Centriole length control

•Centriolar microtubule regulators can be classified into ‘centriole length activators’ (CEAs) and ‘centriole length inhibitors’ (CEIs).•CEAs and CEIs form interaction networks together with their accessory proteins.•The crosstalk between the CEA and CEI networks may control centriole length. Centrioles are microtubule-based structures involved in cell division and ciliogenesis. Centriole formation is a highly regulated cellular process and aberrations in centriole structure, size or numbers have implications in multiple human pathologies. In this review, we propose that the proteins that control centriole length can be subdivided into two classes based on their antagonistic activities on centriolar microtubules, which we refer to as ‘centriole elongation activators’ (CEAs) and ‘centriole elongation inhibitors’ (CEIs). We discuss and illustrate the structure-function relationship of CEAs and CEIs as well as their interaction networks. Based on our current knowledge, we formulate some outstanding open questions in the field and present possible routes for future studies.