Endocytosis of integrin-binding human picornaviruses

: Pirjo Merilahti, Satu Koskinen, Outi Heikkila, Eveliina Karelehto, Petri Susi

Publisher: Hndawi Publishing

: 2012

: Advances in Virology

: 1687-8639

DOI: https://doi.org/10.1155/2012/547530

Picornaviruses that infect humans form one of the largest virus groups with almost three hundred virus types. They include
significant enteroviral pathogens such as rhino-, polio-, echo-, and coxsackieviruses and human parechoviruses that cause wide
range of disease symptoms. Despite the economic importance of picornaviruses, there are no antivirals. More than ten cellular
receptors are known to participate in picornavirus infection, but experimental evidence of their role in cellular infection has
been shown for only about twenty picornavirus types. Three enterovirus types and one parechovirus have experimentally been
shown to bind and use integrin receptors in cellular infection. These include coxsackievirus A9 (CV-A9), echovirus 9, and human
parechovirus 1 that are among the most common and epidemic human picornaviruses and bind to áV-integrins via RGD motif
that resides on virus capsid. In contrast, echovirus 1 (E-1) has no RGD and uses integrin á2â1 as cellular receptor. Endocytosis
of CV-A9 has recently been shown to occur via a novel Arf6- and dynamin-dependent pathways, while, contrary to collagen
binding, E-1 binds inactive â1 integrin and enters via macropinocytosis. In this paper, we review what is known about receptors
and endocytosis of integrin-binding human picornaviruses.