SprD explained

SprD
Symbol:	SprD
Rfam:	RF01828
Rna Type:	Gene
Tax Domain:	Staphylococcus aureus

In molecular biology SprD (Small pathogenicity island RNA D) is a non-coding RNA expressed on pathogenicity islands in Staphylococcus aureus.^[1] It was identified in silico along with a number of other sRNAs (SprA-G) through microarray analysis which were confirmed using a Northern blot.^[2] SprD has been found to significantly contribute to causing disease in an animal model.

Function

SprD is located between genes scn and chp in the innate immune evasion cluster (IEC) of the S. aureus genome. Its placement within this region was the first indication of a virulence-factor regulatory function.

SprD binds with sbi (Staphylococcus aureus binder of IgG)^[3] mRNA which encodes an immune evasion protein. It occludes the Shine-Dalgarno sequence and the initiation codon of sbi, forming a sbi mRNA-SprD duplex repressing the translation of the mRNA.

sbi protein interferes with the host's innate immune response by binding Factor H, Complement component 3 and IgG.^[4]

See also

• Protein A
• SprX

Further reading

• Upadhyay A, Burman JD, Clark EA, etal . Structure-function analysis of the C3 binding region of Staphylococcus aureus immune subversion protein Sbi . J. Biol. Chem. . 283 . 32 . 22113–22120 . August 2008 . 18550524 . 2494919 . 10.1074/jbc.M802636200 . free .
• Burman JD, Leung E, Atkins KL, etal . Interaction of human complement with Sbi, a staphylococcal immunoglobulin-binding protein: indications of a novel mechanism of complement evasion by Staphylococcus aureus . J. Biol. Chem. . 283 . 25 . 17579–17593 . June 2008 . 18434316 . 2649420 . 10.1074/jbc.M800265200 . free .
• Atkins KL, Burman JD, Chamberlain ES, etal . S. aureus IgG-binding proteins SpA and Sbi: host specificity and mechanisms of immune complex formation . Mol. Immunol. . 45 . 6 . 1600–1611 . March 2008 . 18061675 . 10.1016/j.molimm.2007.10.021 .
• Chabelskaya S, Bordeau V, Felden B . Dual RNA regulatory control of a Staphylococcus aureus virulence factor . Nucleic Acids Research. Apr 1, 2014. 42. 8. 4847–4858. 24510101. 10.1093/nar/gku119. 4005698.

Notes and References

1. Chabelskaya S, Gaillot O, Felden B . A Staphylococcus aureus small RNA is required for bacterial virulence and regulates the expression of an immune-evasion molecule . PLOS Pathog. . 6 . 6 . e1000927 . June 2010 . 20532214 . 2880579 . 10.1371/journal.ppat.1000927 . free .
2. Pichon C, Felden B . Small RNA genes expressed from Staphylococcus aureus genomic and pathogenicity islands with specific expression among pathogenic strains . Proc. Natl. Acad. Sci. U.S.A. . 102 . 40 . 14249–14254 . October 2005 . 16183745 . 1242290 . 10.1073/pnas.0503838102 . free .
3. Haupt K, Reuter M, van den Elsen J, etal . The Staphylococcus aureus protein Sbi acts as a complement inhibitor and forms a tripartite complex with host complement Factor H and C3b . PLOS Pathog. . 4 . 12 . e1000250 . December 2008 . 19112495 . 2602735 . 10.1371/journal.ppat.1000250 . free .
4. Zhang L, Jacobsson K, Vasi J, Lindberg M, Frykberg L . A second IgG-binding protein in Staphylococcus aureus . Microbiology . 144 . 4. 985–991 . April 1998 . 9579072 . 10.1099/00221287-144-4-985. 2010-08-09. free .