Physarum Vitronectin-like Protein has Extensive Homology to Dihydrolipoamide Acetyltransferase

Cell Structure and Function

TOSHIYUKI MIYATA⁴  KOYOMI MIYAZAKI¹  MASAO HAYASHI¹  SADAYUKI MATUDA³  HAJIME SAWADA² 

[1] Department of Biology, Ochanomizu University;Department of Anatomy, School of Medicine, Yokohama City University;Department of Biology, Kanoya National Institute of Fitness and Sports;Laboratory of Thrombosis Research, National Cardiovascular Center Research Institute

关键词: cell-adhesive protein;    vitronectin;    Physarum;    dihydrolipoamide acetyltransferase;    protein chemistry;    immunocytochemistry;   

DOI  :  10.1247/csf.18.323

学科分类：分子生物学，细胞生物学和基因

来源: Japan Society for Cell Biology

【 摘 要 】

References(34)Physarum vitronectin-like protein with a molecular mass of 70 kDa cross-reacts with antibovine vitronectin and promotes cell-spreading (MIYAZAKI, K. et al. 1992. Exp. Cell Res., 199: 106-110.). The amino-terminal sequence of Physarum vitronectin-like protein is, however, distinct from those of animal vitronectins but shows significant sequence homology with dihydrolipoamide acetyltransferase, a component of pyruvate dehydrogenase complex. We have investigated the structural relationships between Physarum vitronectinlike protein and dihydrolipoamide acetyltransferase by using both antibody and protein-chemical methods. The vitronectin-like protein reacted with both anti-bovine vitronectin IgG and anti-rat pyruvate dehydrogenase complex IgG, indicating that it shares common antigenic determinant(s) with rat pyruvate dehydrogenase complex. Furthermore, sequencing studies of peptides obtained by lysylendopeptidase digestion indicated that internal sequences of Physarum vitronectin-like protein show significant homology with dihydrolipoamide acetyltransferase, but do not show any homology with the primary structures of authentic vitronectins. Immunocytochemistry revealed that the protein is widely localized in cytoplasm and nuclei of Physarum polycephalum, but is not present in the central area of vacuoles. Our results indicate that Physarum vitronectin-like protein is a molecule structurally and immunologically related to dihydrolipoamide acetyltransferase but functionally similar to animal vitronectin, although its localization is unique.

【 授权许可】

Unknown