|
|
| Line 1: |
Line 1: |
| <StructureSection load='1lgn' size='340' side='right' caption='Structure of human pentameric SAP (green, grey, pink, yellow, magenta) complex with AMP and Ca+2 ions (green) (PDB code [[1lgn]])' scene='87/875651/Cv/1'> | | <StructureSection load='4ht9' size='340' side='right' caption='Structure of human pentameric SAP (green, grey, pink, yellow, magenta) complex with AMP and Ca+2 ions (green) (PDB code [[4ht9]])' scene='87/875651/Cv/1'> |
|
| |
|
| == Function == | | == Function == |
|
| |
|
| '''Serum amyloid P-component''' (SAP) is a plasma protein and is the precursor of amyloid P-component which is constituent of deposits in amyloidosis and Alzheimer disease<ref>PMID:8202534</ref>. SAP binds in a calcium-dependent fashion to a variety of ligands. | | '''Protein Hfq''' (Hfq) ('''H'''ost '''F'''actor for '''Q'''β) or '''RNA-binding protein Hfq''' is stimulating base-pairing between sRNA and target mRNA by binding both RNAs via three RNA-binding surfaces. Hfq is found in enteric bacteria<ref>PMID:30487269</ref>. SAP binds in a calcium-dependent fashion to a variety of ligands. |
|
| |
|
| == Relevance == | | == Relevance == |
|
| |
|
| Mutations in SAP affect the aggregation of mutated lysozyme which cause amyloidosis. The inhibition of SAP binding to amyloid fibrils is a therapeutic target in some serious human diseases<ref>PMID:26176329</ref>. Small molecule ligands can displace SAP from amyloid fibrils and can provide therapeutic treatment of amyloidosis.
| | Since Hfq is required for gene regulation and infectivity of some Gram-negative bacteria its mutations can eliminate infectivity of Lyme disease caused by the bacteria ''Borellia burgdorferi,'' for example<ref>PMID:20815822</ref>. |
|
| |
|
| == Structural highlights == | | == Structural highlights == |
Revision as of 07:58, 22 February 2021
|
Function
Protein Hfq (Hfq) (Host Factor for Qβ) or RNA-binding protein Hfq is stimulating base-pairing between sRNA and target mRNA by binding both RNAs via three RNA-binding surfaces. Hfq is found in enteric bacteria[1]. SAP binds in a calcium-dependent fashion to a variety of ligands.
Relevance
Since Hfq is required for gene regulation and infectivity of some Gram-negative bacteria its mutations can eliminate infectivity of Lyme disease caused by the bacteria Borellia burgdorferi, for example[2].
Structural highlights
The 3D structure of a complex of SAP with the small molecule ligand AMP shows the nucleotide phosphate group bridging two Ca+2 ions and forming hydrogen bonds to Asn, Gln and Try residues of SAP [3].
- ↑ Morita T, Aiba H. Mechanism and physiological significance of autoregulation of the Escherichia coli hfq gene. RNA. 2019 Feb;25(2):264-276. doi: 10.1261/rna.068106.118. Epub 2018 Nov 28. PMID:30487269 doi:https://dx.doi.org/10.1261/rna.068106.118
- ↑ Lybecker MC, Abel CA, Feig AL, Samuels DS. Identification and function of the RNA chaperone Hfq in the Lyme disease spirochete Borrelia burgdorferi. Mol Microbiol. 2010 Nov;78(3):622-35. doi: 10.1111/j.1365-2958.2010.07374.x. Epub, 2010 Sep 27. PMID:20815822 doi:https://dx.doi.org/10.1111/j.1365-2958.2010.07374.x
- ↑ Hohenester E, Hutchinson WL, Pepys MB, Wood SP. Crystal structure of a decameric complex of human serum amyloid P component with bound dAMP. J Mol Biol. 1997 Jun 20;269(4):570-8. PMID:9217261 doi:10.1006/jmbi.1997.1075
|
3D Structures of protein Hfq
Updated on 22-February-2021
{"openlevels":0}
- Protein Hfq
- 1hk9, 2y90, 2yht, 3qhs, 4rcb, 4rcc, 6bdg – EcHfq – Escherichia coli
- 4jli, 4jri, 4jrk, 4juv – EcHfq (mutant)
- 1u1s, 1u1t, 4j6y, 6xyj – PaHfq – Pseudomonas aeruginosa
- 3inz, 3m4g, 4mml, 4mmk, 5i21 – PaHfq (mutant)
- 2ylb – StHfq – Salmonella typhimurium
- 6gwk – Hfq – Caulobacter crescentus
- 4nl2 – LmHfq – Listeria monocytogenes
- 4noy – LmHfq (mutant)
- 5szd – AaHfq – Aquifex aeolicus
- 3sb2 – Hfq - Herbaspirillum seropedicae
- 1kq1 – SaHfq – Staphylococcus aureus
- 2qtx, 4x9c – MjHfq – Methanococcus jannaschii
- 3hfn – Hfq - Anabaena
- Protein Hfq complex with nucleotide
- 3res – EcHfq + ADP
- 3qo3 – EcHfq + ATP
- 4pno – EcHfq + UMP
- 4j6x – PaHfq + UTP
- 3qui – PaHfq + ADPNP
- 4j5y – PaHfq + ATP
- 4j6w – PaHfq + CTP
- 2ylc – StHfq + UMP
- 5dy9 – MjHfq (mutant) + AMP
- 4x9d – MjHfq + UMP
- Protein Hfq other complexes
- 6qlb – EcHfq + calpain
- 3vu3 – EcHfq + catalase
- 3gib, 4ht8 – EcHfq + poly(A)
- 4ht9, 5new – EcHfq + poly(A) + poly(U)
- 3rer – EcHfq + poly(U) + ADP
- 4qvc, 4qvd – EcHfq + RNA
- 5uk7 – EcHfq + DNA
- 3ahu, 3hsb – Hfq + RNA – Bacillus subtilis
- 6o1k, 6o1l, 6o1m – PaHfq + Crc + RNA – Cryo EM
- 4v2s – StHfq + sRNA
- 4y91 – Hfq + poly(U) – Thermotoga maritima
- 4nl3 – LmHfq + poly(U)
- 5sze – AaHfq + poly(U)
- 1kq2 – SaHfq + RNA
References
