Association of high-molecular-weight proteins with microtubules and their role in microtubule assembly in vitro.
- 1 July 1975
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 72 (7), 2696-2700
- https://doi.org/10.1073/pnas.72.7.2696
Abstract
High-molecular-weight components (HMW) specifically associated with microtubule protein purified from porcine brain tissue were separated from tubulin by DEAE-Sephadex ion exchange chromatography. Analysis by viscometry, sedimentation, and electron microscopy of the unfractionated microtubule protein, separated HMW and tubulin fractions, and reconstituted mixtures showed that HMW promoted formation of ring structures at 5 degrees and tubule polymerization at 37 degrees. The HMW reassociated with tubulin and was identified in thin sections as 18.9 x 5.6 nm projections attached to the microtubules with a longitudinal periodicity of 32.5 nm. These studies: (1) indicate that the HMW fraction stimulates microtubule assembly by facilitating the formation of ring structures which are apparently intermediates in polymerization, and (2) demonstrate that the HMW associates with microtubules as a structural component projecting from the surface of the microtubule wall.Keywords
This publication has 23 references indexed in Scilit:
- Ultrastructural localization of the high molecular weight proteins associated with in vitro-assembled brain microtubulesThe Journal of cell biology, 1975
- MICROTUBULAR ORGANIZATION IN ELONGATING MYOGENIC CELLSThe Journal of cell biology, 1974
- Directionality of Brain Microtubule Assembly In VitroProceedings of the National Academy of Sciences, 1974
- A dynein‐like protein from brainFEBS Letters, 1974
- Microtubules from Mammalian Brain: Some Properties of Their Depolymerization Products and a Proposed Mechanism of Assembly and DisassemblyProceedings of the National Academy of Sciences, 1974
- Microtubule assembly in vitro.1974
- Assembly of microtubules from preformed, ring‐shaped protofilaments and 6‐s tubulinJournal of Supramolecular Structure, 1974
- The in vitro polymerization of tubulin from beef brainJournal of Neurobiology, 1974
- The effect of partial extraction of dynein arms on the movement of reactivated sea-urchin spermJournal of Cell Science, 1973
- PROTEIN MEASUREMENT WITH THE FOLIN PHENOL REAGENTJournal of Biological Chemistry, 1951