This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2fju
From Proteopedia
Activated Rac1 bound to its effector phospholipase C beta 2
Contents |
Overview
Although diverse signaling cascades require the coordinated regulation of heterotrimeric G proteins and small GTPases, these connections remain poorly understood. We present the crystal structure of the GTPase Rac1 bound to phospholipase C-beta2 (PLC-beta2), a classic effector of heterotrimeric G proteins. Rac1 engages the pleckstrin-homology (PH) domain of PLC-beta2 to optimize its orientation for substrate membranes. Gbetagamma also engages the PH domain to activate PLC-beta2, and these two activation events are compatible, leading to additive stimulation of phospholipase activity. In contrast to PLC-delta, the PH domain of PLC-beta2 cannot bind phosphoinositides, eliminating this mode of regulation. The structure of the Rac1-PLC-beta2 complex reveals determinants that dictate selectivity of PLC-beta isozymes for Rac GTPases over other Rho-family GTPases, and substitutions within PLC-beta2 abrogate its stimulation by Rac1 but not by Gbetagamma, allowing for functional dissection of this integral signaling node.
Disease
Known disease associated with this structure: Platelet PLC beta-2 deficiency OMIM:[604114]
About this Structure
2FJU is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of Rac1 bound to its effector phospholipase C-beta2., Jezyk MR, Snyder JT, Gershberg S, Worthylake DK, Harden TK, Sondek J, Nat Struct Mol Biol. 2006 Dec;13(12):1135-40. Epub 2006 Nov 19. PMID:17115053 Page seeded by OCA on Sun May 4 03:58:56 2008
