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6d4g

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N-GTPase domain of p190RhoGAP-A

Structural highlights

6d4g is a 2 chain structure with sequence from Rattus norvegicus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.8Å
Ligands:	,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

RHG35_RAT Represses transcription of the glucocorticoid receptor by binding to the cis-acting regulatory sequence 5'-GAGAAAAGAAACTGGAGAAACTC-3'. May transduce signals from p21-ras to the nucleus, acting via the ras GTPase-activating protein (GAP). May also act as a tumor suppressor (By similarity).

Publication Abstract from PubMed

The pseudoGTPases are a rapidly growing and important group of pseudoenzymes. p190RhoGAP proteins are critical regulators of Rho signaling and contain two previously identified pseudoGTPase domains. Here we report that p190RhoGAP proteins contain a third pseudoGTPase domain, termed N-GTPase. We find that GTP constitutively purifies with the N-GTPase domain, and a 2.8-A crystal structure of p190RhoGAP-A co-purified with GTP reveals an unusual GTP-Mg(2+) binding pocket. Six inserts in N-GTPase indicate perturbed catalytic activity and inability to bind to canonical GTPase activating proteins, guanine nucleotide exchange factors, and effector proteins. Biochemical analysis shows that N-GTPase does not detectably hydrolyze GTP, and exchanges nucleotide only under harsh Mg(2+) chelation. Furthermore, mutational analysis shows that GTP and Mg(2+) binding stabilizes the domain. Therefore, our results support that N-GTPase is a nucleotide binding, non-hydrolyzing, pseudoGTPase domain that may act as a protein-protein interaction domain. Thus, unique among known proteins, p190RhoGAPs contain three pseudoGTPase domains.

The N-Terminal GTPase Domain of p190RhoGAP Proteins Is a PseudoGTPase.,Stiegler AL, Boggon TJ Structure. 2018 Aug 16. pii: S0969-2126(18)30261-2. doi:, 10.1016/j.str.2018.07.015. PMID:30174148^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Stiegler AL, Boggon TJ. The N-Terminal GTPase Domain of p190RhoGAP Proteins Is a PseudoGTPase. Structure. 2018 Aug 16. pii: S0969-2126(18)30261-2. doi:, 10.1016/j.str.2018.07.015. PMID:30174148 doi:http://dx.doi.org/10.1016/j.str.2018.07.015