Effects of Mutant Rat Dynamin on Endocytosis

• Published in: The Journal of cell biology 1993-08, Vol.122 (3), p.565-578
• Main Authors: Herskovits, Jonathan S., Burgess, Christopher C., Obar, Robert A., Vallee, Richard B.
• Format: Article
• Language: English
• Subjects: 3T3 cells; Adaptor Protein Complex alpha Subunits; Adaptor Proteins, Vesicular Transport; Amino Acid Sequence; Animals; Antibodies; Antibodies - immunology; Biological and medical sciences; Ca(2+) Mg(2+)-ATPase - chemistry; Ca(2+) Mg(2+)-ATPase - genetics; Ca(2+) Mg(2+)-ATPase - immunology; Ca(2+) Mg(2+)-ATPase - physiology; Cell Line; Cell physiology; Cells; Cellular biology; Clathrin - analysis; Clathrin - immunology; COS cells; Cultured cells; Deoxyribonucleic acid; DNA; Drosophila; Drosophila Proteins; Dynamins; Endocytosis; Fundamental and applied biological sciences. Psychology; Guanosine Triphosphate - metabolism; Microscopy, Fluorescence; Microtubules; Molecular and cellular biology; Molecular Sequence Data; Mutation; Neurons; Proteins - analysis; Proteins - immunology; Rats; Rodents; Transfection; Transferrins
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.122.3.565

Dynamin is a 100-kD microtubule-activated GTPase. Recent evidence has revealed a high degree of sequence homology with the product of the Drosophila gene shibire, mutations in which block the recycling of synaptic vesicles and, more generally, the formation of coated and non-coated vesicles at the plasma membrane. We have now transfected cultured mammalian COS-7 cells with both wild-type and mutant dynamin cDNAs. Point mutations in the GTP-binding consensus sequence elements of dynamin equivalent to dominant negative mutations in ras, and an NH2-terminal deletion of the entire GTP-binding domain of dynamin, block transferrin uptake and alter the distribution of clathrin heavy chain and α-, but not γ-, adaptin. COOH-terminal deletions reverse these effects, identifying this portion of dynamin as a site of interaction with other components of the endocytic pathway. Over-expression of neither wild-type nor mutant forms of dynamin affected the distribution of microtubules. These results demonstrate a specific role for dynamin and for GTP in the initial stages of receptor-mediated endocytosis.