中央研究院 原子與分子科學研究所

Subdistal appendages (sDAPs) are centriolar elements observed proximal to the distal appendages (DAPs) in vertebrates. Despite their obvious presence, structural and functional understanding of sDAPs remains elusive. Here, by combining super-resolved localization analysis and CRISPR-Cas9 genetic perturbation, we find that, although DAPs and sDAPs are primarily responsible for distinct functions in ciliogenesis and microtubule anchoring respectively, the presence of one element actually affects the positioning of the other. Specifically, we find dual layers of both ODF2 and CEP89, where their localizations are differentially regulated by DAP and sDAP integrity. DAP depletion relaxes longitudinal occupancy of sDAP protein ninein to cover the DAP region, implying a role of DAPs in sDAP positioning. Removing sDAPs alter the distal border of centrosomal γ-tubulins, illustrating a new role of sDAPs. Together, our results provide an architectural framework of sDAPs to shed light on functional understanding, surprisingly revealing the coupling between DAPs and sDAPs.

Fluorescent nanodiamond (FND) containing nitrogen-vacancy (NV) centers as built-in fluorophores exhibits a nearly constant emission profile over 550 – 750 nm upon excitation by vacuum-ultraviolet (VUV), extreme ultraviolet (EUV), and X- radiations from a synchrotron source over the energy (wavelength) range of 6.2 – 1450 eV (0.86 – 200 nm).  The photoluminescence (PL) quantum yield of FND increases steadily with the increasing excitation energy, attaining a value as great as 1700% at 700 eV (1.77 nm).  Notably, the yield curve is continuous, having no gap in the VUV to X-ray region.  In addition, no significant PL intensity decreases were observed for hours.  Applying the FND sensor to measure the absorption cross sections of gaseous O₂ over 110 – 200 nm and comparing the measurements with the sodium-salicylate scintillator, we obtained results in agreement with each other within 5%.  The superb photostability and broad applicability of FND offer a promising solution for the long-standing problem of lacking a robust and reliable detector for VUV, EUV, and X- radiations.