Early Stages Of Development Research Articles

Reproducible, Scale-Up Production of Human Brain Organoids (HBOs) on a Pillar Plate Platform via Spheroid Transfer.

Human brain organoids (HBOs) derived from pluripotent stem cells hold great potential for disease modeling and high-throughput compound screening, given their structural and functional resemblance to fetal brain tissues. These organoids can mimic early stages of brain development, offering a valuable in vitro model to study both normal and disordered neurodevelopment. However, current methods of generating HBOs are often low throughput and variable in organoid differentiation and involve lengthy, labor-intensive processes, limiting their broader application in both academic and industrial research. Key challenges include high costs of growth factors, variability in organoid size and function, suboptimal maturation, and manual handling that reduces throughput. Here, we present a standard operating procedure (SOP) for the scalable production of HBOs using a novel pillar plate system that simplifies the spheroid transfer process and allows miniature organoid culture. This method enables the reproducible generation of HBOs without the need for extensive manual intervention, providing a streamlined solution for high-throughput screening (HTS). The resulting assay-ready pillar plate with HBOs is optimized for compound testing, in situ staining, and analysis, offering an efficient platform to advance neurodevelopmental research and therapeutic screening.

A Fresh Look at Celery Collenchyma and Parenchyma Cell Walls Through a Combination of Biochemical, Histochemical, and Transcriptomic Analyses

Celery (Apium graveolens) can be considered as a model plant for studying pectin-enriched primary cell walls. In addition to parenchyma cells with xyloglucan-deficient walls, celery petioles contain collenchyma, a mechanical tissue with thickened cell walls of similar composition. This study presents a comprehensive analysis of these tissues at both early and late developmental stages, integrating data on polysaccharide yield, composition, localization, and transcriptome analysis. Our results reveal that young collenchyma walls possess distinct polysaccharide compositions, including higher levels of rhamnogalacturonan I (RG-I), branched galactans, esterified homogalacturonan, and xyloglucan, compared to parenchyma cells. A significant number of genes encoding proteins involved in pectin methylesterification and acetylation were upregulated in young collenchyma. Different gene isoforms encoding glycosyltransferases involved in RG-I biosynthesis were activated in both collenchyma and parenchyma, suggesting potential variations in RG-I structure and function across different primary cell walls. We identified a set of potential glycosyltransferases involved in RG-I biosynthesis in collenchyma and proposed synthase complexes for heteromannan and heteroxylan. The transcriptome data not only confirmed known biochemical traits of celery cell walls but also provided deeper insights into the peculiarities of cell wall polysaccharide metabolism, thereby helping to narrow down candidate genes for further molecular genetic studies.

Brief exposure to (-) THC affects zebrafish embryonic locomotion with effects that persist into the next generation

Cannabis is one of the most widely used drugs, and yet an understanding of its impact on the human brain and body is inconclusive. Medicinal and recreational use of cannabis has increased in the last decade with a concomitant increase in use by pregnant women. The major psychoactive compound in cannabis, Δ9-tetrahydrocannabinol (THC), exists in different isomers, with the (-) trans isomer most common. Prenatal exposure to THC can alter neural and behavioral development, but it is unknown how exposure to (-) trans-THC ((-)THC) during very early stages of development impacts fetal growth and movement, and whether effects persist to adulthood, or into the next generation. Here we exposed zebrafish (Danio rerio) to a single exposure of (-)THC (0.001 mg/L (3.2 nM) to 20 mg/L (63.6 µM), for 5 h) during gastrulation (5.25 hpf to 10.75 hpf) when key neurons involved in locomotion such as the primary motor neurons and Mauthner cell first appear. We then examined the impact on embryo morphology and locomotion, adult behavior, and locomotion in the next (F1) generation. Embryos treated with (-)THC experienced changes in morphology, were shorter in length and experienced altered hatching and survival. Spontaneous coiling of 1 dpf embryos was reduced, swimming after touch-evoked responses was reduced and basal swimming in 5 dpf larvae was also reduced. Adult zebrafish tested in the open field test and novel object approach test demonstrated no differences in locomotion, anxiety-like behavior, nor boldness, compared to controls. The (-)THC F1 generation embryos at 1 dpf showed reduced coiling activity, while swimming after touch-evoked responses was reduced in 2 dpf animals but basal swimming at 5 dpf remained similar to controls. Taken together, exposure to (-)THC only once for 5 h during gastrulation has a significant impact on locomotion in embryos and larvae, a minimal impact on adult behavior, and effects that persist into the next generation.

Isolation and Characterization of GPAT3 Gene from Jojoba Plant and its Inferior Early Diagnosis of Sex.

<b>Background and Objective:</b> In jojoba plants, the sex is usually difficult to identify, especially before flowering and during the very early stages of development. This stage is expected to facilitate breeding programs and adopt an invention and approach to isolate the GPAT gene identified between males and females: The study aimed at early diagnosis of sex in jojoba by sequence characterized by GPAT gene of sex-determining by simplex PCR. To prove the existence of the GPAT gene in male jojoba plants which may be the sex determination and identification in all plant systems. <b>Materials and Methods:</b> Initially, different primers were selected for the sex determination of jojoba samples using PCR-based amplification. The primers that can produce distinct DNA bands in males, not in females were selected for further experiments. The amplification of a male-specific GPAT marker situated in the sex determination region was amplified using specific primers. The newly designed GPAT primers flank region. <b>Results:</b> For the first time, separation and identified of the GPAT gene sequence of jojoba was done. The novel method represents a breakthrough in the sex determination of jojoba to identify sex at early developmental stages. This work provides a potentially useful diagnostic for determining sex in jojoba species. In this report, a breakthrough in the methodology for determining the sex of jojoba has been made. The amplified regions of the GPAT gene closely matched with sequences of GPAT in papaya and humans. <b>Conclusion:</b> The authors make an interesting finding by targeting the sequences in the GPAT gene and the final conclusion that PCR as a simple, rapid and reliable technique can complement and confirm sex by using specific primers pair according to our invention.

The Potential of Arboreal Tiger Beetle (<em>Derocrania scitiscabra</em> Walker) as a Natural Enemy for the Control of Fall Armyworm (<em>Spodoptera frugiperda</em> JE Smith)

Purpose: The fall armyworm, Spodoptera frugiperda, is a serious pest of maize, sugarcane, and other crops in Sri Lanka. Natural predators and parasitoids are considered the best methods to control this insect pest. The present study investigates the possibility of using an endemic tiger beetle, Derocrania scitiscabra, as a natural predator for the larval stages of S. frugiperda.Research Method: The feeding preferences of D. scitiscabra to live prey versus dead prey, live prey types including different instar stages of S. frugiperda were investigated in the laboratory using choice tests. Fresh minced meat was used as dead prey, while red ants, earthworms and the six larval instar stages of S. frugiperda were used as live prey.Findings: Red ants were the most preferred prey type of D. scitiscabra, and dead prey, earthworms and mature S. frugiperda larvae were not consumed. Early larval instar stages of S. frugiperda were selected as prey, and the beetle showed a high feeding preference for the second larval instar stage. This feeding preference was observed irrespective of whether red ants were present or absent in the same environment. D. scitiscabra may have selected the second larval instars of S. frugiperda due to their small size, high prey density, mobility, and being devoid of injury.Research Limitations: The tests were conducted under laboratory conditions in insectary facilities. However, field investigations are essential to understand the ecological dynamics that affect insect behavior and survival.Originality/value: An endemic beetle is introduced to control S. frugiperda infestations in their early stages of development. The finding may provide an environmentally safe and economically beneficial method to control S. frugiperda

Venlafaxine induces Teratogenesis and alters SHH Gene Expression and Protein Biochemistry of Developing Gallus sp. Embryos

The use of antidepressant drugs during pregnancy is increasing globally. SNRIs and SSRIs are most widely used for treating panic disorders. Venlafaxine is an antidepressant that inhibits serotonin and norepinephrine reuptake. Given the increasing prevalence of antidepressant use during pregnancy, Venlafaxine exposure during the early stages of development could lead to changes in protein dynamics and disrupt essential gene pathways, raising concerns about the potential teratogenic effects of antidepressant exposure during pregnancy. This study explores the developmental impact of Venlafaxine, a commonly prescribed serotonin-norepinephrine reuptake inhibitor (SNRI), on protein biochemistry and gene expression in the developing Gallus gallus domesticus embryos. Significant changes in protein profiles were observed among control and Venlafaxine-treated groups. Sonic Hedgehog (SHH) gene, a key regulator of embryonic patterning and organogenesis, specifically neural tube formation, and limb development, is known for its crucial role in embryonic development. qRT-PCR analysis of Venlafaxine-treated embryos showed changes in SHH gene expression suggesting that Venlafaxine may target SHH gene expression, and potentially alter signalling pathways crucial for normal embryogenesis. However, detailed studies are needed to understand the long-term consequences of prenatal and foetal antidepressant exposure on embryonic growth and development. These changes may lead to abnormal growth patterns or congenital defects, emphasizing the need for caution when prescribing Venlafaxine during pregnancy. Keywords: Antidepressants, Venlafaxine, SNRI, Gallus gallus domesticus, Sonic Hedgehog (SHH), Protein Biochemistry, qRT-PCR

Geroscience in heart failure: the search for therapeutic targets in the shared pathobiology of human aging and heart failure

Age is a major risk factor for heart failure, but one that has been historically viewed as non-modifiable. Emerging evidence suggests that the biology of aging is malleable, and can potentially be intervened upon to treat age-associated chronic diseases, such as heart failure. While aging biology represents a new frontier for therapeutic target discovery in heart failure, the challenges of translating Geroscience research to the clinic are multifold. In this review, we propose a strategy that prioritizes initial target discovery in human biology. We review the rationale for starting with human omics, which has generated important insights into the shared (patho)biology of human aging and heart failure. We then discuss how this knowledge can be leveraged to identify the mechanisms of aging biology most relevant to heart failure. Lastly, we provide examples of how this human-first Geroscience approach, when paired with rigorous functional assessments in preclinical models, is leading to early-stage clinical development of gerotherapeutic approaches for heart failure.

Application of the OSNA Technique (One-Step Nucleic Acid Amplification Test) in Breast Cancer

Breast cancer is one of the most common cancers diagnosed in both countries with high and low levels of socio-academic development. Routine, regular screening tests being introduced in an increasing number of countries make it possible to detect breast cancer at an early stage of development, as a result of which the trend in the incidence of metastatic breast cancer has been decreasing in recent years. The latest guidelines for the treatment of this tumor do not recommend axillary dissection, which limits the need for rapid assessment of the nodes during surgery. Regardless of the progression of the disease, lymph node biopsy and their analysis is one of the most common diagnostic methods for detecting metastases. Systems using one-step amplification of nucleic acids have been present in the diagnosis of breast cancer for nearly 20 years. The one-step nucleic acid amplification (OSNA) test semi-quantitatively detects the number of cytokeratin 19 mRNA copies, a well-known tumor marker, which can be used to infer the presence of metastases in non-sentinel lymph nodes (SLN). Aim: OSNA is a widely used molecular method for SLN, intra-, or postoperative analysis. Its high accuracy has been proved over the years in clinical use. In this review, we checked current state of this technology and compared it to its competitors in the field of breast cancer diagnosis in the era of Axillary Lymph Nodes Dissection (ALND) importance decrease with intention to foresee its further potential use. Objectives: To evaluate OSNA current place in breast cancer diagnosis and treatment we compared OSNA to other lymph node assessing methods. We based our review on original articles and metanalyses published in the last decade. The research was conducted with PubMed, Science Direct, Google Scholar, and NCBI databases. The collected data allowed us to assess the accuracy of OSNA, its cost effectiveness, and its application in other cancers. Results: Regardless of the progression of the disease, a lymph node biopsy and its analysis constitutes one of the most common diagnostic methods for detecting metastases. The OSNA method is characterized by high sensitivity and specificity, and its predictive value has been confirmed by many studies over the years. While its cost effectiveness is still a matter of discussion, this method has been tested more thoroughly than other new lymph nodes assessing technologies. Conclusions: Despite the emergence of competing methods, this test is still widely used as a routine intraoperative examination of lymph nodes. Research carried out in recent years has proved its effectiveness in the diagnosis of other cancers, in the research field, and as a provider of additional data for prognosis improvement.

Framework Using Multicriteria Analysis for Evaluating the Risk of Musculoskeletal Disorders

This study includes musculoskeletal disorder (MSD) risk evaluation based on the IMU sensor data gathered from patient-lifting movement performed by healthcare specialists. This is a continuation of previous research focusing on a novel multicriteria statistical model integrating experimental and large-scale statistical datasets. The proposed model estimates MSD probabilities over 5, 10, and 15 years for the neck (0.537 ± 0.156), shoulder (0.449 ± 0.084), and elbows (0.277 ± 0.221). The model enables individual risk profiling, influenced by dynamic parameters that can reduce the long-term risk by up to 70.49%. The model is in its early development stages, i.e., it is the proof of concept that offers a new approach to assessing MSD risk at work using motion tracking data in combination with statistics. Further studies with larger sample sizes and validated criterion weights are needed to refine and validate this approach.

A Simple Machine Learning-Based Quantitative Structure–Activity Relationship Model for Predicting pIC50 Inhibition Values of FLT3 Tyrosine Kinase

Background/Objectives: Acute myeloid leukemia (AML) presents significant therapeutic challenges, particularly in cases driven by mutations in the FLT3 tyrosine kinase. This study aimed to develop a robust and user-friendly machine learning-based quantitative structure–activity relationship (QSAR) model to predict the inhibitory potency (pIC50 values) of FLT3 inhibitors, addressing the limitations of previous models in dataset size, diversity, and predictive accuracy. Methods: Using a dataset which was 14 times larger than those employed in prior studies (1350 compounds with 1269 molecular descriptors), we trained a random forest regressor, chosen due to its superior predictive performance and resistance to overfitting. Rigorous internal validation via leave-one-out and 10-fold cross-validation yielded Q2 values of 0.926 and 0.922, respectively, while external validation on 270 independent compounds resulted in an R2 value of 0.941 with a standard deviation of 0.237. Results: Key molecular descriptors influencing the inhibitor potency were identified, thereby improving the interpretability of structural requirements. Additionally, a user-friendly computational tool was developed to enable rapid prediction of pIC50 values and facilitate ligand-based virtual screening, leading to the identification of promising FLT3 inhibitors. Conclusions: These results represent a significant advancement in the field of FLT3 inhibitor discovery, offering a reliable, practical, and efficient approach for early-stage drug development, potentially accelerating the creation of targeted therapies for AML.

Long-term nitrogen fertilization alters the partitioning of amino acids between citrus leaves and fruits

IntroductionThe growth of evergreen fruit trees is influenced by the interaction of soil nitrogen (N) and leaf amino acid contents. However, information on free amino acid contents in leaves of fruiting and non-fruiting branches during long-term N fertilizer application remains scarce.MethodsHere, a four-year field experiment (2018-2021) in a citrus orchard revealed consistently lower total N and amino acid contents in leaves of fruiting compared to non-fruiting branches.Results and discussionAppropriate N fertilizer application increased free amino acid and total N contents in leaves of both types of branches and fruits, but excessive amounts led to decreases. Correlation analysis showed that, in the early stage of fruit development, leaves on both types of branches can meet the N requirements of the fruit (R²=0.77 for fruiting, R²=0.82 for non-fruiting). As fruits entered the swelling stage, a significant positive correlation emerged between fruiting branch leaves and fruit total N content (R²=0.68), while the R² for leaves on non-fruiting branches dropped to 0.47, indicating a shift in N supply towards leaves on fruiting branches. Proline and arginine are the most abundant amino acids in these leaves. At fruit maturity, these amino acids account for more than half of the total amino acids in the fruit (29.0% for proline and 22.2% for arginine), highlighting their crucial role in fruit development. Further research is needed to investigate amino acid transport and distribution mechanisms between citrus leaves and fruits.

Early Initiation of Bundle Sheath Cells During Leaf Development as Visualised by SCARECROW Expression in Dicotyledonous C4 Plants.

The C4 type of dicotyledonous plants exhibit a higher density of reticulate veins than the C3 type, with a nearly 1:1 ratio of mesophyll cells (MCs) to bundle sheath cells (BSCs). To understand how this C4-type cell pattern is formed, we identified two SCARECROW (SCR) genes in C4 Flaveria bidentis, FbSCR1 and FbSCR2, that fully or partially complement the endodermal cell layer-defective phenotype of Arabidopsis scr mutant. We then created FbSCRs promoter β-glucuronidase reporter (GUS) lines of F. bidentis, which showed GUS expression in BSCs and their progenitor cells. The GUS expression pattern in F. bidentis transformants and comparison with the closely related C3-type Flaveria pringlei revealed that higher-order veins were initiated in the early leaf developmental stage. Treatment with an auxin polarity transport inhibitor decreased the MC area and led to vein formation without free ends, resulting in the formation of BSCs in positions adjacent to other BSCs. However, BSC differentiation was not affected, as evidenced by BSC specific FbSCR1 expression and RuBisCO accumulation. These results indicate that polar auxin transport is important for MC proliferation and/or differentiation, which leads to the formation of a C4-type cell pattern in which MCs and BSCs are equally adjacent.

Recent advances and application of liquid chromatography in pharmaceutical industry

Liquid chromatography (LC) and its associated techniques are essential in the pharmaceutical industry for optimizing drug formulations, ensuring product quality, and meeting regulatory standards. Thin Layer Chromatography (TLC) is widely used for rapid screening and chiral separations in early-stage development due to its simplicity and cost-effectiveness. High-Performance Liquid Chromatography (HPLC) remains the gold standard for routine analysis, offering high resolution and reproducibility for complex sample analysis and quantification of active pharmaceutical ingredients (APIs). Ultra-Performance Liquid Chromatography (UPLC) builds on HPLC, providing faster analysis, higher sensitivity, and greater efficiency, making it ideal for high-throughput testing. Supercritical Fluid Chromatography (SFC) is increasingly used for separating thermally labile and polar compounds, offering advantages in solvent usage and analysis time. This review will discuss the evolution of these chromatographic techniques and their critical role in optimizing pharmaceutical processes, ensuring product quality, and facilitating regulatory compliance throughout the drug development lifecycle.

Enhancing Electrocatalytic Activity Through Targeted Local Electrolyte Micro‐Environment

AbstractThe local electrolyte micro‐environment surrounding the catalyst reaction center, including critical factors such as pH, reactant concentration, and electric field, plays a decisive role in electrocatalytic reactions such as water splitting. Recently, this topic has garnered significant attention due to its potential to significantly enhance catalytic performance. While various strategies to optimize electrocatalytic processes have been explored, deliberate control over the micro‐environment and the fundamental principles guiding these local adjustments remain in their early stages of development. This review provides a comprehensive examination of key efforts aimed at designing and tailoring localized micro‐environments to improve electrocatalytic performance. It discusses advances in micro‐environmental design, methodologies for evaluating micro‐environmental shifts, and the mechanistic insights driving these developments. Additionally, this review highlights existing challenges and prospective industrial applications of localized micro‐environment strategies. By offering a detailed analysis of recent developments, this review aims to equip researchers with practical knowledge on controlling micro‐environments, thereby accelerating progress toward practical real‐world applications in electrocatalytic processes.

Genome-wide association study of varenicline-aided smoking cessation.

Varenicline is an α4β2 nicotinic acetylcholine receptor partial agonist with the highest therapeutic efficacy of any pharmacological smoking cessation aid and a 12-month cessation rate of 26%. Genetic variation may be associated with varenicline response, but to date no genome-wide association studies of varenicline response have been published. In this study, we investigated the genetic contribution to varenicline effectiveness using two electronic health record-derived phenotypes. We defined short-term varenicline effectiveness (SVE) and long-term varenicline effectiveness (LVE) by assessing smoking status at 3 and 12 months, respectively, after initiating varenicline treatment. In Stage 1, comprising five European cohort studies, we tested genome-wide associations with SVE (1,405 cases, 2,074 controls) and LVE (1,576 cases, 2,555 controls), defining sentinel variants (the most strongly associated variant within 1 megabase) with p-value <5×10-6 to follow up in Stage 2. In Stage 2, we tested association between sentinel variants and comparable smoking cessation endpoints in varenicline randomised controlled trials. We subsequently meta-analysed Stages 1 and 2. No variants reached genome-wide significance in the meta-analysis. In Stage 1, 10 sentinel variants were associated with SVE and five with LVE at a suggestive significance threshold (p-value <5×10-6); none of these sentinels were previously implicated in varenicline-aided smoking cessation or in genetic studies of smoking behaviour. We provide initial insights into the biological underpinnings of varenicline-aided smoking cessation, through implicating genes involved in various processes, including gene expression, cilium assembly and early-stage development. Leveraging electronic health records, we undertook the largest genetic study of varenicline-aided smoking cessation to date, and the only such study to test genome-wide associations. We showed distinct genetic variants associated (p-value <5×10-6) with varenicline-aided smoking cessation which implicate diverse cellular functions, including transcriptional regulation, RNA modification and cilium assembly. These provide insights which, if independently corroborated, will improve understanding of varenicline response. The growing availability of biobank resources with genetic and varenicline response data will provide future opportunities for larger studies using the approach we developed.

Chemometric Methods—A Valuable Tool for Investigating the Interactions Between Antifungal Drugs (Including Antifungal Antibiotics) and Food

Background/Objectives: Developing antifungal drugs with lower potential for interactions with food may help to optimize treatment and reduce the risk of antimicrobial resistance. Chemometrics uses statistical and mathematical methods to analyze multivariate chemical data, enabling the identification of key correlations and simplifying data interpretation. We used the partial least squares (PLS) approach to explore the correlations between various characteristics of oral antifungal drugs (including antifungal antibiotics) and dietary interventions, aiming to identify patterns that could inform the optimization of antifungal therapy. Methods: We analyzed 15 oral antifungal drugs, including azoles (8), antifungal antibiotics (4), antifungal antimetabolites (1), squalene epoxidase inhibitors (1), and glucan synthase inhibitors (1). The input dataset comprised information from published clinical trials, chemical records, and calculations. We constructed PLS models with changes in the pharmacokinetic parameters (∆AUC, area under the curve; ∆Cmax, maximum drug concentration; and ∆Tmax, time to reach maximum drug concentration) after dietary intervention as the response parameters and eight groups of molecular descriptors (M1–M8) as the predictor parameters. We performed separate analyses for the different nutritional interventions. Results: In the final PLS model with food as an intervention, we effectively reduced the dimensionality of the dataset while retaining a substantial percentage of the original information (variance), as significant components explained 69.8% and 17.5% of the predictor and response parameter variances, respectively. The PLS model was significant because its components met the cross-validation criteria. We obtained six significant positive and negative correlations between the descriptors related to atoms and the postprandial ∆Tmax. Conclusions: The PLS method is valuable for investigating interactions between antifungal drugs (including antifungal antibiotics) and food. The correlations obtained can be used in drug modeling to predict interactions with dietary interventions based on the antifungal drug’s chemical structure. Incorporating chemometric techniques into the early drug development stages could facilitate the design of antifungal antibiotics and other antifungal agents with optimized absorption in the presence of dietary components.

Systemic regulation of retinal medium-chain fatty acid oxidation repletes TCA cycle flux in oxygen-induced retinopathy

Activation of anaplerosis takes away glutamine from the biosynthetic pathways to the energy-producing TCA cycle. Especially, induction of hyperoxia driven anaplerosis in neurovascular tissues such as the retina during early stages of development could deplete biosynthetic precursors from newly proliferating endothelial cells impeding physiological angiogenesis and leading to vasoobliteration. Using an oxygen-induced retinopathy (OIR) mouse model, we investigated the metabolic differences between OIR-resistant BALB/cByJ and OIR susceptible C57BL/6J strains at system levels to understand the molecular underpinnings that potentially contribute to hyperoxia-induced vascular abnormalities in the neural retina. Our systems level in vivo RNA-seq, proteomics, and lipidomic profiling and ex-vivo retinal explant studies show that the medium-chain fatty acids serves as an alternative source to feed the TCA cycle. Our findings strongly implicate that medium-chain fatty acids could suppress glutamine-fueled anaplerosis and ameliorate hyperoxia-induced vascular abnormalities in conditions such as retinopathy of prematurity.

Temperature Regulates Astroglia Morphogenesis Through Thermosensory Circuitry in Caenorhabditis elegans.

Astrocytes are the most abundant type of macroglia in the brain and play crucial roles in regulating neural development and functions. The diverse functions of astrocytes are largely determined by their morphology, which is regulated by genetic and environmental factors. However, whether and how the astrocyte morphology is affected by temperature remains largely unknown. Here we discovered that elevated cultivation temperature (26°C) stimulates Caenorhabditis elegans ventral CEPsh glia endfoot extension during early developmental stages. This extension depends on the activation of glutamate AWC neurons, which inhibit the postsynaptic cholinergic AIY interneurons through glutamate-gated chloride channels, GLC-3 and GLC-4. In responding to the thermosensory signal, the guanyl-nucleotide exchange factor EPHX-1 and Rho GTPase CDC-42/Cdc42 in the glia facilitate the endfoot extension via F-actin assembly. This study elucidates the significant role of thermosensory circuitry in glia morphogenesis and the underlying molecular mechanism.

Molecular phylogeny and systematic revision of the Brazilian species of Mastigoproctus Pocock, 1894 (Arachnida: Uropygi: Mastigoproctinae).

Uropygi is an order of arachnids commonly known as vinegaroons or whip-scorpions. So far, two genera are known to occur in Brazil: Thelyphonellus Pocock, 1894 and Mastigoproctus Pocock, 1894. We examined the morphology of 182 specimens of Brazilian Mastigoproctus and sequenced 42 specimens for phylogenetic analyses, using mitochondrial and nuclear molecular markers. Phylogenetic inference was performed under maximum parsimony, maximum likelihood and Bayesian inference. Our results suggest that the Brazilian species previously included in Mastigoproctus represent two different genera, with the following species and synonymies: the revalidated Amauromastigon Mello-Leitão, 1931, composed of A. maximus (Tarnani, 1889), comb. nov. (=Mastigoproctus annectens Werner, 1916, M. butleri Pocock, 1894 and M. perditus Mello-Leitão, 1931), and Heptatarsus gen. nov., composed of H. brasilianus (Koch, 1843), comb. nov. (=Mastigoprotus minensis Mello-Leitão, 1931) and H. custodioi sp. nov. Also, we urge caution when using certain morphological characters when describing uropygid taxa based on specimens in early developmental stages. ZooBank: urn:lsid:zoobank.org:pub:9EF06715-2BA1-4616-A801-2239DBE3DAB4.

Effect of Cdk1 gene disruption on cell cycle progression in newt cells.

Cyclin-dependent kinases (CDKs) are key regulators of cell cycle progression, in conjunction with cyclins. The cyclin-CDK system is highly conserved among eukaryotes, and CDK1 is considered essential for progression through the M phase. However, the extent to which cell cycle progression depends on CDK1 varies between cell types. Therefore, a range of cell types must be analyzed to comprehensively elucidate the role of CDK1. Cdk1-knockout mice exhibit lethality at an early developmental stage, specifically before the differentiation of various cell types. The aim of the present study was to characterize the effects of CDK1 deficiency in amphibian newts. Cdk1 was disrupted by injecting fertilized newt eggs with CRISPR/Cas9, and the resulting effects on embryonic development and cell proliferation were then evaluated. In both wild-type and Cdk1-crispant newt embryos, CDK1 protein was either stored in the egg until late embryogenesis or potentially derived from maternal mRNA, which may also be stored during this period. The embryos survived to the hatching stage, during which the cells responsible for forming the basic organs differentiated. To further characterize the long-term effects of Cdk1 knockout, parabiosis experiments were conducted using wild-type embryos and Cdk1 crispants. The results suggested that an endocycle occurred in the crispant larvae, as evidenced by increases in the size of several types of cells. It is anticipated that studies using newts will provide further insights into the role of Cdk1 in regulating the cell cycle.