5XC7

Dengue Virus 4 NS3 Helicase D290A mutant

5XC7 の概要

• エントリーDOI: 10.2210/pdb5xc7/pdb
• 関連するPDBエントリー: 5XC6
• 分子名称: NS3 Helicase, GLYCEROL, CHLORIDE ION, ... (4 entities in total)
• 機能のキーワード: helicase, dengue ns3, hydrolase
• 由来する生物種: Dengue virus 4
• 細胞内の位置: Host endoplasmic reticulum membrane ; Peripheral membrane protein ; Lumenal side . Host nucleus . Secreted . Virion membrane ; Multi-pass membrane protein : M9P7S0
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 51541.16

構造登録者

Swarbrick, C.M.D.,Basavannacharya, C.,Chan, K.W.K.,Chan, S.A.,Singh, D.,Wei, N.,Phoo, W.W.,Luo, D.,Lescar, J.,Vasudevan, S.G. (登録日: 2017-03-22, 公開日: 2017-11-08, 最終更新日: 2023-11-22)

主引用文献

Swarbrick, C.M.D.,Basavannacharya, C.,Chan, K.W.K.,Chan, S.A.,Singh, D.,Wei, N.,Phoo, W.W.,Luo, D.,Lescar, J.,Vasudevan, S.G.
NS3 helicase from dengue virus specifically recognizes viral RNA sequence to ensure optimal replication
Nucleic Acids Res., 45:12904-12920, 2017

PubMed Abstract: The protein-RNA interactions within the flavivirus replication complex (RC) are not fully understood. Our structure of dengue virus NS3 adenosine triphosphatase (ATPase)/helicase bound to the conserved 5' genomic RNA 5'-AGUUGUUAGUCU-3' reveals that D290 and R538 make specific interactions with G2 and G5 bases respectively. We show that single-stranded 12-mer RNA stimulates ATPase activity of NS3, however the presence of G2 and G5 leads to significantly higher activation. D290 is adjacent to the DEXH motif found in SF2 helicases like NS3 and interacts with R387, forming a molecular switch that activates the ATPase site upon RNA binding. Our structure guided mutagenesis revealed that disruption of D290-R387 interaction increases basal ATPase activity presumably as a result of higher conformational flexibility of the ATPase active site. Mutational studies also showed R538 plays a critical role in RNA interactions affecting translocation of viral RNA through dynamic interactions with bases at positions 4 and 5 of the ssRNA. Restriction of backbone flexibility around R538 through mutation of G540 to proline abolishes virus replication, indicating conformational flexibility around residue R538 is necessary for RNA translocation. The functionally critical sequence-specific contacts in NS3 RNA binding groove in subdomain III reveals potentially novel allosteric anti-viral drug targets.

PubMed: 29165589
DOI: 10.1093/nar/gkx1127

実験手法

X-RAY DIFFRACTION (2.1 Å)