Crystalline porous materials are currently a hot research topic in the field of proton-conducting materials. Crystalline porous materials include metal-organic frameworks (MOFs), coordination polymers (CPs), polyoxometalates (POMs) and covalent organic frameworks (COFs). The designable structures and high surface areas of these materials provide great opportunities to orderly accommodate proton carriers and to systemically modify the concentration and mobility of proton carriers in available spaces. Based on the understanding of the relationship between the structure and proton conductivity, controllable synthesis of porous materials with high proton conductivity will gradually be achieved. This review summarizes the emerging studies of these materials and their unique proton conductivities.

Summary The centrosome is the principal microtubule organizing center (MTOC) of animal cells [1]. Accurate centrosome duplication is fundamental for genome integrity and entails the formation of one procentriole next to each existing centriole, once per cell cycle. The procentriole then elongates to eventually reach the same size as that of the centriole. The mechanisms that govern elongation of the centriolar cylinder and their potential relevance for cell division are not known. Here, we show that the SAS-4-related protein CPAP [2] is required for centrosome duplication in cycling human cells. Furthermore, we demonstrate that CPAP overexpression results in the formation of abnormal long centrioles. This also promotes formation of more than one procentriole in the vicinity of such overly long centrioles, eventually resulting in the presence of supernumerary MTOCs. This in turn leads to multipolar spindle assembly and cytokinesis defects. Overall, our findings suggest that centriole length must be carefully regulated to restrict procentriole number and thus ensure accurate cell division.

G-protein-coupled receptors comprise the largest family of mammalian transmembrane receptors. They mediate numerous cellular pathways by coupling with downstream signalling transducers, including the hetrotrimeric G proteins G (stimulatory) and G (inhibitory) and several arrestin proteins. The structural mechanisms that define how G-protein-coupled receptors selectively couple to a specific type of G protein or arrestin remain unknown. Here, using cryo-electron microscopy, we show that the major interactions between activated rhodopsin and G are mediated by the C-terminal helix of the G α-subunit, which is wedged into the cytoplasmic cavity of the transmembrane helix bundle and directly contacts the amino terminus of helix 8 of rhodopsin. Structural comparisons of inactive, G-bound and arrestin-bound forms of rhodopsin with inactive and G-bound forms of the β-adrenergic receptor provide a foundation to understand the unique structural signatures that are associated with the recognition of G, G and arrestin by activated G-protein-coupled receptors.

A sensor with a red‐emission signal is successfully obtained by the solvothermal reaction of Eu3+ and heterofunctional ligand bpydbH2 (4,4′‐(4,4′‐bipyridine‐2,6‐diyl) dibenzoic acid), followed by terminal‐ligand exchange in a single‐crystal‐to‐single‐crystal transformation. As a result of treatments both before and after the metal–organic framework formation, accessible Lewis‐base sites and coordinated water molecules are successfully anchored onto the host material, and they act as signal transmission media for the recognition of analytes at the molecular level. This is the first reported sensor based on a metal–organic framework (MOF) with multi‐responsive optical sensing properties. It is capable of sensing small organic molecules and inorganic ions, and unprecedentedly it can discriminate among the homologues and isomers of aliphatic alcohols as well as detect highly explosive 2,4,6‐trinitrophenol (TNP) in water or in the vapor phase. This work highlights the practical application of luminescent MOFs as sensors, and it paves the way toward other multi‐responsive sensors by demonstrating the incorporation of various functional groups into a single framework.

Highlights d 3.2-Å cryo-EM structure of the CB2-G i complex bound to potent agonist WIN 55,212-2 d Algorithm developed for quantitative characterization of binding residues d Structural determinants for distinguishing CB2 agonists from antagonists d CB2-Gi binding features and different activation mechanisms of CB2 and CB1

A series of lanthanide metal‐organic frameworks (Ln‐MOFs) are synthesized through solvothermal conditions with 1,3‐bis(4‐carboxyphenyl)imidazolium (H2L). Owing to the lanthanide contraction effect, two different types of Ln‐MOFs, namely, {[Ln(L)2(OH)]·3H2O}n (Ln:Pr, Nd, Sm) and {[Ln(L)2(COO)(H2O)2]·H2O}n (Ln: Eu, Gd, Tb, Dy, Tm, Yb, Y), and their corresponding codoped Ln‐MOFs EuxTb1‐xL are obtained. With careful adjustment of the relative concentration of the lanthanide ions and the excitation wavelength, the color of the luminescence can be systematically modulated and white light emission can be further successfully achieved. Furthermore, by virtue of the temperature‐dependent luminescent behavior, Eu0.2Tb0.8L allows for the design of a thermometer with an excellent linear response to temperature over a wide range, from 40 to 300 K. This work highlights the practical applications of Ln‐MOFs for tailoring fluorescent color and even obtaining practical white light emission, and especially for sensing temperature as luminescent thermometers in a single framework by controlling in different ways.

Intricate interactions between kinetochores and microtubules are essential for the proper distribution of chromosomes during mitosis. A crucial long-standing question is how vertebrate kinetochores generate chromosome motion while maintaining attachments to the dynamic plus ends of the multiple kinetochore MTs (kMTs) in a kinetochore fibre. Here, we demonstrate that individual kMTs in PtK(1) cells are attached to the kinetochore outer plate by several fibres that either embed the microtubule plus-end tips in a radial mesh, or extend out from the outer plate to bind microtubule walls. The extended fibres also interact with the walls of nearby microtubules that are not part of the kinetochore fibre. These structural data, in combination with other recent reports, support a network model of kMT attachment wherein the fibrous network in the unbound outer plate, including the Hec1-Ndc80 complex, dissociates and rearranges to form kMT attachments.

SignificanceThe Mycobacterium tuberculosis (Mtb) ClpB is a ring-shaped, ATP-driven disaggregase. The ability to rescue aggregated proteins is crucial for Mtb to grow and persist in the host. Despite extensive studies in the past two decades, it is still not well understood how a bacterial disaggregase couples ATP binding and hydrolysis to peptide translocation. Our cryo-EM study of the Mtb ClpB in the presence of a peptide substrate and the slowly hydrolysable adenosine 5′-[γ-thio]triphosphate revealed two active conformations in the midst of the substrate-threading process. This, together with the resolved nucleotide state in each of the 12 nucleotide-binding domains of the ClpB hexamer, helps define a detailed atomic trajectory that couples ATP binding and hydrolysis to mechanical protein translocation.