Uniform porous silicon hollow nano-spheres are prepared without any sacrificial templates through a magnesio-thermic reduction of mesoporous silica hollow nanospheres and surface modified by the following in situ chemical polymerization of polypyrrole. The porous hollow structure and polypyrrole coating contribute significantly to the excellent structure stability and high electrochemical performance of the nanocomposite.

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Tubulin is known to undergo unique post-translational modifications (PTMs), such as detyrosination and polyglutamylation, particularly in the unstructured carboxy-terminal tails (CTTs). However, more conventional PTMs of tubulin and their roles in the regulation of microtubule properties and functions remain poorly defined. Here, we report the comprehensive profiling of tubulin phosphorylation, acetylation, ubiquitylation, and O-GlcNAcylation in HeLa cells with a proteomic approach. Our tubulin-targeted analysis has identified 80 residues bearing single or multiple conventional PTMs including 24 novel PTM sites not covered in previous global proteomic surveys. By using a series of PTM-deficient or PTM-mimicking mutants, we further find that tubulin phosphorylation and acetylation play important roles in the control of microtubule assembly and stability. In addition, these tubulin PTMs have distinct effects on the retrograde transport of adenoviruses along microtubules. These findings thus enlarge the repertoire of tubulin PTMs and foster our understanding of their versatile roles in the regulation of microtubule dynamics and cellular functions.

Interstrand crosslinks (ICLs) are highly toxic DNA lesions that are repaired via a complex process requiring the coordination of several DNA repair pathways. Defects in ICL repair result in Fanconi anemia, which is characterized by bone marrow failure, developmental abnormalities, and a high incidence of malignancies. SLX4, also known as FANCP, acts as a scaffold protein and coordinates multiple endonucleases that unhook ICLs, resolve homologous recombination intermediates, and perhaps remove unhooked ICLs. In this study, we explored the role of SLX4IP, a constitutive factor in the SLX4 complex, in ICL repair. We found that SLX4IP is a novel regulatory factor; its depletion sensitized cells to treatment with ICL-inducing agents and led to accumulation of cells in the G2/M phase. We further discovered that SLX4IP binds to SLX4 and XPF–ERCC1 simultaneously and that disruption of one interaction also disrupts the other. The binding of SLX4IP to both SLX4 and XPF–ERCC1 not only is vital for maintaining the stability of SLX4IP protein, but also promotes the interaction between SLX4 and XPF–ERCC1, especially after DNA damage. Collectively, these results demonstrate a new regulatory role for SLX4IP in maintaining an efficient SLX4–XPF–ERCC1 complex in ICL repair.