":"Abstract"}]},"item_12_description_14":{"attribute_name":"Abstract","attribute_value_mlt":[{"subitem_description":"The organic matrix of molluscan shells is one of the best studied of all CaCO_3 biomineral structures, and about 10 genes encoding the matrix proteins have been isolated. In them, nacrein, N16 and MSI60 were reported to be involved in the nacreous layer formation of Japanese pearl oyster, Pinctada fucata. Here we report the result based on the comparative analysis of the primary structures of these 3 proteins among 10 molluscan species. In addition, cDNA cloning of the newly found 25 kDa component and new informations from in vitro studies of the crystallization experiment will be discussed. High homology was determined at CA domain of nacrein, particularly the active site of CA, and sulfation site of N16 in contrast to low homology at NG repeat region of nacrein and N16. MSI60 was highly conservative through its whole structure among 10 species. Crystallization experiment clarified that nacrein and N16 may be involved in crystal form regulation and not be in crystal nucleation. MSI60 was thought to be important as base membrane for crystal layer formation but no relation to regulation or nucleation of crystal. On the basis of these results, we proposed a new model for nacleous layer formation. According to our hypothesis, it includes the processes 1) concentration of Ca^<2+> and CO_3^<2-> ions to the site for crystal nucleation 2) crystal nucleation and 3) regulation of crystal form. For all these processes, several kinds of proteins may play important roles; 1) compartment and Ca^<2+> - and CO_3^<2-> -ion concentrators, 2) nucleator and 3) regulator. We propose MSI60 as a component for compartment, the active site of CA in nacrein as CO_3^<2-> concentrator and sulfation site of N16 as Ca^<2+> concentrator. In addition, newly found MSI25 was thought to be a candidate of nucleator as it can be a Ca^<2+> and CO_3^<2-> binding protein. We suppose nacrein and N16 as regulator through reaction of their NG repeat region and crystals. The model for nacreous layer formation will give a new insight into the process of molluscan shell formation and will give important information to CO_2 fixation by marine creatures.","subitem_description_type":"Other"}]},"item_12_description_2":{"attribute_name":"ページ属性","attribute_value_mlt":[{"subitem_description":"P(論文)","subitem_description_type":"Other"}]},"item_12_description_3":{"attribute_name":"記事種別","attribute_value_mlt":[{"subitem_description":"特集","subitem_description_type":"Other"}]},"item_12_description_34":{"attribute_name":"format","attribute_value_mlt":[{"subitem_description":"application/pdf","subitem_description_type":"Other"}]},"item_12_description_4":{"attribute_name":"Type","attribute_value_mlt":[{"subitem_description":"FEATURE ARTICLES","subitem_description_type":"Other"}]},"item_12_publisher_19":{"attribute_name":"出版者","attribute_value_mlt":[{"subitem_publisher":"麻布大学"}]},"item_12_publisher_20":{"attribute_name":"Publisher","attribute_value_mlt":[{"subitem_publisher":"Azabu University"}]},"item_12_source_id_21":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"1346-5880","subitem_source_identifier_type":"ISSN"}]},"item_12_source_id_23":{"attribute_name":"書誌レコードID","attribute_value_mlt":[{"subitem_source_identifier":"AA11561468","subitem_source_identifier_type":"NCID"}]},"item_12_text_10":{"attribute_name":"Author ID","attribute_value_mlt":[{"subitem_text_value":"000088"},{"subitem_text_value":"-"},{"subitem_text_value":"000120"}]},"item_12_text_11":{"attribute_name":"所属機関","attribute_value_mlt":[{"subitem_text_value":"環境保健学研究科"},{"subitem_text_value":"環境保健学研究科"},{"subitem_text_value":"環境保健学研究科"}]},"item_12_text_12":{"attribute_name":"Institution or Company","attribute_value_mlt":[{"subitem_text_value":"Graduate School of Environmental Health"},{"subitem_text_value":"Graduate School of Environmental Health"},{"subitem_text_value":"Graduate School of Environmental Health"}]},"item_12_text_9":{"attribute_name":"著者ID","attribute_value_mlt":[{"subitem_text_value":"000088"},{"subitem_text_value":"-"},{"subitem_text_value":"000120"}]},"item_12_version_type_29":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_12_version_type_30":{"attribute_name":"text version","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"佐俣, 哲郎"},{"creatorName":"サマタ, テツロウ","creatorNameLang":"ja-Kana"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"中明, 賢二"},{"creatorName":"ナカアキ, ケンジ","creatorNameLang":"ja-Kana"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"其木, 茂則"},{"creatorName":"ソノキ, シゲノリ","creatorNameLang":"ja-Kana"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Samata, Tetsuro","creatorNameLang":"en"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Nakaaki, Kenji","creatorNameLang":"en"}],"nameIdentifiers":[{}]},{"creatorNames":[{"creatorName":"Sonoki, Sigenori","creatorNameLang":"en"}],"nameIdentifiers":[{}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_date","date":[{"dateType":"Available","dateValue":"2004-01-01"}],"displaytype":"detail","filename":"bull_jau_vol9-10-183.pdf","filesize":[{"value":"1.1 MB"}],"format":"application/pdf","licensetype":"license_note","mimetype":"application/pdf","url":{"label":"bull_jau_vol9-10-183.pdf","url":"https://az.repo.nii.ac.jp/record/4677/files/bull_jau_vol9-10-183.pdf"},"version_id":"a2c206d0-1562-4fa6-ab63-e0d4cec1d800"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"jpn"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"departmental bulletin paper","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"軟体動物殻体真珠屑形成の分子機構の解明","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"軟体動物殻体真珠屑形成の分子機構の解明"},{"subitem_title":"Elucidation of molecular mechanism of molluscan nacreous layer formation","subitem_title_language":"en"}]},"item_type_id":"12","owner":"4","path":["315","325","490"],"pubdate":{"attribute_name":"公開日","attribute_value":"2004-01-01"},"publish_date":"2004-01-01","publish_status":"0","recid":"4677","relation_version_is_last":true,"title":["軟体動物殻体真珠屑形成の分子機構の解明"],"weko_creator_id":"4","weko_shared_id":4},"updated":"2023-06-19T07:48:37.434775+00:00"}