Identification of Combover as the Drosophila ortholog of PCM1, related to Fig. 1,. (A) Related to Fig. 1 B. Conservation of PCM1, and core centriolar (STIL/ANA2, SASS6/SAS-6, CENPJ/SAS-4, CEP135/BLD10), centrosomal (CDK5RAP2/CNN, CEP192/SPD-2), and ciliary proteins (distal appendage, transition zone, IFT and BBS components, inner and outer dynein arm components, dynein assembly factors, nexins, N-DRC, radial spoke, and central apparatus components [Dobbelaere et al., 2023]) across opisthokonts, based on reciprocal BLAST analysis and hidden Markov model–based searches. Color code is green >2/3 of genes in indicated category present, yellow >1/3 of genes present, magenta <1/3 present. See also Table S1. (B) Results of LC-MS/MS analysis for direct BioID performed on the centriolar structural component SAS-4 in Drosophila S2 cells. Volcano plot of −log₁₀ P values against log₂ fold change (sample/control). Significantly enriched proteins (log₂ enrichment >1, P <0.05) are indicated in dark gray, with centrosomal proteins highlighted in magenta. CMB was detected as a high-confidence interactor. See also Table S2 A. (C) Related to Fig. 1 D. Further characterization of PCP phenotypes in the fly notum. RNAi of PCP genes such as Inturned results in strong phenotypes, while centrosomal genes (Sas-4 and Plp) show no or weak phenotypes. (D) Quantitation of bristle defects for selected genes. Phenotypes were scored on a scale from 0 (no phenotype) to 4 (strong phenotype), with values shifted slightly to avoid overlap. N = 10 flies per condition.