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1.
Cell Rep ; 43(4): 114095, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38613787

ABSTRACT

Interferon (IFN) contributes to the host's antiviral response by inducing IFN-stimulated genes (ISGs). However, their functional targets and the mechanism of action remain elusive. Here, we report that one such ISG, TRIM21, interacts with and degrades the TRPV2 channel in myeloid cells, reducing its expression and providing host protection against viral infections. Moreover, viral infection upregulates TRIM21 in paracrine and autocrine manners, downregulating TRPV2 in neighboring cells to prevent viral spread to uninfected cells. Consistently, the Trim21-/- mice are more susceptible to HSV-1 and VSV infection than the Trim21+/+ littermates, in which viral susceptibility is rescued by inhibition or deletion of TRPV2. Mechanistically, TRIM21 catalyzes the K48-linked ubiquitination of TRPV2 at Lys295. TRPV2K295R is resistant to viral-infection-induced TRIM21-dependent ubiquitination and degradation, promoting viral infection more profoundly than wild-type TRPV2 when reconstituted into Lyz2-Cre;Trpv2fl/fl myeloid cells. These findings characterize targeting the TRIM21-TRPV2 axis as a conducive strategy to control viral spread to bystander cells.


Subject(s)
Ribonucleoproteins , TRPV Cation Channels , Ubiquitination , Virus Diseases , Animals , Humans , Mice , Down-Regulation , HEK293 Cells , Herpesvirus 1, Human/physiology , Interferons/metabolism , Mice, Inbred C57BL , Mice, Knockout , Myeloid Cells/metabolism , Ribonucleoproteins/metabolism , TRPV Cation Channels/metabolism , TRPV Cation Channels/genetics , Virus Diseases/metabolism
2.
Animals (Basel) ; 14(6)2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38539959

ABSTRACT

The honeybee, Apis cerana cerana (Ac), is an important pollinator and has adapted to the local ecological environment with relevant coloration. The cuticle coloration of the brown (br) mutant is brown instead of black in wild-type individuals. Therefore, this study aimed to identify and characterize the gene responsible for the br mutation. Genome resequencing with allele segregation measurement using Euclidean distance followed by Lowess regression analysis revealed that the color locus linked to the mutation was located on chromosome 11. A 2-base deletion on exon 4 was identified in the g7628 (yellow) gene after genome assembly and sequence cloning. In addition, the cuticle color of the abdomen of worker bees changed from black to brown when a defect was induced in the yellow gene using short interfering RNA (siRNA); however, the survival rate did not decrease significantly. These results indicate that the yellow gene participated in the body pigmentation, and its defect was responsible for the br mutation. This study promotes the understanding of the molecular basis of body coloration in honeybees, enriching the molecular mechanisms underlying insect pigmentation.

3.
Nature ; 628(8008): 630-638, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38538795

ABSTRACT

Lysosomes are degradation and signalling centres crucial for homeostasis, development and ageing1. To meet diverse cellular demands, lysosomes remodel their morphology and function through constant fusion and fission2,3. Little is known about the molecular basis of fission. Here we identify HPO-27, a conserved HEAT repeat protein, as a lysosome scission factor in Caenorhabditis elegans. Loss of HPO-27 impairs lysosome fission and leads to an excessive tubular network that ultimately collapses. HPO-27 and its human homologue MROH1 are recruited to lysosomes by RAB-7 and enriched at scission sites. Super-resolution imaging, negative-staining electron microscopy and in vitro reconstitution assays reveal that HPO-27 and MROH1 self-assemble to mediate the constriction and scission of lysosomal tubules in worms and mammalian cells, respectively, and assemble to sever supported membrane tubes in vitro. Loss of HPO-27 affects lysosomal morphology, integrity and degradation activity, which impairs animal development and longevity. Thus, HPO-27 and MROH1 act as self-assembling scission factors to maintain lysosomal homeostasis and function.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Lysosomes , Animals , Humans , Caenorhabditis elegans/cytology , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/ultrastructure , Caenorhabditis elegans Proteins/chemistry , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans Proteins/ultrastructure , Homeostasis , Longevity , Lysosomes/metabolism , Lysosomes/ultrastructure , Amino Acid Motifs , Microscopy, Electron
4.
Heliyon ; 9(4): e15231, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37089282

ABSTRACT

Given the complexity and the difficulty of controlling contributors effectively, road passenger transport often results in serious injuries and fatalities. The purpose of this study is to identify the main contributors to coach and bus accidents and to provide policy recommendations for making improvements in accident prevention. The Driving Reliability and Error Analysis Method 3.0 (DREAM 3.0) was modified and used to analyze the contributing factors (i.e. phenotypes and genotypes in DREAM) and their casual mechanisms. By having statistical analysis and social network analysis (SNA) adopted, the main genotypes and phenotypes of the DREAM charts were identified. The results of the study showed that A2.1 (too high speed) was the key phenotype and the main genotypic process chain leading to the phenotype was "inadequate safety management â†’ inadequate training â†’ inadequate skills/knowledge â†’ misjudgment of the situation â†’ too high speed" on all types of road. For A2.1 (too high speed), C2 (misjudgment of the situation) was the dominant genotype, while N5 (inadequate safety management) was the root cause of most genotypes. This suggests that road passenger transport companies, as the responsible parties, often fail to implement or violate safety prevention and control systems. Government regulators should promote the policy system and incentivize them to fulfil their safety management responsibilities. The government should also educate the public and improve the road environment to reduce passenger-related risks and the impact of environmental factors on drivers.

5.
Front Aging Neurosci ; 14: 866272, 2022.
Article in English | MEDLINE | ID: mdl-35645770

ABSTRACT

Background: Reduced elementary somatosensation is common after stroke. However, the measurement of elementary sensation is frequently overlooked in traditional clinical assessments, and has not been evaluated objectively at the cortical level. This study designed a new configuration for the measurement of post-stroke elementary thermal sensation by non-painful cold stimulation (NPCS). The post-stroke cortical responses were then investigated during elementary NPCS on sensory deficiency via electroencephalography (EEG) when compared with unimpaired persons. Method: Twelve individuals with chronic stroke and fifteen unimpaired controls were recruited. A 64-channel EEG system was used to investigate the post-stroke cortical responses objectively during the NPCS. A subjective questionnaire of cold sensory intensity was also administered via a numeric visual analog scale (VAS). Three water samples with different temperatures (i.e., 25, 10, and 0°C) were applied to the skin surface of the ventral forearm for 3 s via glass beaker, with a randomized sequence on either the left or right forearm of a participant. EEG relative spectral power (RSP) and topography were used to evaluate the neural responses toward NPCS with respect to the independent factors of stimulation side and temperature. Results: For unimpaired controls, NPCS initiated significant RSP variations, mainly located in the theta band with the highest discriminative resolution on the different temperatures (P < 0.001). For stroke participants, the distribution of significant RSP spread across all EEG frequency bands and the temperature discrimination was lower than that observed in unimpaired participants (P < 0.05). EEG topography showed that the NPCS could activate extensive and bilateral sensory cortical areas after stroke. Significant group differences on RSP intensities were obtained in each EEG band (P < 0.05). Meanwhile, significant asymmetry cortical responses in RSP toward different upper limbs were observed during the NPCS in both unimpaired controls and participants with stroke (P < 0.05). No difference was found between the groups in the VAS ratings of the different temperatures (P > 0.05). Conclusion: The post-stroke cortical responses during NPCS on sensory deficiency were characterized by the wide distribution of representative RSP bands, lowered resolution toward different temperatures, and extensive activated sensory cortical areas.

6.
ACS Synth Biol ; 11(1): 441-447, 2022 01 21.
Article in English | MEDLINE | ID: mdl-34985865

ABSTRACT

Tyrosol is an aromatic compound with great value that is widely used in the food and pharmaceutical industry. In this study, we reported a synthetic pathway for converting p-coumaric acid (p-CA) into tyrosol in Escherichia coli. We found that the enzyme cascade comprising ferulic acid decarboxylase (FDC1) from Saccharomyces cerevisiae, styrene monooxygenase (SMO), styrene oxide isomerase (SOI) from Pseudomonas putida, and phenylacetaldehyde reductase (PAR) from Solanum lycopersicum could efficiently synthesize tyrosol from p-CA with a conversion rate over 90%. To further expand the range of substrates, we also introduced tyrosine ammonia-lyase (TAL) from Flavobacterium johnsoniae to connect the synthetic pathway with the endogenous l-tyrosine metabolism. We found that tyrosol could be efficiently produced from glycerol, reaching 545.51 mg/L tyrosol in a tyrosine-overproducing strain under shake flasks. In summary, we have established alternative routes for tyrosol synthesis from p-CA (a potential lignin-derived biomass), glucose, and glycerol.


Subject(s)
Escherichia coli , Phenylethyl Alcohol , Escherichia coli/genetics , Escherichia coli/metabolism , Metabolic Engineering , Phenylethyl Alcohol/analogs & derivatives , Phenylethyl Alcohol/metabolism , Tyrosine/metabolism
7.
Soft Robot ; 9(1): 14-35, 2022 02.
Article in English | MEDLINE | ID: mdl-33271057

ABSTRACT

This article presents a novel electromyography (EMG)-driven exoneuromusculoskeleton that integrates the neuromuscular electrical stimulation (NMES), soft pneumatic muscle, and exoskeleton techniques, for self-help upper limb training after stroke. The developed system can assist the elbow, wrist, and fingers to perform sequential arm reaching and withdrawing tasks under voluntary effort control through EMG, with a lightweight, compact, and low-power requirement design. The pressure/torque transmission properties of the designed musculoskeletons were quantified, and the assistive capability of the developed system was evaluated on patients with chronic stroke (n = 10). The designed musculoskeletons exerted sufficient mechanical torque to support joint extension for stroke survivors. Compared with the limb performance when no assistance was provided, the limb performance (measured as the range of motion in joint extension) significantly improved when mechanical torque and NMES were provided (p < 0.05). A pilot trial was conducted on patients with chronic stroke (n = 15) to investigate the feasibility of using the developed system in self-help training and the rehabilitation effects of the system. All the participants completed the self-help device-assisted training with minimal professional assistance. After a 20-session training, significant improvements were noted in the voluntary motor function and release of muscle spasticity at the elbow, wrist, and fingers, as indicated by the clinical scores (p < 0.05). The EMG parameters (p < 0.05) indicated that the muscular coordination of the entire upper limb improved significantly after training. The results suggested that the developed system can effectively support self-help upper limb rehabilitation after stroke. ClinicalTrials.gov Register Number NCT03752775.


Subject(s)
Robotics , Stroke Rehabilitation , Stroke , Humans , Stroke Rehabilitation/methods , Upper Extremity , Wrist Joint
8.
J Neuroeng Rehabil ; 18(1): 34, 2021 02 15.
Article in English | MEDLINE | ID: mdl-33588877

ABSTRACT

BACKGROUND: Fine tactile sensation plays an important role in motor relearning after stroke. However, little is known about its dynamics in post-stroke recovery, principally due to a lack of effective evaluation on neural responses to fine tactile stimulation. This study investigated the post-stroke alteration of cortical connectivity and its functional structure in response to fine tactile stimulation via textile fabrics by electroencephalogram (EEG)-derived functional connectivity and graph theory analyses. METHOD: Whole brain EEG was recorded from 64 scalp channels in 8 participants with chronic stroke and 8 unimpaired controls before and during the skin of the unilateral forearm contacted with a piece of cotton fabric. Functional connectivity (FC) was then estimated using EEG coherence. The fabric stimulation induced FC (SFC) was analyzed by a cluster-based permutation test for the FC in baseline and fabric stimulation. The functional structure of connectivity alteration in the brain was also investigated by assessing the multiscale topological properties of functional brain networks according to the graph theory. RESULTS: In the SFC distribution, an altered hemispheric lateralization (HL) (HL degree, 14%) was observed when stimulating the affected forearm in the stroke group, compared to stimulation of the unaffected forearm of the stroke group (HL degree, 53%) and those of the control group (HL degrees, 92% for the left and 69% for the dominant right limb). The involvement of additional brain regions, i.e., the distributed attention networks, was also observed when stimulating either limb of the stroke group compared with those of the control. Significantly increased (P < 0.05) global and local efficiencies were found when stimulating the affected forearm compared to the unaffected forearm. A significantly increased (P < 0.05) degree of inter-hemisphere FC (interdegree) mainly within ipsilesional somatosensory region and a significantly diminished degree of intra-hemisphere FC (intradegree) (P < 0.05) in ipsilesional primary somatosensory region were observed when stimulating the affected forearm, compared with the unaffected forearm. CONCLUSIONS: The alteration of cortical connectivity in fine tactile sensation post-stroke was characterized by the compensation from the contralesional hemisphere and distributed attention networks related to involuntary attention. The interhemispheric connectivity could implement the compensation from the contralateral hemisphere to the ipsilesional somatosensory region. Stroke participants also exerted increased cortical activities in fine tactile sensation.


Subject(s)
Neural Pathways/physiopathology , Stroke/physiopathology , Touch Perception/physiology , Touch/physiology , Adult , Aged , Brain/physiopathology , Brain Mapping/methods , Electroencephalography/methods , Female , Humans , Male , Middle Aged
9.
PLoS One ; 15(10): e0241378, 2020.
Article in English | MEDLINE | ID: mdl-33112925

ABSTRACT

The precise evaluation of sensory perceptions during fabric-skin interactions is still poorly understood in neuroscience. This study aims to investigate the cortical sensory response to fabric stimuli with different textiles by Electroencephalographic (EEG) spectral intensities, and evaluate the relationships between EEG frequency bands, traditional subjective questionnaires, and the materials' physical properties. Twelve healthy adult participants were recruited to test three fabrics with different textile compositions of 1) cotton, 2) nylon, and 3) polyester and wool. The physical properties of the fabrics were quantitatively evaluated by a Fabric Touch Tester (FTT). Subjects were invited to rate the sensory perception of the fabric samples via a subjective questionnaire and objective EEG recording. Significant differences in the EEG relative spectral power of Theta and Gamma bands were acquired in response to the different fabric stimuli (P<0.05). The Theta and Gamma powers demonstrated a significant correlation with the most of the subjective sensations evaluated by questionnaire and the fabrics' physical properties by FTT (P<0.05). The EEG spectral analysis could feasibly be used for the discrimination of fabric stimuli with different textile compositions and further indicates sensory perceptions during fabric stimulation. This finding may provide evidence for further exploratory research of sensory perceptions via EEG spectral analysis, which could be applied to the study of brain generators of skin tactility in future prostheses and the automatic detection of sensory perception in industries.


Subject(s)
Brain/physiology , Discrimination, Psychological/physiology , Electroencephalography , Textiles , Touch Perception , Female , Humans , Male , Mechanical Phenomena , Surveys and Questionnaires , Young Adult
10.
Oncol Lett ; 20(5): 171, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32934738

ABSTRACT

Triple-negative breast cancer (TNBC) has the poorest prognosis among all types of breast cancer and there is yet no effective therapy. Chemotherapy is the traditional standard of care for patients with TNBC; however, treatment of TNBC with chemotherapy may lead to the enrichment of cancer stem cells (CSCs), which exhibitan enhanced capacity for self-renewal, tumor initiation and metastasis. The present study demonstrated that bufalin, a small molecular compound used in traditional Chinese medicine, exerted anticancer effects on a wide range of cancer cell lines, inhibited cell proliferation through inducing G2/M cell cycle arrest, and triggered apoptosis in the TNBC cell lines MDA-MB-231 and HCC-1937. Consistently, bufalin markedly suppressed TNBC growth in a cell line-derived xenograft model. More importantly, unlike common chemotherapeutic drugs, bufalin reduced the stemness of TNBC stem cells. A mechanistic study suggested that bufalin may suppress the proliferation of TNBC stem cells by inhibiting the expression of octamer-binding transcription factor 4 (OCT4) and sex determining region Y-box 2 (SOX2) in MDA-MB-231 and HCC-1937 cells. These results indicated that bufalin may hold promise as a therapeutic agent in TNBC, and its effects may be mediated through the SOX2/OCT4 axis.

11.
Exp Cell Res ; 395(2): 112191, 2020 10 15.
Article in English | MEDLINE | ID: mdl-32738346

ABSTRACT

Triple-negative breast cancer (TNBC) has the characteristics of fast growth, easy invasion, metastasis, poor prognosis, low tumor-free survival rate and overall survival rate. In this study, the RNA-binding protein MEX3A was selected by using the methods of TCGA database analysis, mRNA microarrays, and tissue chip immunohistochemistry experiments. The high expression of MEX3A is associated with malignancy and poor prognosis of TNBC. In addition, MEX3A knockdown can inhibit the growth and migration of TNBC cells while MEX3A overexpression shows the opposite effect. In vivo experiments, we also demonstrated that downregulating MEX3A can inhibit the tumorigenicity of TNBC cells. The mRNA microarrays and Ingenuity pathway analysis (IPA) were used to explore the downstream of MEX3A, and verified the relationship between PI3K/AKT signaling pathway and MEX3A. Additionally, we have simultaneously up-regulated MEX3A and treated with pathway inhibitors in vitro experiments and found that it can slow down the growth of TNBC cells. In short, we identified MEX3A as a tumor promoter, potential prognostic indicator and therapeutic target for TNBC, may function through the regulation of the PI3K/AKT signaling pathway.


Subject(s)
Cell Movement/physiology , Cell Proliferation/physiology , Phosphoproteins/metabolism , RNA-Binding Proteins/metabolism , Triple Negative Breast Neoplasms/metabolism , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/genetics , Humans , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/physiology
12.
J Neural Eng ; 17(4): 045007, 2020 07 24.
Article in English | MEDLINE | ID: mdl-32613946

ABSTRACT

Objective: Sensory deficiency of fine touch limits the restoration of motor functions after stroke, and its evaluation was seldom investigated from a neurological perspective. In this study, we investigated the cortical response measured by electroencephalography (EEG) on the fine touch sensory impairment during textile fabric stimulation after stroke. Approach: Both participants with chronic stroke (n = 12, stroke group) and those unimpaired (n = 15, control group) were recruited. To investigate fine touch during textile fabric stimulations, full brain EEG recordings (64-channel) were used, as well as the touch sensation questionnaires based on the American Association of Textile Chemists and Colorists (AATCC) Evaluation Procedure 5. During the EEG measurement, relative spectral power (RSP) and EEG topography were used to evaluate the neural responses toward the fabric stimuli. In the subjective questionnaire, the fine touch for fabric stimuli was rated and represented by 13 different sensation parameters. The correlation between the fine touch evaluated by the EEG and the questionnaire was also investigated. Main results: The neural responses of individuals with fine touch impairments after stroke were characterized by a shifted power spectrum to a higher frequency band, enlarged sensory cortical areas and higher RSP intensity (P < 0.05). Asymmetric neural responses were obtained when stimulating different upper limbs for both unimpaired participants and stroke participants (P < 0.05). The fine touch sensation of the stroke participants was impaired even in the unaffected limb. However, as a result of different neural processes, the correlation between the EEG and the questionnaire was weak (r < 0.2). Significance: EEG RSP was able to capture the varied cortical responses induced by textile fabric fine touch stimulations related to the fine touch sensory impairment after stroke.


Subject(s)
Stroke , Touch Perception , Electroencephalography , Humans , Stroke/complications , Stroke/diagnosis , Textiles , Touch
13.
Sensors (Basel) ; 20(9)2020 May 02.
Article in English | MEDLINE | ID: mdl-32370109

ABSTRACT

The piezoelectric actuator is indispensable for driving the micro-manipulator. In this paper, a simplified interval type-2 (IT2) fuzzy system is proposed for hysteresis modelling and feedforward control of a piezoelectric actuator. The partial derivative of the output of IT2 fuzzy system with respect to the modelling parameters can be analytically computed with the antecedent part of IT2 fuzzy rule specifically designed. In the experiments, gradient based optimization was used to identify the IT2 fuzzy hysteresis model. Results showed that the maximum error of model identification is 0.42% with only 3 developed IT2 fuzzy rules. Moreover, the model validation was conducted to demonstrate the generalization performance of the identified model. Based on the analytic inverse of the developed model, feedforward control experiment for tracking sinusoidal trajectory of 20 Hz was carried out. As a result, the hysteresis effect of the piezoelectric actuator was reduced with the maximum tracking error being 4.6%. Experimental results indicated an improved performance of the proposed IT2 fuzzy system for hysteresis modelling and feedforward control of the piezoelectric actuator.

14.
Opt Express ; 28(5): 6859-6867, 2020 Mar 02.
Article in English | MEDLINE | ID: mdl-32225924

ABSTRACT

Based on the rotational Doppler effect, an orbital angular momentum beam can measure the lateral rotation velocity of an object, which has broad application prospects. However, all existing research focus on the light spot center coinciding with the rotation center, or only with small center offset. This is difficult to ensure in remote detection applications. In this paper, the rotational Doppler frequency shifts under three cases, including no center offset, small center offset and large center offset, are analyzed theoretically. Through theoretical research results, a novel method of measuring rotation velocity is proposed, with the light spot completely deviated out of the rotation center. A laboratory verification experiment shows that this proposed method breaks the limit of center offset of lateral rotation velocity measurement and is of great significance to the remote detection of non-cooperative rotation object.

15.
Opt Express ; 28(3): 4320-4332, 2020 Feb 03.
Article in English | MEDLINE | ID: mdl-32122086

ABSTRACT

Super-resolved angular displacement estimation is of crucial significance to the field of quantum information processing. Here we report an estimation protocol based on a Sagnac interferometer fed by a coherent state carrying orbital angular momentum. In a lossless scenario, through the use of parity measurement, our protocol can achieve a 4ℓ-fold super-resolved output with quantum number ℓ; meanwhile, a shot-noise-limited sensitivity saturating the quantum Cramér-Rao bound is reachable. We also consider the effects of several realistic factors, including nonideal state preparation, photon loss, and inefficient measurement. Finally, with mean photon number N¯=2.297 and ℓ = 1 taken, we experimentally demonstrate a super-resolved effect of angular displacement with a factor of 7.88.

16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(2): 545-548, 2019 Apr.
Article in Chinese | MEDLINE | ID: mdl-30998168

ABSTRACT

OBJECTIVE: To investigate the gene mutation types and distribution features of α- and ß-thalassemia in reproductive population of Xing bin district of Guangxi Lai bin city so as to provide the scientific basis for formulating the preventive and control measures. METHODS: The high risk population with thalassemia in 6 498 people of child-bearing age admited in department of antenatal care of our hospital from January 2017 to December 2017 were screened by blood cell test and hemoglobin electrophoresis. The gene mutation types and mutation frequency in αandßthalassemia positive cases were diagnosed and analyzied by Gap-PCR and PCR-RDB. RESULTS: The inital screening showed that there were 1 432 cases of thalassemia positive accounting for 22.04%; the gene diagnoses showed that there were 920 cases of thalassemia gene positive accounting for 14.16%. Among 920 cases, 593 cases were α-thalassemia accounting for 64.45% (593/920); the gene mutation types were 19 kinds. The α-deletion type gene was mainly --SEA (47.22%), the α-mutatin type gene was mainly -αcsα(13.66%); 260 cases were the ß-thalassemia accounting for 28.26%, (260/920), the gene mutation types were 9 kinds, out of which the ß41-42 ßN was main (50.38%), followed by ß17/ßN (38.08%),there were 2 kinds of gene mutation types accounted for 88.46%; the αß-thalassemia numbered 67 cases (7.28%), the mutation types were mainly --SEA/ß41-42 (17.91%) and -α3.7/ß41-42 (17.91%). CONCLUSION: The α-and ß-thalassemia mostly observed in the childbearing population of Laibin city Xinbin district possess the gene comblexity and diversity as well as the significant genetic heterogeneily.The results of this study provide the reference basis for the prevention of thalassemia and eugenic works.


Subject(s)
Mutation , Child , China , Female , Genotype , Humans , Pregnancy , alpha-Thalassemia , beta-Thalassemia
17.
PLoS Biol ; 17(4): e3000211, 2019 04.
Article in English | MEDLINE | ID: mdl-30990821

ABSTRACT

During spermatogenesis, interconnected haploid spermatids segregate undesired cellular contents into residual bodies (RBs) before detaching from RBs. It is unclear how this differentiation process is controlled to produce individual spermatids or motile spermatozoa. Here, we developed a live imaging system to visualize and investigate this process in C. elegans. We found that non-muscle myosin 2 (NMY-2)/myosin II drives incomplete cytokinesis to generate connected haploid spermatids, which are then polarized to segregate undesired cellular contents into RBs under the control of myosin II and myosin VI. NMY-2/myosin II extends from the pseudo-cleavage furrow formed between two haploid spermatids to the spermatid poles, thus promoting RB expansion. In the meantime, defective spermatogenesis 15 (SPE-15)/myosin VI migrates from spermatids towards the expanding RB to promote spermatid budding. Loss of myosin II or myosin VI causes distinct cytoplasm segregation defects, while loss of both myosins completely blocks RB formation. We found that the final separation of spermatids from RBs is achieved through myosin VI-mediated cytokinesis, while myosin II is dispensable at this step. SPE-15/myosin VI and F-actin form a detergent-resistant actomyosin VI ring that undergoes continuous contraction to promote membrane constriction between spermatid and RB. We further identified that RGS-GAIP-interacting protein C terminus (GIPC)-1 and GIPC-2 cooperate with myosin VI to regulate contractile ring formation and spermatid release. Our study reveals distinct roles of myosin II and myosin VI in spermatid differentiation and uncovers a novel myosin VI-mediated cytokinesis process that controls spermatid release.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , Myosins/metabolism , Spermatids/metabolism , Actins/metabolism , Animals , Caenorhabditis elegans , Cell Differentiation/physiology , Cytoplasm/metabolism , Male , Myosin Heavy Chains/metabolism , Nonmuscle Myosin Type IIA/metabolism , Spermatogenesis/physiology , Spermatozoa/metabolism
18.
Opt Express ; 27(4): 5512-5522, 2019 Feb 18.
Article in English | MEDLINE | ID: mdl-30876153

ABSTRACT

We demonstrate a tried-and-true binary strategy for angular displacement estimation, of which the measuring system is a modified Mach-Zehnder interferometer fed by a coherent state carrying orbital angular momentum, and two Dove prisms are embedded in two arms. Unlike previous protocols, in this paper, we use fidelity instead of standard deviation to evaluate the detection strategies. Two binary strategy candidates, parity detection and Z detection, are considered and compared. In addition, we study the effects of several realistic scenarios on the estimation protocol, including transmission loss, detection efficiency, dark counts, and those which are a combination thereof. Finally, we exhibit a proof-of-principle experiment, the results suggest a resolution enhancement effect with a factor of 3.72.

19.
Immunotargets Ther ; 7: 77-81, 2018.
Article in English | MEDLINE | ID: mdl-30538965

ABSTRACT

BACKGROUND: T cell immunodeficiency is a common feature in patients with different kinds of hematological disease such as T cell non-Hodgkin lymphoma (T-NHL), B cells NHL (B-NHL), NK/T cell NHL (NK/T-CL) and acute myeloid leukemia (AML). In our recent research, we found that significantly lower expression levels in MALT1 and NF-κB were related to suppression of T cell activation. Therefore, this study was conducted to further investigate the role of downregulating MALT1 in the development of immunodeficiency in T cells. METHODS: We induced activation inhibition in CD3+ T cells by MALT1 knockdown. Then we characterized the gene expression profile after MALT1 suppression by microarray analysis. RESULT: The differentially expressed genes were ZAP-70, p65, MDM2, ATM, NFATC2 which participate in the NF-κB, p53, and NFAT pathways in CD3+ T cells after MALT1 downregulation. CONCLUSION: MALT1 suppression may contribute to immunodeficiency in T cells via suppression of T cell activation and proliferation pathways. These data may help to explain some of the characteristics of immunodeficiency of T cells.

20.
Opt Express ; 26(25): 33080-33090, 2018 Dec 10.
Article in English | MEDLINE | ID: mdl-30645465

ABSTRACT

In this paper, we propose a protocol for the estimation of angular displacement based upon orbital angular momentum and an SU(1,1)-SU(2) hybrid interferometer. This interferometer consists of an optical parametric amplifier, a beam splitter, and reflection mirrors; the balanced homodyne detection is used as the detection strategy. The results indicate that super-resolution and super-sensitivity can be achieved with an ideal scenario. Additionally, we study the effect of photon loss on resolution and sensitivity, and the robustness of our protocol is also discussed. Finally, the advantage of our protocol compared with an SU(1,1) protocol is demonstrated, and the merits of orbital angular momentum-enhanced protocol are summarized.

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