Assembly of GMPCPP-bound tubulin into helical ribbons and tubes and effect of colchicine.
Microtubule assembly and disassembly is a complex structural process that does not proceed by simple addition and subtraction of individual subunits to and from a helical polymer, as would be the case for actin and other helical assemblies. The dynamic process of microtubule growth and shrinking involves short-lasting polymer forms that differ substantially from the microtubule itself and constitute crucial assembly and disassembly intermediates. Structural characterization thus depends on the stabilization of these brief intermediates and their preservation as polymeric assemblies. This paper gives experimental details on the polymerization of GMPCPP-tubulin into low-temperature, stable polymers that we propose to correspond to the early stages in microtubule assembly, and includes new data on the effect of colchicine on GMPCPP-tubulin polymerization. Finally, we add our thoughts on the possible biological meaning of tubulin polymerization versatility.
Wang
Hong-Wei
HW
Life Science Division, Lawrence Berkeley National Lab, Berkeley, California, USA. hwwang@lbl.gov
Long
Sydney
S
Finley
K Rose
KR
Nogales
Eva
E
D000818:Animals; D003078:Colchicine / Q000494:pharmacology*; D020285:Cryoelectron Microscopy; D006074:Gout Suppressants / Q000494:pharmacology; D006153:Guanosine Diphosphate / Q000737:chemistry; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives* / Q000737:chemistry; D007091:Image Processing, Computer-Assisted; D008869:Microtubule-Associated Proteins / Q000737:chemistry; D008870:Microtubules / Q000737:chemistry / Q000378:metabolism; D008954:Models, Biological; D011108:Polymers / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D017433:Protein Structure, Secondary; D013696:Temperature; D014404:Tubulin / Q000737:chemistry*
D006074:Gout Suppressants; D008869:Microtubule-Associated Proteins; D011108:Polymers; D014404:Tubulin; D006153:Guanosine Diphosphate; C004805:5'-guanylylmethylenebisphosphonate; D006160:Guanosine Triphosphate; D003078:Colchicine