Two-dimensional and epitaxial crystallization of a mutant form of yeast RNA polymerase II.
A mutant form of yeast RNA polymerase II that lacks the fourth and seventh largest subunits, referred to as pol II delta 4/7, crystallized on positively charged lipid layers. Both single-layered (two-dimensional) crystals and several multi-layered crystal forms were obtained. The two-dimensional crystals, preserved in negative stain, diffracted strongly to about 1/20 A-1 and more weakly to 1/13 A-1 resolution. A projection map computed from averaged Fourier transforms revealed four pol II delta 4/7 complexes per unit cell and further revealed a cleft on the surface of the complex similar to that previously observed in the structure of Escherichia coli RNA polymerase. One of the multi-layered crystal forms, preserved in negative stain, diffracted strongly beyond 1/15 A-1 resolution. Coherent diffraction from the multi-layered crystal is indicative of protein-protein interactions between layers and ordering in the third dimension.
Department of Cell Biology, Beckman Laboratories, Fairchild Center, Stanford University, California 94305.
S A
SA
Darst
E W
EW
Kubalek
A M
AM
Edwards
R D
RD
Kornberg
D003460:Crystallization; D008854:Microscopy, Electron; D015903:Moire Topography; D009154:Mutation; D012319:RNA Polymerase II / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D014961:X-Ray Diffraction
D012319:RNA Polymerase II