Home
Database
Research
About us
G6-16 aptamer
Timeline
An aptamer called 10G-1, which binds specifically to the NS3 protease, was selected for the first time by in vitro genetic-selection strategy[1]
Keigo Machida et al. isolated aptamers that inhibited the activity of NS3 protease and helicase[2]
Kotaro Fukuda et al. isolated RNA aptamers that bind specifically to the NS3 protease active site in the truncated polypeptide ΔNS3[3]
The binding sites of NS3 protease domain and aptamer were analyzed by alanine scanning mutagenesis[4]
Fumiko Nishikawa et al. constructed a G9 aptamer expression system in cultured cells, using the cytomegarovirus enhancer + chicken beta-actin globin (CAG) promoter[5]
Byounghoon Hwang et al. isolated specific RNA aptamers to the helicase domain of HCV NS3 from a combinatorial RNA library with 40-nucleotide random sequences using in vitro selection techniques[6]
Kotaro Fukuda et al. designed a new aptamer called NEO-III-14U to inhibit both protease and helicase activity[7]
Robert Vaughan et al. showed that RNAs can bind directly to the active site cleft of the NS3 protease domain (NS3P) and inhibit proteolysis of peptide substrates. RNAs that are less apt to form intramolecular structures have a stronger inhibitory activity than RNAs with more stable base paired regions[8]
Description
In 1997, Keigo Machida and colleagues used an in vitro genetic-selection strategy to isolate high affinity RNA aptamers that bind to the NS3 protein. These aptamers can effectively inhibit the activities of NS3 protease and helicase[2].SELEX
In 1997, Keigo Machida and colleagues designed a selecting method based on existing research. They used a genetic selection strategy in vitro to isolate, from a pool of completely random RNA (120 random bases), those RNA aptamers that could bind to NS3. After six cycles of selection and amplification, 14% of the pooled RNAs could bind specifically to the NS3 protein. When the aptamers in the pool (cycle 6) were analyzed for binding and inhibition of the proteolytic activity of NS3 with the NS5A/NS5B peptide as substrate (S1), two aptamers, designated G6-16 and G6-19 RNA, were found to inhibit NS3 in vitro[2].
Detailed information are accessible on SELEX page.
Structure
G6-16 was the aptamer sequence mainly studied in the article, which had a high affinity with HCV NS3 protein. The 2D structure of the figure is based on the article by ribodraw tool to draw[2].5'-GGGAGAAUUCCGACCAGAAGGCUUGCUGUUGUUUCCCUGUUGUUUUGUCUCUCAACUUUAUUGUGGUAAAGAUCACUGGGUUGAUAAGGGCUAACUCUAAUUUGACUACAUGGUCGGACCAAUCAGUUCUUAUGGGAGAUGCAUAUGUGCGUCUACAUGGAUCCUCA-3'
Ligand information
SELEX ligand
Hepatitis C virus NS3 protein is a serine protease which has a trypsin-like fold. The non-structural (NS) protein NS3 is one of the NS proteins involved in replication of the HCV genome. The action of NS3 protease (NS3P), which resides in the N-terminal one-third of the NS3 protein, then yields all remaining non-structural proteins.-----From Pfam| Name | Uniprot ID | Pfam | MW | Amino acids sequences | PDB | Gene ID |
|---|---|---|---|---|---|---|
| HCV NS3 protease | B2Y2M9 | PF02907 | 19.15 kDa | APITAYAQQTRGLLGCIITSLTGRDKNQVEGEVQIVSTATQTFLATCINGVCWTVYHGAGTRTIASPKGPVIQMYTNVDQDLVGWPAPQGSRSLTPCTCGSSDLYLVTRHADVIPVRRRGDSRGSLLSPRPISYLKGSSGGPLLCPAGHAVGLFRAAVCTRGVAKAVDFIPVENLETTMRS | 3KF2 | ABY67662.1 |
| Name | Sequence | Ligand | Affinity |
|---|---|---|---|
| G6-16 | GGGAGAAUUCCGACCAGAAGGCUUGCUGUUGUUUCCCUGUUGUUUUGUCUCUCAACUUUAUUGUGGUAAAGAUCACUGGGUUGAUAAGGGCUAACUCUAAUUUGACUACAUGGUCGGACCAAUCAGUUCUUAUGGGAGAUGCAUAUGUGCGUCUACAUGGAUCCUCA | HCV NS3 protein | 120 ± 18 nM |
| △G6-16 | GGGAGAAUUCCGACCAGAAGGCUUGCUGUUGUUUCCCUGUUGUUUUGUCUCUCAACUUUAUUGUGGUAAAGAUCACUGGGUUGAUAAGGGCUAACUCUAAUUUGACUACAUGG | HCV NS3 protein | 238 ± 110 nM |
| G6-19 | GGGAGAAUUCCGACCAGAAGCUUAUACUGAAUUAAUCGCUACCGUGUCAUUGUACUUGGUAGUGUUGAUGGUUUGGGUCGCAUUUGGCUUGGCUUAUGGUUUUUUCACCCUACCUCUCAUUGACGCACUAGGCUCUCAUAUGUGCGUCUACAUGGAUCCUCA | HCV NS3 protein | NA |
Similar compound
We used the Dail server website to compare the structural similarities of ligand proteins, and chose the top 10 in terms of similarity for presentation. The Dali server is a network service for comparing protein structures in 3D. Dali compares them against those in the Protein Data Bank (PDB). Z-score is a standard score that is converted from an original score. The list of neighbours is sorted by Z-score. Similarities with a Z-score lower than 2 are spurious. RMSD (Root Mean Square Deviation) value is used to measure the degree to which atoms deviate from the alignment position.
| PDB | Z-socre | RMSD | Description |
|---|---|---|---|
| 1CU1-A | 20.7 | 1.0 | Protein (protease/helicase NS3) |
| 2W5E-A | 15.3 | 2.2 | Putative sering protease |
| 3K6Y-A | 14.7 | 2.7 | Possible membrane-associated sering protease |
| 2R3Y-A | 14.4 | 2.8 | Protease degs |
| 6Z05-A | 14.2 | 2.8 | Dego family sering endoprotease |
| 4INK-A | 13.4 | 2.8 | Sering protease spld |
| 5LKL-A | 13.3 | 3.0 | Genome polyprotein |
| 1SGP-E | 13.0 | 3.0 | Streptomyces griseus proteinase B |
| 7SJY-A | 12.8 | 3.1 | Anti-sigma-I factor RSGI9 |
| 8W20-C | 12.7 | 3.0 | Secreted protein |
References
[1] Selection of RNA aptamers that bind specifically to the NS3 protease of hepatitis C virus.Urvil, P. T., Kakiuchi, N., Zhou, D. M., Shimotohno, K., Kumar, P. K., & Nishikawa, S.
European journal of biochemistry, 248(1), 130–138. (1997)
[2] Isolation of RNA aptamers specific to the NS3 protein of hepatitis C virus from a pool of completely random RNA.
Kumar, P. K., Machida, K., Urvil, P. T., Kakiuchi, N., Vishnuvardhan, D., Shimotohno, K., Taira, K., & Nishikawa, S.
Virology, 237(2), 270–282. (1997)
[3] Isolation and characterization of RNA aptamers specific for the hepatitis C virus nonstructural protein 3 protease.
Fukuda, K., Vishnuvardhan, D., Sekiya, S., Hwang, J., Kakiuchi, N., Taira, K., Shimotohno, K., Kumar, P. K., & Nishikawa, S.
European journal of biochemistry, 267(12), 3685–3694. (2000)
[4] The RNA aptamer-binding site of hepatitis C virus NS3 protease.
Hwang, J., Fauzi, H., Fukuda, K., Sekiya, S., Kakiuchi, N., Shimotohno, K., Taira, K., Kusakabe, I., & Nishikawa, S.
Biochemical and biophysical research communications, 279(2), 557–562. (2000)
[5] Inhibition of HCV NS3 protease by RNA aptamers in cells.
Nishikawa, F., Kakiuchi, N., Funaji, K., Fukuda, K., Sekiya, S., & Nishikawa, S.
Nucleic acids research, 31(7), 1935–1943. (2003)
[6] Isolation of specific and high-affinity RNA aptamers against NS3 helicase domain of hepatitis C virus.
Hwang, B., Cho, J. S., Yeo, H. J., Kim, J. H., Chung, K. M., Han, K., Jang, S. K., & Lee, S. W.
RNA (New York, N.Y.), 10(8), 1277–1290. (2004)
[7] An RNA ligand inhibits hepatitis C virus NS3 protease and helicase activities.
Fukuda, K., Umehara, T., Sekiya, S., Kunio, K., Hasegawa, T., & Nishikawa, S.
Biochemical and biophysical research communications, 325(3), 670–675. (2004)
[8] RNA binding by the NS3 protease of the hepatitis C virus.
Vaughan, R., Li, Y., Fan, B., Ranjith-Kumar, C. T., & Kao, C. C.
Virus research, 169(1), 80–90. (2012)