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The hypothalamus plays a vital role in coordinating essential neuroendocrine, autonomic, and somatomotor responses for survival and reproduction. While previous studies have explored population-level projections of hypothalamic neurons, the specific innervation patterns of individual hypothalamic axons remain unclear. To understand the organization of hypothalamic axon projections, we conducted a comprehensive reconstruction of single-cell projectomes from 7,180 mouse hypothalamic neurons expressing specific neuropeptides. Our analysis identified 31 distinct subtypes based on projectome-defined characteristics, with many exhibiting long-range axon collateral projections to multiple brain regions. Notably, these subtypes selectively targeted specific subdomains within downstream areas, either unilaterally or bilaterally. Furthermore, we observed that individual peptidergic neuronal types encompassed multiple projectome-defined subtypes, explaining their diverse functional roles. Additionally, by examining intra-hypothalamic axon projections, we uncovered six modular subnetworks characterized by enriched intramodular connections and distinct preferences for downstream targets. This modular organization of the intra-hypothalamic network likely contributes to the coordinated organization of hypothalamic outputs. In summary, our comprehensive projectome analysis reveals the organizational principles governing hypothalamic axon projections, providing a framework for understanding the neural circuit mechanisms underlying the diverse and coordinated functions of the hypothalamus.

Presynaptic syntaxin binding protein 1 (STXBP1) is essential for neurotransmitter release. Heterozygous mutations in this protein cause STXBP1 encephalopathy (STXBP1-E), which is characterized by intellectual disabilities and epilepsies. Since nonhuman primates closely resemble humans, monkey models may advance studies on the pathogenesis and therapeutic treatments of STXBP1-E. We generated cynomolgus monkeys carrying STXBP1 (R292H) mutation through base editing of in vitro fertilized embryos to mimic a clinical condition. The newborn STXBP1-edited monkeys exhibited focal epilepsy, and the animal that survived beyond the first week postpartum presented typical EEG phenotypes. Biochemical analysis of brain biopsy samples showed reduced levels of STXBP1 (MUNC18-1) and SNARE complex proteins. Single-cell sequencing identified one specific cell cluster that may contribute to encephalopathy. Thus, our case report shows that base-edited STXBP1 mutant monkeys are a good animal model for STXBP1-E, and that a base-editing approach is useful for generating primate models of human genetic disorders.

Background Influenza A virus (IAV) evolves strategies to counteract the host antiviral defense for establishing infection. The influenza A virus (IAV) non-structural protein 1 (NS1) is a key viral factor shown to counteract type I IFN antiviral response mainly through targeting RIG-I signaling. Growing evidence suggests that viral RNA sensors RIG-I, TLR3, and TLR7 function to detect IAV RNA in different cell types to induce type I IFN antiviral response to IAV infection. Yet, it remains unclear if IAV NS1 can exploit a common mechanism to counteract these RNA sensing pathways to type I IFN production at once, then promoting viral propagation in the host. Methods Luciferase reporter assays were conducted to determine the effect of NS1 and its mutants on the RIG-I and TLR3 pathways to the activation of the IFN-β and NF-κB promoters. Coimmunoprecipitation and confocal microscopic analyses were used to the interaction and colocalization between NS1 and TRAF3. Ubiquitination assays were performed to study the effect of NS1 and its mutants on TRAF3 ubiquitination. A recombinant mutant virus carrying NS1 E152A/E153A mutations was generated by reverse genetics for biochemical, ex vivo, and in vivo analyses to explore the importance of NS1 E152/E153 residues in targeting the RNA sensing-TRAF3-type I IFN axis and IAV pathogenicity. Results Here we report that NS1 subverts the RIG-I, TLR3, and TLR7 pathways to type I IFN production through targeting TRAF3 E3 ubiquitin ligase. NS1 harbors a conserved FTEE motif (a.a. 150-153), in which the E152/E153 residues are critical for binding TRAF3 to block TRAF3 ubiquitination and type I IFN production by these RNA sensing pathways. A recombinant mutant virus carrying NS1 E152A/E153A mutations induces higher type I IFN production ex vivo and in vivo, and exhibits the attenuated phenotype in infected mice, indicating the importance of E152/E153 residues in IAV pathogenicity. Conclusions Together our work uncovers a novel mechanism of IAV NS1-mediated immune evasion to promote viral infection through targeting the RNA sensing-TRAF3-type I IFN axis.

Circadian disruption is a risk factor for metabolic, psychiatric and age-related disorders, and non-human primate models could help to develop therapeutic treatments. Here, we report the generation of BMAL1 knockout cynomolgus monkeys for circadian-related disorders by CRISPR/Cas9 editing of monkey embryos. These monkeys showed higher nocturnal locomotion and reduced sleep, which was further exacerbated by a constant light regimen. Physiological circadian disruption was reflected by the markedly dampened and arrhythmic blood hormonal levels. Furthermore, BMAL1-deficient monkeys exhibited anxiety and depression, consistent with their stably elevated blood cortisol, and defective sensory processing in auditory oddball tests found in schizophrenia patients. Ablation of BMAL1 up-regulated transcriptional programs toward inflammatory and stress responses, with transcription networks associated with human sleep deprivation, major depressive disorders, and aging. Thus, BMAL1 knockout monkeys are potentially useful for studying the physiological consequences of circadian disturbance, and for developing therapies for circadian and psychiatric disorders.

Cloning of macaque monkeys by somatic cell nucleus transfer (SCNT) allows the generation of monkeys with uniform genetic backgrounds that are useful for the development of non-human primate models of human diseases. Here, we report the feasibility of this approach by SCNT of fibroblasts from a macaque monkey (Macaca fascicularis), in which a core circadian transcription factor BMAL1 was knocked out by clustered regularly interspaced short palindromic repeat/Cas9 gene editing (see accompanying paper). Out of 325 SCNT embryos transferred into 65 surrogate monkeys, we cloned five macaque monkeys with BMAL1 mutations in both alleles without mosaicism, with nuclear genes identical to that of the fibroblast donor monkey. Further peripheral blood mRNA analysis confirmed the complete absence of the wild-type BMAL1 transcript. This study demonstrates that the SCNT approach could be used to generate cloned monkeys from fibroblasts of a young adult monkeys and paves the way for the development of macaque monkey disease models with uniform genetic backgrounds.

Summary SIRT7 is a member of the mammalian sirtuins and functions as an NAD+-dependent deacylase. Here we show that SIRT7 deficiency leads to a lowered histone acetyltransferase 1 (HAT1) activity and therefore decreased histone H4K5 and H4K12 acetylation. This in turn causes CENP-A dislocation at the centromere, which further affects chromatin assembly. SIRT7 ablation results in aneuploidy and aging phenotypes, including senescence and nucleolar expansion. Moreover, SIRT7 knockout mice are susceptible to DSS-induced colitis and alcohol-derived epithelial disturbance, revealing a disrupted intestinal epithelial homeostasis. Notably, absence of SIRT7 aggravates the susceptibility of colorectal cancer incidence in APCMin/+ mouse model and elicits further the Wnt signaling. Our findings indicate a tumor suppressive role of SIRT7 in the case of colorectal cancer. Together with the activities in maintaining genome integrity and intestinal homeostasis, activating SIRT7 may serve as a strategy to treat bowel diseases and colorectal cancer., Graphical Abstract, Highlights • SIRT7 deacetylates HAT1 further regulates CENP-A nucleosome assembly • SIRT7 preserves genome integrity and intestinal homeostasis • SIRT7-ablation leads to intestinal tumorigenesis, Molecular Biology; Molecular Genetics; Cancer

Circadian clock and cell cycle are vital cellular programs acting in a timely-regulated, cyclic manner. The two cellular oscillators are coupled in various ways to facilitate biological processes. Here we report CDK9, a kinase belongs to the CDK family in regulating cell cycle and RNA Pol II activity, can serve as a modulator for circadian clock. We identified CDK inhibitor LY2857785 potently blocked PER2:LUC expression in MEFs from a screen of 17 commonly-used CDK inhibitors. We further analyzed the possible targets of LY2857785 by siRNA approach, and confirmed CDK9 as the main effector. LY2857785 treatment, as well as Cdk9 knock-down, led to lowered expression of Bmal1 in accordance with elevated expression of Rev-Erbα. CDK9 associated with REV-ERBα thus attenuated REV-ERBα binding to the RORE for Bmal1 suppression. To conform the circadian-modulating activity of CDK9 in vivo, we knocked down CDK9 in mice at the anterior hypothalamus covering the central oscillator SCN, and found the respiratory exchange ratio, daily activity and circadian period were altered in the Cdk9-knockdown mice. Together, our finding designated CDK9 as a novel modulator in circadian clock. CDK9 may serve as a vital basis to understand circadian- and cell cycle-misregulated ailments such as cancer.

We suggest that super diffraction of light can be realized with a planar plasmonic metasurface, i.e., a single-layer metal surface with super-wavelength asymmetric grooves. The structure of the system is simple and easy to be fabricated in experiments. The efficiency of +1st-order diffraction of the carefully designed metasurface is higher than 50% over a broadband width of over 1350 nm in the near infrared regime while –1st-order diffraction and the 0th-order reflection are suppressed. The physical mechanism of the anomalous diffractions can be attributed to the collective effect of single grooves in the metasurface. The design may have important applications in the beam splitters, spectroscopy studies, and thin-film solar cells.

An in-house developed full-vector finite-element imaginary-distance beam propagation method (FV-FE-ID-BPM) is employed to calculate the modes of a surface plasmon metal-stripe waveguide. Leaky modes, which possess less propagation losses compared with corresponding bound modes, are particularly studied. The calculated real and imaginary parts of the modal effective indices are shown to be with local-overshoot characteristics versus the stripe width when fine width steps are used. Using fine enough spatial mesh resolution, the field profile within the metal-stripe region is revealed and examined, and the local-overshoot characteristics could be correlated with the integer number of quasi-periods associated with the field variation along the interface between the metal stripe and the substrate.

Background Circadian rhythms are oscillating physiological and behavioral changes governed by an internal molecular clock, and dysfunctions in circadian rhythms have been associated with ageing and various neurodegenerative diseases. However, the evidence directly connecting the neurodegeneration-associated proteins to circadian control at the molecular level remains sparse. Methods Using meta-analysis, synchronized animals and cell lines, cells and tissues from FUS R521C knock-in rats, we examined the role of FUS in circadian gene expression regulation. Results We found that FUS, an oscillating expressed nuclear protein implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), exerted a novel feedback route to regulate circadian gene expression. Nr1d1-encoded core circadian protein REV-ERBα bound the Fus promoter and regulated the expression of Fus. Meanwhile, FUS was in the same complex as PER/CRY, and repressed the expression of E box-containing core circadian genes, such as Per2, by mediating the promoter occupancy of PSF-HDAC1. Remarkably, a common pathogenic mutant FUS (R521C) showed increased binding to PSF, and caused decreased expression of Per2. Conclusions Therefore, we have demonstrated FUS as a modulator of circadian gene expression, and provided novel mechanistic insights into the mutual influence between circadian control and neurodegeneration-associated proteins. Electronic supplementary material The online version of this article (10.1186/s40035-018-0131-y) contains supplementary material, which is available to authorized users.

Mutations in fused in sarcoma (Fus) cause familial amyotrophic lateral sclerosis (ALS) and occasionally frontotemporal dementia. Here we report the establishment and characterization of a novel knockin (KI) rat model expressing a Fus point mutation (R521C) via CRISPR/Cas9. The mutant animals developed adult-onset learning and memory behavioral deficits, with reduced spine density in hippocampal neurons. Remarkably, sleep-wake cycle and circadian abnormalities preceded the onset of cognitive deficit. RNA-seq study further demonstrated altered expression of some key sleep and circadian regulators, such as orexin/hypocretin receptor type 2 and casein kinase 1 epsilon, in the mutant rats. Therefore, we have established a rodent model expressing physiological level of a pathogenic mutant FUS, and we found cognitive impairment as a main behavioral deficit at mid age. Furthermore, we have revealed a new role of FUS in sleep and circadian regulation and demonstrated that functional change in FUS could cause sleep-wake and circadian disturbance as early symptoms.

Table S2. Predicted REV-ERBÎą-binding site on FUS promoter. (DOCX 14 kb)

Figure S1. The establishment of R521C FUS knock-in (KI) rats. (DOCX 92 kb)

Table S1. Primer sequences. (DOCX 17 kb)

We design a series of plasmonic bowtie antennas with broadly varying resonant wavelengths from 1.34 to 3.36 $\mu\hbox{m}$ under the same antenna footprint size. Based on the prototype of contour bowtie antennas (CBAs), we modify the geometry of CBAs with extensive resonant paths and, therefore, redshift resonances and maintain the gap enhancement factors, at least at the same level with that of the solid bowtie antenna.

Dysregulation of ribosome biogenesis causes human diseases, such as Diamond-Blackfan anemia, del (5q-) syndrome and bone marrow failure. However, the mechanisms of blood disorders in these diseases remain elusive. Through genetic mapping, molecular cloning and mechanism characterization of the zebrafish mutant cas002, we reveal a novel connection between ribosomal dysfunction and excessive autophagy in the regulation of hematopoietic stem/progenitor cells (HSPCs). cas002 carries a recessive lethal mutation in kri1l gene that encodes an essential component of rRNA small subunit processome. We show that Kri1l is required for normal ribosome biogenesis, expansion of definitive HSPCs and subsequent lineage differentiation. Through live imaging and biochemical studies, we find that loss of Kri1l causes the accumulation of misfolded proteins and excessive PERK activation-dependent autophagy in HSPCs. Blocking autophagy but not inhibiting apoptosis by Bcl2 overexpression can fully rescue hematopoietic defects, but not the lethality of kri1l(cas002) embryos. Treatment with autophagy inhibitors (3-MA and Baf A1) or PERK inhibitor (GSK2656157), or knockdown of beclin1 or perk can markedly restore HSPC proliferation and definitive hematopoietic cell differentiation. These results may provide leads for effective therapeutics that benefit patients with anemia or bone marrow failure caused by ribosome disorders.

A single silver nanowire with a silica substrate possesses a silver/substrate guided mode and an air/silver leaky mode, the latter being found recently by this group. In this work, further study is conducted by considering coupling between such two nanowires and the corresponding surface plasmon guided and leaky modes are numerically calculated for 500- to 2000-nm wavelength range. The waveguide mode solutions are based on an in-house developed full-vector finite-element imaginary-distance beam propagation method.

The light-transmission resonant behavior of complex-shaped patterns can be difficult to estimate intuitively due to many possible resonant contours. In this paper, we propose a simple method to predict the effective resonant paths of onefold or twofold mirror-symmetry patterns, which exploits the antiphase property of certain field component along the resonant path and the symmetry requirement associated with the incident-wave polarization state. In addition, the resonant wavelengths for aperture-type patterns can further be estimated by a simple modified cutoff wavelength equation for a rectangular waveguide. Such prediction is validated by the simulated results of the finite-difference time domain method. In addition, we discuss how the separation distance between slit elements in the aperture affects the resonant wavelength, showing how the coupling between adjacent slits would play a role in the variation of the spectra. By studying the properties of such factors and how they interact in detail, we could manipulate the spectra with an additional degree of freedom, which could be important to structures with multielements in one unit cell.

SummarySIRT1 is a NAD+-dependent protein deacetylase that governs many physiological pathways, including circadian rhythm in peripheral tissues. Here, we show that SIRT1 in the brain governs central circadian control by activating the transcription of the two major circadian regulators, BMAL1 and CLOCK. This activation comprises an amplifying circadian loop involving SIRT1, PGC-1α, and Nampt. In aged wild-type mice, SIRT1 levels in the suprachiasmatic nucleus are decreased, as are those of BMAL1 and PER2, giving rise to a longer intrinsic period, a more disrupted activity pattern, and an inability to adapt to changes in the light entrainment schedule. Young mice lacking brain SIRT1 phenocopy these aging-dependent circadian changes, whereas mice that overexpress SIRT1 in the brain are protected from the effects of aging. Our findings indicate that SIRT1 activates the central pacemaker to maintain robust circadian control in young animals, and a decay in this activity may play an important role in aging.

A new multidomain pseudospectral frequency-domain (PSFD) method based on the Legendre polynomials with penalty scheme is developed for numerically modeling electromagnetic wave scattering problems. The primary aim of the proposed method is to more accurately analyzing scattering and coupling problems in plasmonics, in which optical waves interact with nanometer-sized metallic structures. Using light scattering by a silver circular cylinder as a first example, the formulated method is demonstrated to achieve numerical accuracy in near-field calculations on the order of 10-9 with respect to a unity field strength of the incident wave with excellent exponentially convergent behavior in numerical accuracy. Then, scattering by a dielectric square cylinder and that by several coupled metallic structures involving circular cylinders, square cylinders, or dielectric coated cylinders are examined to provide high-accuracy coupled near-field results.

The second-order conditions of the Yee-grid based FDTD method at sloped planar dielectric interfaces are studied. The theoretical analysis is performed for TE waves. It is found that second-order accuracy can be achieved if the averaging process for the effective permittivities is taken along the normal direction to the dielectric interface. The length of average depends on the relative orientation of the interface in the FDTD mesh. The proposed line average scheme is more accurate than the traditional cell average scheme, and is validated for the scattering by a dielectric cylinder. Due to its simplicity, the proposed line average scheme needs much less time in the preprocessing stage of the FDTD calculation to get the proper values of effective permittivities, as compared with the traditional cell average scheme. The proposed line average scheme is also applied to TM waves, and gives at least 3.3 dB better results than other methods.

Waveguide modes propagating along the circular-cylinder silver nanowire on a silica substrate are calculated and studied using an in-house developed full-vector finite-element imaginary-distance beam propagation method (FV-FE-IDBPM). In particular, leaky-mode characteristics for the mode with field guided mainly at the top air-silver interface and that with field distributed mainly near the silver-substrate interface are presented and discussed based on high-resolution numerical analysis. Complex effective indices are accurately solved from which the modal propagation lengths are determined.

We propose a pseudospectral mode solver for optical waveguide mode analysis formulated by the frequency-domain Maxwell equations. Special attention is paid upon identifying the required boundary operator for the formulation and the relationships between the derived operator and the physical boundary conditions. These theoretical results are adopted into a Legendre pseudospectral multidomain computational framework to compute the propagation characteristics of optical waveguides. Numerical experiments are conducted, and the expected spectral convergence of the scheme is observed for smooth problems and for problems having field jumps at material interfaces. For dielectric waveguides with sharp corners, the spectral convergence is lost due to the singular nature of fields at the corner. Nevertheless, compared with other methods, the present formulation remains as an efficient approach to obtain waveguide modes.