(50mM Tris-HCl, pH 7.5, 137mM NaCl), and TBS. Beads were suspended in loading buffer (4% sodium dodecyl sulfate, 100mM dithiothreitol, 20% glycerol, 65mM Tris, pH 6.8, 0.005% bromophenol blue) and proteins were separated by SDS-poly acrylamide gel electrophoresis. Gels were transferred to a polyvinylidene difluoride membrane (Millipore, Bedford, MA), blocked with 5% BSA, washed, probed with primary Ab as indicated, followed by washing and incubation with protein A or G conjugated HRP (Pierce, Rockford, IL). Bands were detected with ECL reagents (Pierce, Rockford, IL) and imaged on the EpiChemi3 Darkroom (UVP Inc, Upland, CA). Supporting Information Figure S1 Endogenously expressed CAREx8 (A, D, G) in polarized human airway epithelia localizes above ZO-1 (B, C) and co-localizes with the apical protein ezrin (E, F, G). Sections are shown in X-Y (A-F) or X-Z (G) axes. Confocal microscopy (60x oil immersion). Found at: doi:10.1371/journal.pone.0009909.s001 (9.08 MB TIF) Figure S2 Quantitative RT-PCR primers for CAREx7 or CAREx8 are specific. Primary airway were either mock transduced or transduced with adenovirus carrying the gene for CAREx7 or CAREx8. RNA was isolated 36 hours later and subjected to isoform specific quantitative RT-PCR. Under mock References 1. Bergelson JM, Cunningham JA, Droguett G, Kurt-Jones EA, Krithivas A, et al. (1997) Isolation of a common receptor for coxsackie B viruses and adenoviruses 2 and 5. Science 275: 1320–1323. 2. Tomko RP, Xu R, Philipson L (1997) HCAR and MCAR: the human and mouse cellular receptors for subgroup C adenoviruses and group B coxsackieviruses. Proc Natl Acad Sci U S A 94: 3352–3356. 3. Honda T, Saitoh H, Masuko M, Katagiri-Abe T, Tominaga K, et al. (2000) The coxsackievirus-adenovirus receptor protein as a cell adhesion molecule in the developing mouse brain. Brain Res Mol Brain Res 77: 19–28. 4. 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