The function of CSTPP1 (centriolar satellite-associated tubulin polyglutamylase complex regulator 1, Ensembl gene identifier ENSG00000149179) is as follows. Regulator of the tubulin polyglutamylase complex (TPGC) that controls cytoskeletal organization, nuclear shape, and cilium disassembly by balancing microtubule and actin assembly (PubMed:34782749). Regulates the assembly and stability of the TPGC and thereby modulates polyglutamylation of the microtubule, which antagonizes MAP4 binding (PubMed:34782749). .