2LWD

Solution structure of second CARD of human RIG-I

Summary for 2LWD

• Entry DOI: 10.2210/pdb2lwd/pdb
• Related: 2LWE
• NMR Information: BMRB: 18622
• Descriptor: Probable ATP-dependent RNA helicase DDX58 (1 entity in total)
• Functional Keywords: rig-i, card, sensor, viral rna, helicase, signaling protein
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm: O95786
• Total number of polymer chains: 1
• Total formula weight: 11782.90

Authors

Dutta, K.,Ferrage, F.,Aggarwal, A. (deposition date: 2012-07-27, release date: 2012-10-31, Last modification date: 2024-05-01)

Primary citation

Ferrage, F.,Dutta, K.,Nistal-Villan, E.,Patel, J.R.,Sanchez-Aparicio, M.T.,De Ioannes, P.,Buku, A.,Aseguinolaza, G.G.,Garcia-Sastre, A.,Aggarwal, A.K.
Structure and Dynamics of the Second CARD of Human RIG-I Provide Mechanistic Insights into Regulation of RIG-I Activation.
Structure, 20:2048-2061, 2012

PubMed Abstract: RIG-I is a cytosolic sensor of viral RNA, comprised of two N-terminal CARDs followed by helicase and C-terminal regulatory domains (helicase-CTD). Viral RNA binds to the helicase-CTD and "exposes" the CARDs for downstream signaling. The role of the second CARD (CARD2) is essential as RIG-I activation requires dephosphorylation of Thr170 followed by ubiquitination at Lys172. Here, we present the solution structure and dynamics of human RIG-I CARD2. Surprisingly, we find that Thr170 is mostly buried. Parallel studies on the phosphomimetic T170E mutant suggest that the loss of function upon Thr170 phosphorylation is likely associated with changes in the CARD1-CARD2 interface that may prevent Lys172 ubiquitination and/or binding to free K63-linked polyubiquitin. We also demonstrate a strong interaction between CARD2 and the helicase-CTD, and show that mutations at the interface result in constitutive activation of RIG-I. Collectively, our data suggests a close interplay between phosphorylation, ubiquitination, and activation of human RIG-I, all mediated by CARD2.

PubMed: 23063562
DOI: 10.1016/j.str.2012.09.003

Experimental method

SOLUTION NMR