Augmin complex activity finetunes dendrite morphology through non-centrosomal microtubule nucleation in vivo.

During development, neurons achieve a stereotyped neuron type-specific morphology, which relies on dynamic support by microtubules (MTs). An important player is the augmin complex (hereafter augmin), which binds to existing MT filaments and recruits the γ-tubulin ring complex (γ-TuRC), to form branched MTs. In cultured neurons, augmin is important for neurite formation.

Direct binding of CEP85 to STIL ensures robust PLK4 activation and efficient centriole assembly.

Centrosomes are required for faithful chromosome segregation during mitosis. They are composed of a centriole pair that recruits and organizes the microtubule-nucleating pericentriolar material. Centriole duplication is tightly controlled in vivo and aberrations in this process are associated with several human diseases, including cancer and microcephaly.

Proximity mapping of human separase by the BioID approach.

Separase is a caspase-like cysteine protease that is best known for its essential role during the metaphase-to-anaphase transition when it cleaves the cohesin ring complex that keeps the sister chromatids together. Another important function of separase is to regulate the process of centriole separation, known as centriole disengagement, at the end of mitosis. We used proximity-dependent biotin identification (BioID) to expand our knowledge on the identity of separase's proximity interactors.

Sensors at centrosomes reveal determinants of local separase activity.

Separase is best known for its function in sister chromatid separation at the metaphase-anaphase transition. It also has a role in centriole disengagement in late mitosis/G1. To gain insight into the activity of separase at centrosomes, we developed two separase activity sensors: mCherry-Scc1(142-467)-ΔNLS-eGFP-PACT and mCherry-kendrin(2059-2398)-eGFP-PACT.

Separate to operate: control of centrosome positioning and separation.

The centrosome is the main microtubule (MT)-organizing centre of animal cells. It consists of two centrioles and a multi-layered proteinaceous structure that surrounds the centrioles, the so-called pericentriolar material. Centrosomes promote de novo assembly of MTs and thus play important roles in Golgi organization, cell polarity, cell motility and the organization of the mitotic spindle.

Plk1 controls the Nek2A-PP1γ antagonism in centrosome disjunction.

In human cells, separation of the centrosomes and formation of a bipolar spindle are essential for correct chromosome segregation [1]. During interphase, centrosomes are joined together by the linker proteins C-Nap1 and rootletin [2-4]. At the onset of mitosis, these linker proteins are phosphorylated and displaced from centrosomes by the Nek2A kinase, which is regulated by two Hippo pathway components, Mst2 kinase and the scaffold protein hSav1.