Selective Chemical Crosslinking Reveals a Cep57-Cep63-Cep152 Centrosomal Complex

Abstract

The centrosome functions as the main microtubule-organizing center of animal cells and is crucial for several fundamental cellular processes. Abnormalities in centrosome number and composition correlate with tumor progression and other diseases. Although proteomic studies have identified many centrosomal proteins, their interactions are incompletely characterized. The lack of information on the precise localization and interaction partners for many centrosomal proteins precludes comprehensive understanding of centrosome biology. Here, we utilize a combination of selective chemical crosslinking and superresolution microscopy to reveal novel functional interactions among a set of 31 centrosomal proteins. We reveal that Cep57, Cep63, and Cep152 are parts of a ring-like complex localizing around the proximal end of centrioles. Furthermore, we identify that STIL, together with HsSAS-6, resides at the proximal end of the procentriole, where the cartwheel is located. Our studies also reveal that the known interactors Cep152 and Plk4 reside in two separable structures, suggesting that the kinase Plk4 contacts its substrate Cep152 only transiently, at the centrosome or within the cytoplasm. Our findings provide novel insights into protein interactions critical for centrosome biology and establish a toolbox for future studies of centrosomal proteins.

Small organelle, big responsibility: the role of centrosomes in development and disease

“…R. Soc. B 369: 20130468 microcephaly and short stature [67,146]. Genome instability disorders such as Fanconi anaemia, Nijmegen breakage or Bloom syndromes also manifest with microcephaly and short stature, arguing for a vital role of genome integrity in neurogenesis and normal body size [147].…”

Cep57 Protein Is Required for Cytokinesis by Facilitating Central Spindle Microtubule Organization

“…Cep57 is a centrosome component recruited by NEDD1 (16) and forms a ring-like structure at the proximal end of the centriole, where it nucleates and stabilizes microtubules (27). During anaphase, the centrosome localization of Cep57 decreased.…”

New Trends in Near-Infrared Fluorophores for Bioimaging

“…107 Around 50 -60 nm bathochromic shifts were observed, 108 and due to the extreme photostability, some of those compounds are available for super-resolution microscopy, such as stimulated emission depletion (STED) imaging. 109,113,114 Si-pyronins (255) and Si-rhodamines (264, 294 -299), which were first reported by Xiao's group in 2008, 110 and further investigated by Nagano's group in 2011, 111 are among the most attractive fluorophores, because of their NIR absorption/emission spectra (over 650 nm) with high extinction coefficients (ca. 100000 M -1 cm -1 ) and quantum yields (0.3 -0.4 in aqueous buffer).…”