A novel phosphoglucomutase-related protein is concentrated in adherens junctions of muscle and nonmuscle cells
| Autor: | Alexey M. Belkin, Victor E. Koteliansky, David R. Critchley, Matvey E. Lukashev, Kathryn Lilley, Irina V. Klimanskaya |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Adult
Vascular smooth muscle Phosphoglucomutase activity Blotting Western Molecular Sequence Data Cross Reactions Cell junction Muscle Smooth Vascular Adherens junction Fetus Pregnancy medicine Animals Humans Amino Acid Sequence Child Cytoskeleton Aorta Cells Cultured Actin Sequence Homology Amino Acid biology Muscles Uterus Antibodies Monoclonal Skeletal muscle Muscle Smooth Cell Biology Fibroblasts Molecular biology Peptide Fragments Molecular Weight Intercellular Junctions medicine.anatomical_structure Phosphoglucomutase Polyclonal antibodies biology.protein Electrophoresis Polyacrylamide Gel Female Rabbits |
| Zdroj: | Journal of Cell Science. 107:159-173 |
| ISSN: | 1477-9137 0021-9533 |
| DOI: | 10.1242/jcs.107.1.159 |
| Popis: | Using five monoclonal antibodies raised against a human uterine smooth muscle extract, we have identified a novel antigen which runs as a closely spaced doublet in SDS-gels. The proteins (60/63 kDa) co-purify, are present in a 1:1 ratio as judged by Coomassie Blue staining, and are immunologically closely related, if not identical. No N-terminal sequence could be obtained from a mixture of the 60/63 kDa proteins, but the sequence of four polypeptides liberated by V8 protease or cyanogen bromide cleavage showed that the proteins are closely related to the glycolytic enzyme phosphoglucomutase type 1. Affinity-purified polyclonal antibodies and three different monoclonal antibodies to the 60/63 kDa proteins cross-reacted with rabbit skeletal muscle phosphoglucomutase type 1, whilst two additional monoclonal antibodies were specific for the 60/63 kDa proteins. Peptide maps of the 60/63 kDa proteins and phosphoglucomutase 1 are markedly different, and the purified proteins have no detectable phosphoglucomutase activity. Staining of cultured smooth muscle cells and fibroblasts with antibodies to 60/63 kDa proteins showed that the antigen is concentrated in focal contacts at the ends of actin bundles and is also associated with actin filaments. About 60% of the cellular 60/63 kDa proteins were found in the detergent-insoluble fraction, suggesting a physical association with the cytoskeleton. The highest levels of protein immunoreactivity were found in muscles. The antigen is concentrated in muscle adherens junctions, including smooth muscle dense plaques, cardiomyocyte intercalated disks, and striated muscle myotendinous junctions. Among epithelial cells, the 63 kDa isoform of the protein was found only in cultured keratinocytes where immunofluorescent staining was localized in cell-to-cell adherens junctions. Expression of the 60/63 kDa proteins in vascular smooth muscle cells is developmentally regulated and correlates with the differentiated contractile phenotype of these cells. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|