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Mouse Siglec-1 Mediates trans-Infection of Surface-bound Murine Leukemia Virus in a Sialic Acid N-Acyl Side Chain-dependent Manner.

ABSTRACT: Siglec-1 (sialoadhesin, CD169) is a surface receptor on human cells that mediates trans-enhancement of HIV-1 infection through recognition of sialic acid moieties in virus membrane gangliosides. Here, we demonstrate that mouse Siglec-1, expressed on the surface of primary macrophages in an interferon-?-responsive manner, captures murine leukemia virus (MLV) particles and mediates their transfer to proliferating lymphocytes. The MLV infection of primary B-cells was markedly more efficient than that of primary T-cells. The major structural protein of MLV particles, Gag, frequently co-localized with Siglec-1, and trans-infection, primarily of surface-bound MLV particles, efficiently occurred. To explore the role of sialic acid for MLV trans-infection at a submolecular level, we analyzed the potential of six sialic acid precursor analogs to modulate the sialylated ganglioside-dependent interaction of MLV particles with Siglec-1. Biosynthetically engineered sialic acids were detected in both the glycolipid and glycoprotein fractions of MLV producer cells. MLV released from cells carrying N-acyl-modified sialic acids displayed strikingly different capacities for Siglec-1-mediated capture and trans-infection; N-butanoyl, N-isobutanoyl, N-glycolyl, or N-pentanoyl side chain modifications resulted in up to 92 and 80% reduction of virus particle capture and trans-infection, respectively, whereas N-propanoyl or N-cyclopropylcarbamyl side chains had no effect. In agreement with these functional analyses, molecular modeling indicated reduced binding affinities for non-functional N-acyl modifications. Thus, Siglec-1 is a key receptor for macrophage/lymphocyte trans-infection of surface-bound virions, and the N-acyl side chain of sialic acid is a critical determinant for the Siglec-1/MLV interaction.

SUBMITTER: Erikson E

PROVIDER: S-EPMC4646371 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Mouse Siglec-1 Mediates trans-Infection of Surface-bound Murine Leukemia Virus in a Sialic Acid N-Acyl Side Chain-dependent Manner.

Erikson Elina E Wratil Paul R PR Frank Martin M Ambiel Ina I Pahnke Katharina K Pino Maria M Azadi Parastoo P Izquierdo-Useros Nuria N Martinez-Picado Javier J Meier Chris C Schnaar Ronald L RL Crocker Paul R PR Reutter Werner W Keppler Oliver T OT

The Journal of biological chemistry 20150914 45

Siglec-1 (sialoadhesin, CD169) is a surface receptor on human cells that mediates trans-enhancement of HIV-1 infection through recognition of sialic acid moieties in virus membrane gangliosides. Here, we demonstrate that mouse Siglec-1, expressed on the surface of primary macrophages in an interferon-α-responsive manner, captures murine leukemia virus (MLV) particles and mediates their transfer to proliferating lymphocytes. The MLV infection of primary B-cells was markedly more efficient than th ...[more]

PMID: 26370074

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Dataset Information

Mouse Siglec-1 Mediates trans-Infection of Surface-bound Murine Leukemia Virus in a Sialic Acid N-Acyl Side Chain-dependent Manner.

Publications

Mouse Siglec-1 Mediates trans-Infection of Surface-bound Murine Leukemia Virus in a Sialic Acid N-Acyl Side Chain-dependent Manner.

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