CYLD does not regulate RIP1 ubiquitination within the TNFR1 complex.

<p>(<b>A</b>) Recruitment of CYLD and A20 to the TNFR-1 complex. TNFR1 complex was purified from TNF, zVAD and CHX treated cells by immunoprecipitation (IP). The recruitment of RIP1, CYLD and A20 was assessed via Western Blot. Control IPs with isotype-matched IgG were included to show the specificity of binding to TNFR-1. (<b>B</b>) CYLD^+/+ and CYLD^-/- MEFs were treated with TNF for the indicated times. Recruitment of polyubiquitinated RIP1 to TNFR-1 was determined by Western Blot. (<b>C</b>) IκBα phosphorylation and degradation was normal in CYLD^-/- MEFs.