Crystal structure of an active form of RAS protein, a complex of a GTP analog and the HRAS p21 catalytic domain.

AUTOR(ES)

Brünger, A T

RESUMO

Normal RAS proteins play a key role of molecular switch in the transduction of the growth signal from extracellular to intracellular space. The state of the switch is "on" when GTP is bound and "off" when GDP is bound to the protein. The crystal structure of a complex between a nonhydrolyzable GTP analog and the catalytic domain of a RAS protein has been determined by a rotation-translation search method. The orientations and positions of four independent molecules have been determined using a single molecule as a probe in the search. The crystal structure reveals that the gamma phosphate of the GTP analog induces extensive conformational changes on two loop regions of the protein.

Documentos Relacionados

• A stimulatory GDP/GTP exchange protein for smg p21 is active on the post-translationally processed form of c-Ki-ras p21 and rhoA p21.
• Refined crystal structure of the triphosphate conformation of H-ras p21 at 1.35 A resolution: implications for the mechanism of GTP hydrolysis.
• Structural significance of the GTP-binding domain of ras p21 studied by site-directed mutagenesis.
• Biochemical and crystallographic characterization of a complex of c-Ha-ras p21 and caged GTP with flash photolysis.
• Photoaffinity labeling with GTP of viral p21 ras protein expressed in Escherichia coli.