supporting stem, which suggests that only the structural stability of the cre is important. assembly and organization of the picornavirus vpg ribonucleoprotein complex two 3cd (vpg complex) molecules bind to cre with the 3c domains (vpg domain) contacting the upper stem and the 3d domains (vpg domain) contacting the lower stem. the 3c dimer opens the rna stem by forming a more stable interaction with single strands forming the stem. 3dpol is recruited to and retained in this complex by a physical interaction between the back-of-the-thumb subdomain of 3dpol and a surface of one or both 3c subdomains of 3cd. vpg may also play an important role in specific recognition of viral genome by movement proteins (mp), which are nonstructural proteins encoded by many, if not all, plant viruses to enable their movement from one infected cell to neighboring cells. mp and vpg interact to provide specificity for the transport of viral rna from cell to cell. to fulfill energy requirements, mp also interacts with p10, which is a cellular atpase. diseases picornaviruses cause a range of diseases. enteroviruses of the picornavirus family infect the enteric tract, which is reflected in their name. rhinoviruses infect primarily the nose and the throat. enteroviruses replicate at 37 °c, whereas rhinoviruses grow better at 33 °c, as this is the lower temperature of the nose. enteroviruses are stable under acidic conditions, thus they are able to survive exposure to gastric acid. in contrast, rhinoviruses are acid-labile (inactivated or destroyed by low ph conditions), so rhinovirus infections are restricted to the nose and throat. taxonomy these genera are recognized: aalivirus ailurivirus ampivirus anativirus aphthovirus aquamavirus avihepatovirus avisivirus boosepivirus bopivirus caecilivirus cardiovirus cosavirus crahelivirus crohivirus danipivirus dicipivirus diresapivirus enterovirus erbovirus felipivirus fipivirus gallivirus gruhelivirus grusopivirus harkavirus hemipivirus hepatovirus hunnivirus kobuvirus kunsagivirus limnipivirus livupivirus ludopivirus malagasivirus marsupivirus megrivirus mischivirus mosavirus mupivirus myrropivirus orivirus oscivirus parabovirus parechovirus pasivirus passerivirus pemapivirus poecivirus potamipivirus pygoscepivirus rabovirus rafivirus rajidapivirus rohelivirus rosavirus sakobuvirus salivirus sapelovirus senecavirus shanbavirus sicinivirus symapivirus teschovirus torchivirus tottorivirus tremovirus tropivirus