RIPA buffer with 500 mM NaCl, clarified, and protein normalized by bicinchoninic
acid assay (Pierce). Proteins (20–30 μg) were resolved by
7.5% or 10% SDS-PAGE, transferred to a polyvinylidene fluoride
membrane and blocked with Odyssey Block (LI-COR Biosciences). Blots were probed
for Cyclin D3 (DCS22, 1:1000) or JAK3 (D7B12, 1:1000) (Cell Signaling
Technologies), normalized to tubulin (DM1A, 1:5000, Sigma-Aldrich) and detected
with fluorescent secondary antibodies on an Odyssey Scanner (LI-COR
Biosciences). Alternatively, blots were probed with HRP-linked goat-anti-rabbit
secondary (Southern Biotech, Birmingham AL), developed with Western Lightening
Plus ECL (Pierce) and detected on a ChemiDocMP (Biorad).