Proteolytic processing is required for viral superantigen activity.

C G Park; M Y Jung; Y Choi; G M Winslow

doi:10.1084/jem.181.5.1899

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Proteolytic processing is required for viral superantigen activity.

C G Park·M Y Jung·Y Choi·G M Winslow

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Abstract

The mouse mammary tumor virus-7 superantigen (vSAG7) is proteolytically processed in B cells at as many as three positions. Proteolytic processing appears to be important for superantigen activity because a processed form of vSAG7 was predominant among those forms that were found to bind to major histocompatibility complex class II molecules. To determine the functional significance of proteolytic processing, a mutation was introduced in vSAG7 at one of the sites where proteolytic cleavage is thought to take place in B cells. Elimination of the putative processing site at position 171 abrogated detectable vSAG7 surface expression in B cells, indicating that proteolytic processing is required for vSAG7 function. Coexpression in insect cells of vSAG7 and furin, a proprotein-processing enzyme, also demonstrated that furin could process vSAG7 at position 171.

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Amino Acid Sequence Animals Antigen Presentation Antigens, Viral Base Sequence Furin Gammaretrovirus Molecular Sequence Data Spodoptera Subtilisins Superantigens Tumor Cells, Cultured Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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C G Park, M Y Jung, Y Choi, G M Winslow. 1995-05-01. Proteolytic processing is required for viral superantigen activity.. https://doi.org/10.1084/jem.181.5.1899

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