Cycads represent one of the most ancient lineages of living seed plants. Identifying genomic features uniquely shared by cycads and other extant seed plants, but not non-seed-producing plants, may shed light on the origin of key innovations, as well as the early diversification of seed plants. Here, we report the 10.5-Gb reference genome of Cycas panzhihuaensis, complemented by the transcriptomes of 339 cycad species. Nuclear and plastid phylogenomic analyses strongly suggest that cycads and Ginkgo form a clade sister to all other living gymnosperms, in contrast to mitochondrial data, which place cycads alone in this position. We found evidence for an ancient whole-genome duplication in the common ancestor of extant gymnosperms. The Cycas genome contains four homologues of the fitD gene family that were likely acquired via horizontal gene transfer from fungi, and these genes confer herbivore resistance in cycads. The male-specific region of the Y chromosome of C. panzhihuaensis contains a MADS-box transcription factor expressed exclusively in male cones that is similar to a system reported in Ginkgo, suggesting that a sex determination mechanism controlled by MADS-box genes may have originated in the common ancestor of cycads and Ginkgo. The C. panzhihuaensis genome provides an important new resource of broad utility for biologists.

Supramolecular chemistry has provided versatile and affordable solutions for the design of intelligent soft materials, but it cannot be applied in stiff materials. This paper describes a new concept for the design of high-performance supramolecular thermosets by using the noncovalent cation-π interaction as cross-linking. These supramolecular thermosets are a class of infusible and insoluble stiff polymers having excellent mechanical properties even at temperatures exceeding 300 °C. The cation-π interaction can be locally and reversibly installed and removed by aqueous treatments at high or low pH, respectively. Local manipulation of cross-linking confers these thermosets with multiple stimuli-responsive functions, such as recyclability, healability, adhesion, and nondestructive detection of cross-linking and mechanical properties.

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ORCID ID: 0000-0002-8009-4419 (X.H.).ABI5-BINDING PROTEIN2 (AFP2) negatively regulates the abscisic acid signal by accelerating ABI5 degradation during seed germination in Arabidopsis (Arabidopsis thaliana). The abscisic acid signal is reported to delay flowering by up-regulating Flowering Locus C expression, but the role of AFP2 in regulating flowering time is unknown. Here, we found that flowering time was markedly delayed and CONSTANS (CO) expression was reduced in a transgenic Arabidopsis line overexpressing AFP2 under LD conditions. Conversely, the loss-of-function afp2 mutant showed slightly earlier flowering, with higher CO expression. These data suggest that AFP2 negatively regulates photoperiod-dependent flowering time by modulating the CO signal. We then found that AFP2 exhibited circadian expression rhythms that peaked during the night. Furthermore, the C-terminus of AFP2 interacted with CO, while its N-terminal ethylene response factor-associated amphiphilic repression motif interacted with the transcriptional corepressor TOPLESS-related protein2 (TPR2). Thus, AFP2 bridges CO and TPR2 to form the CO-AFP2-TPR2 complex. Biochemical and genetic analyses showed that AFP2 mediated CO degradation during the night. AFP2 also recruited histone deacetylase activity at Flowering Locus T chromatin through its interaction with TPR2. Taken together, our results reveal an elaborate mechanism by which AFP2 modulates flowering time through coordinating the activity and stability of CO.

Hollow nickel silicate nanospheres (NiSiO3 NSs) with hierarchical shells were hydrothermally synthesized by using silica spheres as a template. The NiSiO3 NSs have an average diameter of 250 nm with a shell thickness of 50 nm, and the hierarchical shell consists of a large number of sheets. By taking advantage of the high affinity of Ni(2+) toward histidine-tagged (His-tagged) proteins, hollow NiSiO3 NSs can be used to enrich and separate His-tagged proteins directly from a mixture of lysed cells. Results indicated that the hollow NiSiO3 NSs presented negligible nonspecific protein adsorption and a high protein binding ability with a high binding capacity of 13.2 mmol g(-1). Their specificity and affinity toward His-tagged proteins remained after recycling 5 times. The hollow NiSiO3 NSs are especially suitable for rapid purification of His-tagged proteins.

An indole-based microporous organic polymer (PINK) is achieved and it exhibits good performance for carbon dioxide uptake via the local dipole–π interactions.

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