Abstract:
:The intravascular trematode Schistosoma mansoni is a causative agent of schistosomiasis, a disease that constitutes a major health problem globally. In this study we cloned and characterized the schistosome tegumental phosphodiesterase SmNPP-5 and evaluated its role in parasite virulence. SmNPP-5 is a 52.5-kDa protein whose gene is rapidly turned on in the intravascular parasitic life stages, following invasion of the definitive host. Highest expression is found in mated adult males. As revealed by immunofluorescence analysis, SmNPP-5 protein is found prominently in the dorsal surface of the tegument of males. Localization by immuno-electron microscopy illustrates a unique pattern of immunogold-labeled SmNPP-5 within the tegument; some immunogold particles are scattered throughout the tissue, but many are clustered in tight arrays. To determine the importance of the protein for the parasites, RNA interference (RNAi) was employed to knock down expression of the SmNPP-5-encoding gene in schistosomula and adult worms. Both quantitative real-time PCR (qRT-PCR) and Western blotting confirmed successful and robust gene suppression. In addition, the suppression and the ectolocalization of this enzyme in live parasites were evident because of a significantly impaired ability of the suppressed parasites to hydrolyze exogenously added phosphodiesterase substrate p-nitrophenyl 5'-dTMP (p-Nph-5'-TMP). The effects of suppressing expression of the SmNPP-5 gene in vivo were tested by injecting parasites into mice. It was found that, unlike controls, parasites whose SmNPP-5 gene was demonstrably suppressed at the time of host infection were greatly impaired in their ability to establish infection. These results demonstrate that SmNPP-5 is a virulence factor for schistosomes.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Bhardwaj R,Krautz-Peterson G,Da'dara A,Tzipori S,Skelly PJdoi
10.1128/IAI.05431-11subject
Has Abstractpub_date
2011-10-01 00:00:00pages
4276-84issue
10eissn
0019-9567issn
1098-5522pii
IAI.05431-11journal_volume
79pub_type
杂志文章abstract::The stimulation of mononuclear phagocytes by lipopolysaccharide (LPS) is facilitated by the binding of complexes of LPS and LPS-binding protein to CD14. Although it is clear that CD14 is involved in LPS-induced signaling, other investigators have hypothesized the existence of additional signaling pathways in macrophag...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.10.4452-4461.1993
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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doi:10.1128/IAI.06339-11
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.3.4.574-579.1971
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.10.7047-7050.2005
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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doi:10.1128/iai.68.2.577-583.2000
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.52.3.818-822.1986
更新日期:1986-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.46.1.116-121.1984
更新日期:1984-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.49.2.270-274.1985
更新日期:1985-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3550-3554.1995
更新日期:1995-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00513-10
更新日期:2010-12-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.00196-06
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journal_title:Infection and immunity
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.54.3.761-767.1986
更新日期:1986-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.8.3033-3041.1992
更新日期:1992-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.4.1593-1595.1993
更新日期:1993-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.50.1.304-309.1985
更新日期:1985-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:1994-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.11.6311-6320.2000
更新日期:2000-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.3.634-638.1977
更新日期:1977-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.1.584-588.2004
更新日期:2004-01-01 00:00:00