pCav-1 wt (myc-tagged canine Cav-1 cDNA in pCIS2) and pCav-1 SD (point mutations F92A V94A in scaffolding domain) are described elsewhere [21] . pM2PR8-EGFP and pM2PR8-dsRED were constructed by PCRcloning of M2 (A/PR/8/34/(H1/N1) into BamHI/AgeI linearized pEGFP-N1 and pDsRed-Express-N1 (Clontech), respectively. M2 identity was verified by DNA sequencing. pEP24c (M2 cDNA) [29] . pRVH1-Puro-Cav-1 and pRVH1-Puro [20] are described elsewhere.