Phosphorylation of the centrosomal protein, Cep169, by Cdk1 promotes its dissociation from centrosomes in mitosis.

Cep169 is a centrosomal protein conserved among vertebrates. In our previous reports, we showed that mammalian Cep169 interacts and collaborates with CDK5RAP2 to regulate microtubule (MT) dynamics and stabilization. Although Cep169 is required for MT regulation, its precise cellular function remains largely elusive.

Cep169, a Novel Microtubule Plus-End-Tracking Centrosomal Protein, Binds to CDK5RAP2 and Regulates Microtubule Stability.

The centrosomal protein, CDK5RAP2, is a microcephaly protein that regulates centrosomal maturation by recruitment of a γ-tubulin ring complex (γ-TuRC) onto centrosomes. In this report, we identified a novel human centrosomal protein, Cep169, as a binding partner of CDK5RAP2, a member of microtubule plus-end-tracking proteins (+TIPs). Cep169 interacts directly with CDK5RAP2 through CM1, an evolutionarily conserved domain, and colocalizes at the pericentriolar matrix (PCM) around centrioles with CDK5RAP2.

Microtubule-bundling activity of the centrosomal protein, Cep169, and its binding to microtubules.

CDK5RAP2 is a centrosomal protein that regulates the recruitment of a γ-tubulin ring complex (γ-TuRC) onto centrosomes and microtubules (MTs) dynamics as a member of MT plus-end-tracking proteins (+TIPs). In our previous report, we found mammalian Cep169 as a CDK5RAP2 binding partner, and Cep169 accumulates at the distal ends of MTs and centrosomes, and coincides with CDK5RAP2. Depletion of Cep169 induces MT depolymerization, indicating that Cep169 targets MT tips and regulates stability and dynamics of MTs.

Determination of serum lipoprotein lipase using a latex particle-enhanced turbidimetric immunoassay with an automated analyzer.

Background: Lipoprotein lipase (LPL) plays a central role in triglyceride-rich lipoprotein metabolism by catalyzing the hydrolysis of triglycerides. Quantification of serum LPL is useful for diagnosing lipid disorders, but there is no rapid method of measuring LPL for clinical use.

Methods: We developed a rapid and sensitive latex particle-enhanced turbidimetric immunoassay (LTIA) serum LPL using latex bead-immobilized anti-LPL monoclonal antibodies.