Michio Ogawa

Isolation and chromosomal assignment of a novel human gene, CORO1C, homologous to coronin-like actin-binding proteins.

We have isolated a gene, termed CORO1C (human coronin-like actin-binding protein 1C), that encodes a new member of the coronin-like family of proteins. The cDNA consists of 3,857 nucleotides, with an open reading frame of 1,422 bp encoding a 474 amino acid protein. The deduced amino acid sequence shared 65% identity with p57 (human coronin-like actin-binding protein), as well as 46% identity with coronin, a protein first isolated from the slime mold Dictyostelium discoideum. Computer analysis predicted that the product of the CORO1C gene would contain five WD repeats in its N-terminal region and a coiled-coil motif in its C-terminal region, both of which are conserved among coronin-like proteins. CORO1C was ubiquitously expressed in all human tissues examined, in contrast to other known coronin-like molecules, each of which is expressed in a tissue-specific manner. Immunocytochemical staining demonstrated that CORO1C was co-localized with F-actin; therefore, the gene product is likely to be important in cytokinesis, motility, and signal transduction, as are the other members of this molecular family. We assigned this novel gene to chromosome 12q24.1 by fluorescence in situ hybridization.

Study of the Mechanism of Invasion and Metastasis in Pancreatic Cancer. Analysis of Cancer Cell Dissociation Factor.

膵臓癌の転移機構を明らかにする目的で, BOP誘導実験膵癌組織から樹立した高転移株 (PC-1・0) 培養上清中に存在する癌細胞解離因子 (DF) 分離精製し, その本態と膵癌の浸潤転移機構との関連について解析を行った. DFの精製を進め構成アミノ酸解析を行った結果, DFは新しいタイプのmetalloproteaseあるいはムチン様の構造をもつFc binding proteinであることが示唆された. 生物学的活性を解析した結果, DFには癌細胞コロニーを濃度依存的に解離し, 細胞運動能を増強させ, さらに, fibronectinに対する接着能を選択的に増強し, MATRIBGELに対する細胞浸潤能を増強する作用が存在した. 本研究の結果から, DFは膵臓癌の浸潤転移機構と密接に関連した生物学的特性を有する新しい因子であることが示唆された.