OLA1 in centrosome biology alongside the BRCA1/BARD1 complex: looking beyond centrosomes

Abstract

In this issue of Molecular Cell, Chiba and colleagues (Matsuzawa et al., 2014) identify Obg-like ATPase 1 (OLA1) as an additional member of the BRCA1/BARD1/γ-tubulin complex that is critically involved in centrosome amplification and microtubule aster formation.

Figure 1. Interactions within the OLA1/BRCA1/BARD1/γ-tubulin complex A

Primary structures of OLA1, BARD1and BRCA1 indicating functional domains. OLA1 interacts directly with the N-terminus of BRCA1 and the C-terminus of BARD1. BARD1 binds directly to the N-terminus of BRCA1 and the C-terminus of OLA1. BRCA1 associates directly with the N-terminus of BARD1. BRCA1 binding to OLA1 E168Q is impaired, suggesting that BRCA1 might bind in the ATPase domain of OLA1. γ-tubulin associates directly with the middle portion of BRCA1. RING, Really interesting new gene; ANK, ankyrin repeats; BRCT, BRCA1 carboxy terminal; CC, coiled-coil. B. Model illustrating the interactions within the complex. In addition to the direct interactions described above, OLA1 interacts indirectly with the N-terminus of BARD1 through the N-terminal interaction between BRCA1 and BARD1. The middle portion of BRCA1 binds directly to γ-tubulin, thereby mediating an indirect interaction between BRCA1 and OLA1. The N-terminus of BRCA1 interacted indirectly with γ-tubulin mediated by OLA1. The indirect C-terminal interaction between BRCA1 and OLA1 is most likely assisted by a still to be identified protein.