HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Caruso, M. Articles by Garcia, M.-I. Search for Related Content PubMed PubMed Citation Articles by Caruso, M. Articles by Garcia, M.-I. Agricola Articles by Caruso, M. Articles by Garcia, M.-I.

Role of sialic acid-containing molecules and the 41 integrin receptor in the early steps of polyomavirus infection

¹ Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Biotecnologie Cellulari ed Ematologia, Sezione di Genetica Molecolare, Università di Roma ‘La Sapienza’, Viale Regina Elena 324, 00161 Rome, Italy
² e Dipartimento di Medicina Sperimentale e Patologia, Sezione di Virologia, Università di Roma ‘La Sapienza’, Viale Regina Elena 324, 00161 Rome, Italy

Correspondence
Marie-Isabelle Garcia
garcia{at}bce.uniroma1.it
Paolo Amati
amati{at}bce.uniroma1.it

Murine polyomavirus (MPyV) infection occurs through recognition of sialic acid (SA) residues present on the host cell membrane, but the nature of the molecules involved and the exact role of this interaction in virus cell entry still need to be clarified. In this work, mutations at residues R⁷⁷ or H²⁹⁸ of the MPyV VP1 protein were shown to lead to a complete loss of virus infectivity, which, however, could be restored by lipofection of virus particles into the cytoplasm of the host cells. Using virus-like particles (VLPs), it was demonstrated that the non-infectivity of these mutants was due to impaired cell entry caused by total abrogation of SA-dependent cell binding. This indicates that SA residues are essential primary cell receptors for MPyV. As the 41 integrin has been identified recently as a cell receptor for MPyV, the relationship, if any, was investigated between SA-containing and 41 integrin receptors. The ability of mutants R⁷⁷Q and H²⁹⁸Q and wt VLPs to bind to cells overexpressing the 41 integrin was studied in SA-positive (BALB/c 3T3 cells and Pro-5 cells) and SA-deficient (Pro5-derived Lec-2 cells) backgrounds. Overexpression of 41 integrin did not restore binding of mutant VLPs in any of these cell lines or, indeed, that of wt VLPs in a SA-deficient background. Moreover, evidence is provided that overexpression of the sialylated 41 integrin enhances wt VLP cell binding, suggesting that, in addition to its function at a post-attachment level, 41 integrin acts also as one of the SA-containing receptors for initial cell binding.

M. Caruso and M. Cavaldesi contributed equally to this work.

This article has been cited by other articles:

				J. Gilbert and T. Benjamin Uptake Pathway of Polyomavirus via Ganglioside GD1a J. Virol., November 15, 2004; 78(22): 12259 - 12267. [Abstract] [Full Text] [PDF]

				M. Cavaldesi, M. Caruso, O. Sthandier, P. Amati, and M. I. Garcia Conformational Changes of Murine Polyomavirus Capsid Proteins Induced by Sialic Acid Binding J. Biol. Chem., October 1, 2004; 279(40): 41573 - 41579. [Abstract] [Full Text] [PDF]