microtubule-associated proteins ( maps ) and microtubules isolated from mitotic spindles which were mainly composed of a large amount of 75-kd protein and some high molecular mass ( 250 kd , 245 kd ) proteins were polymerized in vitro and examined by quick-freeze , deep-etch electron microscopy .
C0026045
microtubule-associated proteins
C0026046
microtubules