Characterization of purified proteins used in this study. (A) SDS-PAGE gel of GFP-CP110, CEP97-GFP, and CEP97^CP110-GFP, purified from HEK293T cells. Gels were stained with Coomassie brilliant blue R250. (B) Analysis of purified GFP-CP110, CEP97-GFP, and CEP97^CP110-GFP by mass spectrometry. (C) The proportion of fully blocked MTs with increasing concentrations of GFP-CP110 in in vitro reconstitution assays. n = 91, 28, 142, 105, and 140 MT plus ends for 5, 10, 20, 30, and 50 nM GFP-CP110. (D) A still image and a kymograph representing dynamic MT (blue) behavior in the presence of 50 nM CEP97-GFP (green, no binding). (E) Bar plot showing that CEP97-GFP does not affect the plus end blocking of dynamic MTs in vitro by GFP-CP110. The numbers of analyzed MTs are indicated on the bar plots. (F) SDS-PAGE of CPAP-N_WT-mCh and CPAP-N_MUT-mCh, purified from HEK293T cells. Gels were stained with Coomassie brilliant blue R250. (G) Analysis of purified CPAP-N_WT-mCh and CPAP-N_MUT-mCh by mass spectrometry. Source data are available for this figure: SourceData FS1.