The tetratricopeptide repeat protein OsTPR075 promotes heading by regulating florigen transport in rice.

Rice (Oryza sativa) is one of the most important crops worldwide. Heading date is a vital agronomic trait that influences rice yield and adaption to local conditions. Hd3a, a proposed florigen that primarily functions under short-day (SD) conditions, is a mobile flowering signal that promotes the floral transition in rice. Nonetheless, how Hd3a is transported from leaves to the shoot apical meristem (SAM) under SDs remains elusive. Here, we report that FT-INTERACTING PROTEIN9 (OsFTIP9) specifically regulates rice flowering time under SDs by facilitating Hd3a transport from companion cells (CCs) to sieve elements (SEs). Furthermore, we show that the tetratricopeptide repeat (TPR) protein OsTPR075 interacts with both OsFTIP9 and OsFTIP1 and strengthens their respective interactions with Hd3a and the florigen RICE FLOWERING LOCUS T1 (RFT1). This in turn affects the trafficking of Hd3a and RFT1 to the SAM, thus regulating flowering time under SDs and long-day conditions, respectively. Our findings suggest that florigen transport in rice is mediated by different OsFTIPs under different photoperiods and those interactions between OsTPR075 and OsFTIPs are essential for mediating florigen movement from leaves to the SAM.

SNAC1-OsERF103-OsSDG705 module mediates drought response in rice.

Drought stress profoundly hampers both plant growth and crop yield. To combat this, plants have evolved intricate transcriptional regulation mechanisms as a pivotal strategy. Through a genetic screening with rice genome-scale mutagenesis pool under drought stress, we identified an APETALA2/Ethylene Responsive Factor, namely OsERF103, positively responds to drought tolerance in rice. Combining chromatin immunoprecipitation sequencing and RNA sequencing analyses, we pinpointed c. 1000 genes directly influenced by OsERF103. Further results revealed that OsERF103 interacts with Stress-responsive NAC1 (SNAC1), a positive regulator of drought tolerance in rice, to synergistically regulate the expression of key drought-related genes, such as OsbZIP23. Moreover, we found that OsERF103 recruits a Su(var)3-9,enhancer of zeste and trithorax-domain group protein 705, which encodes a histone 3 lysine 4 (H3K4)-specific methyltransferase to specifically affect the deposition of H3K4me3 at loci like OsbZIP23 and other genes linked to dehydration responses. Additionally, the natural alleles of OsERF103 are selected during the domestication of both indica and japonica rice varieties and exhibit significant geographic distribution. Collectively, our findings have unfurled a comprehensive mechanistic framework underlying the OsERF103-mediated cascade regulation of drought response. This discovery not only enhances our understanding of drought signaling but also presents a promising avenue for the genetic improvement of drought-tolerant rice cultivars.

A Machine Learning Model Based on GRU and LSTM to Predict the Environmental Parameters in a Layer House, Taking CO2 Concentration as an Example.

In a layer house, the CO2 (carbon dioxide) concentration above the upper limit can cause the oxygen concentration to be below the lower limit suitable for poultry. This leads to chronic CO2 poisoning in layers, which manifests as listlessness, reduced appetite, weak constitution, decreased production performance, and weakened resistance to disease. Regulating ventilation may ensure a suitable CO2 concentration in layer houses. Predicting the changes in CO2 concentration and regulating the CO2 concentration in advance are key to ensuring healthy large-scale breeding of layers. In recent years, machine learning and deep learning methods have been increasingly applied to this field. A CO2 prediction model for layer house is proposed based on a GRU (gated recurrent unit) and LSTM (long short-term memory). The temperature, humidity, and CO2 were determined as inputs to the model by the correlation coefficient. The datasets of the experimental layer house were continuously measured during June-July 2023, using a self-developed environmental monitor, and the monitored data were used as samples for model inputs. There were 22,000 time series data in the datasets. In this study, multivariate time series data were standardized via data pre-processing to improve model training. GRU and LSTM models were constructed. The models were trained using a training set. Then, these trained models were used to provide predictions on a test set. The prediction errors were calculated using the true values of the test set and the predicted values provided by the models. To test the performance of the model and accuracy of the predictions, predictions were made for different numbers of datasets. The results demonstrated that the combined prediction model had good generalization, stability, and convergence with high prediction accuracy. Due to the structure of the model, the stability of the LSTM model was higher than that of the GRU model, and its prediction accuracy and speed were lower than those of the GRU model. When the datasets of the GRU model were 15,000 to 17,000, The MAE of the GRU was 70.8077 to 126.7029 ppm, and the prediction time of the GRU is 16 to 24 ms. When the LSTM model's datasets were 15,000-20,000, the MAE of LSTM was 78.8596 to 136.0896 ppm, and the prediction time of the GRU was 17 to 26 ms.

Effect of different implant angulations on the biomechanical performance of prosthetic screws in two implant-supported, screw-retained prostheses: A numerical and experimental study.

STATEMENT OF PROBLEM: A mesiodistal angle frequently forms between 2 splinted implant-supported, screw-retained fixed dental prostheses (TIS-FDPs). Mechanical complications commonly occur in prosthetic screws. Studies regarding the effect of the degree of implant angulation on the biomechanical performance of prosthetic screws in TIS-FDPs are sparse. PURPOSE: The purpose of this numerical and experimental study was to investigate the effects of different implant angulations on the biomechanical performance, including stress distribution, stability of the screw joint, and surface morphology change of the prosthetic screws in TIS-FDPs. MATERIAL AND METHODS: TIS-FDPs were classified into 4 groups: 0, 10, 20, and 30 degrees based on the degree of mesiodistal angle between the long axes of the 2 implants. In the finite element analysis (FEA), 4 series of 3D models were constructed and loaded with simulated occlusal forces. The von Mises stresses and rotational angles of the prosthetic screws were then calculated. In the mechanical test, each group of 5 TIS-FDPs with 10 prosthetic screws was tested under 1 million loading cycles by using a universal testing machine. The removal torque values (RTVs) and the surface roughness of the prosthetic screws were measured after cyclic loading. The normality of the outcome variables was assessed by the Shapiro-Wilk test. Analysis of variance and the Kruskal-Wallis test were used for further analysis (α=.05). RESULTS: The FEA results showed that the von Mises stresses of the prosthetic screws were concentrated in the first screw thread crest engaged with the abutment, and the maximum values of the threads and the rotation angles of the prosthetic screws increased in the 2-implant mesiodistal angulation from 0 to 30 degrees. The mechanical tests showed that the RTVs of the prosthetic screws in each group were not significantly different after 1 million loading cycles (P=.107). The surface roughness of the crest of the first 2 threads of the prosthetic screws in the 30-degree group changed significantly compared with those in the other groups. CONCLUSIONS: When TIS-FDPs were delivered, larger angulations of the 2 splinted implants seemed to increase the stress concentrated on the crest of the first engaged thread and the rotation angles of the prosthetic screws. After 1 million loading cycles, significant surface adhesive wear was identified on the crest of the first 2 threads of the prosthetic screws in the 30-degree group compared with groups with a smaller angulation.

MicroRNA-31 mediated by interferon regulatory factor 7 signaling facilitates control of Mycobacterium tuberculosis infection.

Tuberculosis (TB) induced by Mycobacterium tuberculosis (M. tuberculosis) infection remains a global most deadly infectious disease. While development of more effective TB vaccines and therapeutics relies on identifications of true biomarkers designating an immune protection against M. tuberculosis infection, exact protective immune components against M. tuberculosis infection remain largely unidentified. We previously found that severe TB induced remarkable up-regulation of interferon regulatory factor 7 (IRF7) and IRF7-related gene signatures, implicating that some unknown downstream molecules in IRF7 signaling cascades may determine the M. tuberculosis infection outcomes and serve as a protective immune component against M. tuberculosis infection. Indeed, here, we observe that genetic ablation of IRF7 leads to more severe lung pathology, increased M. tuberculosis burdens, impaired differentiation of effector/memory T subsets, and extensively elevated expression of pro-inflammatory cytokines in lungs. Importantly, IRF7 is vital for sustaining expression of PD-1/PD-L1 and PD-1/PD-L1-modulated miRNA-31. Moreover, interventions of miRNA-31 expressions via administration of miRNA-31 agomir reduces lung pathology and bacilli burdens via inducing up-regulation of gene sets involved in biological processes of defense response or cellular and chemical homeostasis in lungs. Thus, this study uncovers previously unrecognized importance and mechanisms of IRF7-mediated miRNA-31 as a protective immune component against M. tuberculosis infection.

General Approach to N6,C5'-Difunctionalization of Adenosine.

Among the C6-halo purine ribonucleosides, the readily accessible 6-chloro derivative has been known to undergo slow SNAr reactions with amines, particularly aryl amines. In this work, we show that in 0.1 M AcOH in EtOH, aryl amines react quite efficiently at the C6-position of 2',3',5'-tri-O-(t-BuMe2Si)-protected 6-chloropurine riboside (6-ClP-riboside), with concomitant cleavage of the 5'-silyl group. These two-step processes proceeded in generally good yields, and notably, reactions in the absence of AcOH were much slower and/or lower yielding. Corresponding reactions of 2',3',5'-tri-O-(t-BuMe2Si)-protected 6-ClP-riboside with alkyl amines proceeded well but without desilylation at the primary hydroxyl terminus. These differences are likely due to the acidities of the ammonium chlorides formed in these reactions, and the role of AcOH was not desilylation but possibly only purine activation. With 50% aqueous TFA in THF at 0 °C, cleavage of the 5'-silyl group from 2',3',5'-tri-O-(t-BuMe2Si)-protected N6-alkyl adenosine derivatives and from 6-ClP-riboside was readily achieved. Reactions of the 5'-deprotected 6-ClP-riboside with alkyl amines proceeded in high yields and under mild conditions. Because these complementary methodologies yielded N6-aryl and -alkyl adenosine derivatives containing a free 5'-hydroxyl group, a variety of product functionalizations were undertaken to yield N6,C5'-doubly modified nucleoside analogues.

Efficacy and safety of omalizumab in Chinese patients with anti-histamine refractory chronic spontaneous urticaria.

Chronic spontaneous urticaria (CSU) is characterized by the spontaneous development of wheals, itching, and/or angioedema, for ≥6 weeks. In China, non-sedating H1-antihistamines (H1AH) are the recommended first-line treatment, with escalation up to 4× the standard dose in symptomatic patients to achieve control. Treatment options for Chinese patients who remain symptomatic on H1AH treatment are limited. This 20-week randomized, double blind, placebo-controlled, parallel-group study investigated the efficacy and safety of omalizumab as an add-on therapy for the treatment of patients with CSU who remained symptomatic despite H1AH treatment in China. Adult patients (N = 418) diagnosed with refractory CSU for ≥6 months were randomized (2:2:1) to receive omalizumab 300 mg (OMA300), omalizumab 150 mg (OMA150) or placebo, subcutaneously, every 4 weeks. Primary outcome was change from baseline to week 12 in weekly itch severity score (ISS7). Safety was assessed by rates of adverse events (AEs). Demographic and disease characteristics at baseline were comparable across treatment groups. At week 12, statistically significant greater decreases from baseline were observed in ISS7 with OMA300 (least square mean difference [LSM]: -4.23; 95% confidence interval [CI]: -5.70, -2.77; p < 0.001) and OMA150 (LSM: -3.79; 95% CI: -5.24, -2.33; p < 0.001) versus placebo. Incidence of treatment-emergent AEs over 20 weeks was slightly higher with OMA300 (71.3%) compared to OMA150 and placebo groups (64.7% and 63.9%, respectively). The incidences of serious AEs were balanced between groups. This study demonstrated the efficacy and safety of omalizumab in Chinese adult patients with CSU who remained symptomatic despite H1AH therapy.

Fast modal analysis for Hermite-Gaussian beams via deep learning.

The eigenmodes of Hermite-Gaussian (HG) beams emitting from solid-state lasers make up a complete and orthonormal basis, and they have gained increasing interest in recent years. Here, we demonstrate a deep learning-based mode decomposition (MD) scheme of HG beams for the first time, to the best of our knowledge. We utilize large amounts of simulated samples to train a convolutional neural network (CNN) and then use this trained CNN to perform MD. The results of simulated testing samples have shown that our scheme can achieve an averaged prediction error of 0.013 when six eigenmodes are involved. The scheme takes only about 23 ms to perform MD for one beam pattern, indicating promising real-time MD ability. When larger numbers of eigenmodes are involved, the method can also succeed with slightly larger prediction error. The robustness of the scheme is also investigated by adding noise to the input beam patterns, and the prediction error is smaller than 0.037 for heavily noisy patterns. This method offers a fast, economic, and robust way to acquire both the mode amplitude and phase information through a single-shot intensity image of HG beams, which will be beneficial to the beam shaping, beam quality evaluation, studies of resonator perturbations, and adaptive optics for resonators of solid-state lasers.

Chemerin induced by Treponema pallidum predicted membrane protein Tp0965 mediates the activation of endothelial cell via MAPK signaling pathway.

Chemerin, a chemoattractant protein, is involved in endothelial dysfunction and vascular inflammation in pathological conditions. In a recent study, we observed the upregulation of chemerin in endothelial cells following in vitro treatment with Treponema pallidum. Here, we investigated the role of chemerin in endothelial cells activation induced by the T. pallidum predicted membrane protein Tp0965. Following stimulation of human umbilical vein endothelial cells (HUVECs) with Tp0965, chemerin and its receptor chemerin receptor 23 (ChemR23) were upregulated, companied with elevated expression of Toll-like receptor 2. Furthermore, chemerin from HUVECs activated endothelial cells via chemerin/ChemR23 signaling in an autocrine/paracrine manner, characterized by upregulated expression of intercellular adhesion molecule 1, E-selectin, and matrix metalloproteinase-2. Activation of endothelial cells depended on the mitogen-activated protein kinase signaling pathway. In addition, Tp0965-induced chemerin promoted THP-1-derived macrophages migration to endothelial cells, also via the chemerin/ChemR23 pathway. The RhoA/ROCK signaling pathway was also involved in THP-1-derived macrophages migration in response to chemerin/ChemR23. Our results highlight the role of Tp0965-induced chemerin in endothelial cells dysfunction, which contributes to the immunopathogenesis of vascular inflammation of syphilis.

Single transcript unit CRISPR 2.0 systems for robust Cas9 and Cas12a mediated plant genome editing.

CRISPR-Cas9 and Cas12a are two powerful genome editing systems. Expression of CRISPR in plants is typically achieved with a mixed dual promoter system, in which Cas protein is expressed by a Pol II promoter and a guide RNA is expressed by a species-specific Pol III promoter such as U6 or U3. To achieve coordinated expression and compact vector packaging, it is desirable to express both CRISPR components under a single Pol II promoter. Previously, we demonstrated a first-generation single transcript unit (STU)-Cas9 system, STU-Cas9-RZ, which is based on hammerhead ribozyme for processing single guide RNAs (sgRNAs). In this study, we developed two new STU-Cas9 systems and one STU-Cas12a system for applications in plants, collectively called the STU CRISPR 2.0 systems. We demonstrated these systems for genome editing in rice with both transient expression and stable transgenesis. The two STU-Cas9 2.0 systems process the sgRNAs with Csy4 ribonuclease and endogenous tRNA processing system respectively. Both STU-Cas9-Csy4 and STU-Cas9-tRNA systems showed more robust genome editing efficiencies than our first-generation STU-Cas9-RZ system and the conventional mixed dual promoter system. We further applied the STU-Cas9-tRNA system to compare two C to T base editing systems based on rAPOBEC1 and PmCDA1 cytidine deaminases. The results suggest STU-based PmCDA1 base editor system is highly efficient in rice. The STU-Cas12a system, based on Cas12a' self-processing of a CRISPR RNA (crRNA) array, was also developed and demonstrated for expression of a single crRNA and four crRNAs. Altogether, our STU CRISPR 2.0 systems further expanded the CRISPR toolbox for plant genome editing and other applications.

Learning to decompose the modes in few-mode fibers with deep convolutional neural network.

We introduce a deep-learning technique to perform complete mode decomposition for few-mode optical fibers for the first time. Our goal is to learn a fast and accurate mapping from near-field beam patterns to the complete mode coefficients, including both modal amplitudes and phases. We train the convolutional neural network with simulated beam patterns and evaluate the network on both the simulated beam data and the real beam data. In simulated beam data testing, the correlation between the reconstructed and the ideal beam patterns can achieve 0.9993 and 0.995 for 3-mode case and 5-mode case, respectively. While in the real 3-mode beam data testing, the average correlation is 0.9912 and the mode decomposition can be potentially performed at 33 Hz frequency on a graphic processing unit, indicating real-time processing ability. The quantitative evaluations demonstrate the superiority of our deep learning-based approach.

Deep learning enabled superfast and accurate M2 evaluation for fiber beams.

We introduce deep learning technique to predict the beam propagation factor M2 of the laser beams emitting from few-mode fiber for the first time, to the best of our knowledge. The deep convolutional neural network (CNN) is trained with paired data of simulated near-field beam patterns and their calculated M2 value, aiming at learning a fast and accurate mapping from the former to the latter. The trained deep CNN can then be utilized to evaluate M2 of the fiber beams from single beam patterns. The results of simulated testing samples have shown that our scheme can achieve an averaged prediction error smaller than 2% even when up to 10 eigenmodes are involved in the fiber. The error becomes slightly larger when heavy noises are added into the input beam patterns but still smaller than 2.5%, which further proves the accuracy and robustness of our method. Furthermore, the M2 estimation takes only about 5 ms for a prepared beam pattern with one forward pass, which can be adopted for real-time M2 determination with only one supporting Charge-Coupled Device (CCD). The experimental results further prove the feasibility of our scheme. Moreover, the method we proposed can be confidently extended to other kinds of beams provided that adequate training samples are accessible. Deep learning paves the way to superfast and accurate M2 evaluation with very low experimental efforts.

Ultraviolet-enhanced supercontinuum generation with a mode-locked Yb-doped fiber laser operating in dissipative-soliton-resonance region.

We experimentally demonstrate an all-fiber, ultraviolet-enhanced, supercontinuum generation in a specifically designed seven-core photonic crystal fiber pumped by a picosecond Yb-doped master oscillator power amplifier (MOPA). The MOPA source is seeded by a giant-chirped Yb-doped mode-locked fiber laser operating in the dissipative-soliton-resonance (DSR) region. The DSR is achieved by using a nonlinear optical loop mirror (NOLM) with a fundamental repetition rate of 4.5 MHz and a central wavelength of 1035 nm. An extremely wide optical spectrum spanning from 350 nm to 2400 nm is obtained with a total output power of 6.86 W.

Morin inhibits proliferation and self-renewal of CD133+ melanoma cells by upregulating miR-216a.

Melanoma is one of the most malignant skin tumors with high mortality rate. Morin has been reported to treat several cancers. However, whether or how Morin affects melanoma progression is still poorly understood. Either Morin treatment or miR-216a overexpression reduced cell viability, sphere formation ability and expressions of stem cell marker genes CD20, CD44, CD133 and Wnt-3A. MiR-216a was induced by Morin treatment in CD133+ melanoma cells. Melanoma xenograft model treated by Morin showed reduced tumor size, weight as well as expressions of stemness markers and Wnt-3A. Inhibition of the stemness marker gene expressions in CD133+ melanoma cells is mediated by downregulating Wnt-3A through miR-216a. MiR-216a and Wnt-3A may potentially serve as clinical biomarkers of melanoma, and Morin may contribute to the treatment of melanoma.

Genome-Wide Identification, Expression, and Functional Analysis of the Alkaline/Neutral Invertase Gene Family in Pepper.

Alkaline/neutral invertase (NINV) proteins irreversibly cleave sucrose into fructose and glucose, and play important roles in carbohydrate metabolism and plant development. To investigate the role of NINVs in the development of pepper fruits, seven NINV genes (CaNINV1-7) were identified. Phylogenetic analysis revealed that the CaNINV family could be divided into α and ß groups. CaNINV1-6 had typical conserved regions and similar protein structures to the NINVs of other plants, while CaNINV7 lacked amino acid sequences at the C-terminus and N-terminus ends. An expression analysis of the CaNINV genes in different tissues demonstrated that CaNINV5 is the dominant NINV in all the examined tissues (root, stem, leaf, bud, flower, and developmental pepper fruits stage). Notably, the expression of CaNINV5 was found to gradually increase at the pre-breaker stages, followed by a decrease at the breaker stages, while it maintained a low level at the post-breaker stages. Furthermore, the invertase activity of CaNINV5 was identified by functional complementation of the invertase-deficient yeast strain SEY2102, and the optimum pH of CaNINV5 was found to be ~7.5. The gene expression and enzymatic activity of CaNINV5 suggest that it might be the main NINV enzyme for hydrolysis of sucrose during pepper fruit development.

Facile functionalization at the C4 position of pyrimidine nucleosides via amide group activation with (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP) and biological evaluations of the products.

Reactions of O-t-butyldimethylsilyl-protected thymidine, 2'-deoxyuridine, and 3'-azidothymidine (AZT) with (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP) leads to activation of the C4 amide carbonyl by formation of putative O4-(benzotriazol-1-yl) derivatives. Subsequent substitution with alkyl and aryl amines, thiols, and alcohols leads to facile functionalization at this position. Reactions with amines and thiols were conducted either as a two-step, one-pot transformation, or as a one-step conversion. Reactions with alcohols were conducted as two-step, one-pot transformations. In the course of these investigations, the formation of 1-(4-pyrimidinyl)-1H-benzotriazole-3-oxide derivatives from the pyrimidine nucleosides was identified. However, these too underwent conversion to the desired products. Products obtained from AZT were converted to the 3'-amino derivatives by catalytic reduction. All products were assayed for their abilities to inhibit cancer cell proliferation and for antiviral activities. Many were seen to be active against HIV-1 and HIV-2, and one was active against herpes simplex virus-1 (HSV-1).

Correction: Facile functionalization at the C4 position of pyrimidine nucleosides via amide group activation with (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP) and biological evaluations of the products.

Correction for 'Facile functionalization at the C4 position of pyrimidine nucleosides via amide group activation with (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP) and biological evaluations of the products' by Hari K. Akula, et al., Org. Biomol. Chem., 2017, DOI: 10.1039/c6ob02334g.

Efficacy and Safety of Targeted High-Intensity Medium-Band (304-312 nm) Ultraviolet B Light in Pediatric Vitiligo.

BACKGROUND/OBJECTIVES: Phototherapy is a commonly used treatment for vitiligo that has demonstrated safety and efficacy. High-intensity targeted ultraviolet B (UVB) light (304-312 nm) delivered using a phototherapy device is a useful therapeutic option because it can induce repigmentation in a short time without global exposure to radiation, but information regarding this device in children is limited. METHODS: We performed a retrospective analysis of 95 patches of vitiligo in 27 children treated using a targeted phototherapy device. Phototherapy was administered twice a week. RESULTS: After the first 10 treatment sessions, 82 (86.3%) patches demonstrated some repigmentation and 36.8% achieved 50% or more repigmentation. After a mean of 20.4 treatment sessions, 86 patches (90%) demonstrated some repigmentation and 53.7% achieved 50% or more repigmentation. Responses varied depending on the anatomic location of the lesions. Better responses were usually observed on the face and trunk, whereas the extremities typically showed little response. Repigmentation was better in patients with active vitiligo than in those with stable vitiligo, with responses better with a disease duration of 1 year or less than in those with a duration of more than 1 year. There was no statistically significant difference in repigmentation between those with segmental and generalized vitiligo. The only short-term local side effect was mild erythema that required a decrease in dosage in six patients. CONCLUSION: Targeted high-intensity medium-band UVB phototherapy alone can produce clinical improvement in pediatric vitiligo and is well tolerated.

Mutations in POFUT1, encoding protein O-fucosyltransferase 1, cause generalized Dowling-Degos disease.

Dowling-Degos disease (DDD), or reticular pigmented anomaly of the flexures, is a type of rare autosomal-dominant genodermatosis characterized by reticular hyperpigmentation and hypopigmentation of the flexures, such as the neck, axilla, and areas below the breasts and groin, and shows considerable heterogeneity. Loss-of-function mutations of keratin 5 (KRT5) have been identified in DDD individuals. In this study, we collected DNA samples from a large Chinese family affected by generalized DDD and found no mutation of KRT5. We performed a genome-wide linkage analysis of this family and mapped generalized DDD to a region between rs1293713 and rs244123 on chromosome 20 [corrected]. By exome sequencing, we identified nonsense mutation c.430G>T (p.Glu144(∗)) in POFUT1, which encodes protein O-fucosyltransferase 1, in the family. Study of an additional generalized DDD individual revealed the heterozygous deletion mutation c.482delA (p.Lys161Serfs(∗)42) in POFUT1. Knockdown of POFUT1 reduces the expression of NOTCH1, NOTCH2, HES1, and KRT5 in HaCaT cells. Using zebrafish, we showed that pofut1 is expressed in the skin and other organs. Morpholino knockdown of pofut1 in zebrafish produced a phenotype characteristic of hypopigmentation at 48 hr postfertilization (hpf) and abnormal melanin distribution at 72 hpf, replicating the clinical phenotype observed in our DDD individuals. At 48 and 72 hpf, tyrosinase activities decreased by 33% and 45%, respectively, and melanin protein contents decreased by 20% and 25%, respectively. Our findings demonstrate that POFUT1 mutations cause generalized DDD. These results strongly suggest that the protein product of POFUT1 plays a significant and conserved role in melanin synthesis and transport.

A novel bis(pinacolato)diboron-mediated N-O bond deoxygenative route to C6 benzotriazolyl purine nucleoside derivatives.

Reaction of amide bonds in t-butyldimethylsilyl-protected inosine, 2'-deoxyinosine, guanosine, 2'-deoxyguanosine, and 2-phenylinosine with commercially available peptide-coupling agents (benzotriazol-1H-yloxy)tris(dimethylaminophosphonium) hexafluorophosphate (BOP), (6-chloro-benzotriazol-1H-yloxy)trispyrrolidinophosphonium hexafluorophosphate (PyClocK), and (7-azabenzotriazol-1H-yloxy)trispyrrolidinophosphonium hexafluorophospate (PyAOP) gave the corresponding O(6)-(benzotriazol-1-yl) nucleoside analogues containing a C-O-N bond. Upon exposure to bis(pinacolato)diboron and base, the O(6)-(benzotriazol-1-yl) and O(6)-(6-chlorobenzotriazol-1-yl) purine nucleoside derivatives obtained from BOP and PyClocK, respectively, underwent N-O bond reduction and C-N bond formation, leading to the corresponding C6 benzotriazolyl purine nucleoside analogues. In contrast, the 7-azabenzotriazolyloxy purine nucleoside derivatives did not undergo efficient deoxygenation, but gave unsymmetrical nucleoside dimers instead. This is consistent with a prior report on the slow reduction of 1-hydroxy-1H-4-aza and 1-hydroxy-1H-7-azabenzotriazoles. Because of the limited number of commercial benzotriazole-based peptide coupling agents, and to show the applicability of the method when such coupling agents are unavailable, 1-hydroxy-1H-5,6-dichlorobenzotriazole was synthesized. Using this compound, silyl-protected inosine and 2'-deoxyinosine were converted to the O(6)-(5,6-dichlorobenzotriazol-1-yl) derivatives via in situ amide activation with PyBroP. The O(6)-(5,6-dichlorobenzotriazol-1-yl) purine nucleosides so obtained also underwent smooth reduction to afford the corresponding C6 5,6-dichlorobenzotriazolyl purine nucleoside derivatives. A total of 13 examples were studied with successful reactions occurring in 11 cases (the azabenzotriazole derivatives, mentioned above, being the only unreactive entities). To understand whether these reactions are intra or intermolecular processes, a crossover experiment was conducted. The results of this experiment as well as those from reactions conducted in the absence of bis(pinacolato)diboron and in the presence of water indicate that detachment of the benzotriazoloxy group from the nucleoside likely occurs, followed by reduction, and reattachment of the ensuing benzotriazole, leading to products.