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1.
Acta Pharmacol Sin ; 41(1): 34-46, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31515530

RESUMO

Abnormal growth of the intimal layer of blood vessels (neointima formation) contributes to the progression of atherosclerosis and in-stent restenosis. Recent evidence shows that the 18-kDa translocator protein (TSPO), a mitochondrial membrane protein, is involved in diverse cardiovascular diseases. In this study we investigated the role of endogenous TSPO in neointima formation after angioplasty in vitro and in vivo. We established a vascular injury model in vitro by using platelet-derived growth factor-BB (PDGF-BB) to stimulate rat thoracic aortic smooth muscle cells (A10 cells). We found that treatment with PDGF-BB (1-20 ng/mL) dose-dependently increased TSPO expression in A10 cells, which was blocked in the presence of PKC inhibitor or MAPK inhibitor. Overexpression of TSPO significantly promoted the proliferation and migration in A10 cells, whereas downregulation of TSPO expression by siRNA or treatment with TSPO ligands PK11195 or Ro5-4864 (104 nM) produced the opposite effects. Furthermore, we found that PK11195 (10-104 nM) dose-dependently activated AMPK in A10 cells. PK11195-induced inhibition on the proliferation and migration of PDGF-BB-treated A10 cells were abolished by compound C (an AMPK-specific inhibitor, 103 nM). In rats with balloon-injured carotid arteries, TSPO expression was markedly upregulated in the carotid arteries. Administration of PK11195 (3 mg/kg every 3 days, ip), starting from the initial balloon injury and lasting for 2 weeks, greatly attenuated carotid neointima formation by suppressing balloon injury-induced phenotype switching of VSMCs (increased α-SMA expression). These results suggest that TSPO is a vascular injury-response molecule that promotes VSMC proliferation and migration and is responsible for the neointima formation after vascular injury, which provides a novel therapeutic target for various cardiovascular diseases including atherosclerosis and restenosis.

2.
ACS Appl Mater Interfaces ; 11(50): 46938-46946, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31756082

RESUMO

Solar vapor generation by localized heating and evaporation has potential to be a viable and "green" way to produce fresh water. This work reports a carbon black-coated cotton fabric with a tunable water delivery property for high-efficiency solar vapor generation under 1 sun. The fabric is prepared by an electrospray of poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) on one-side of the fabric followed by dip-coating of the fabric with carbon black as a photothermal absorber. Depending on the duration of electrospray, the roughness gradient generated by the PVDF-HFP layer in the fabric leads to guided and continuous one-way water transport from the electrosprayed hydrophobic side to the hydrophilic side with a tunable delivery rate. The tunable water delivery capability of the fabric regulates the amount of water supplied to the vicinity of the photothermal absorber. Additionally, the fabric shows excellent broadband absorption and low thermal conductivity. In comparison with the carbon black-coated fabric without a roughness gradient, the regulation of water improves the solar vapor conversion efficiency, owing to reduced heat loss and better heat allocation. Under optimal conditions, a solar vapor conversion efficiency of 88.9% and a stable water evaporation rate of 1.33 kg (m2·h)-1 under 1 sun are achieved.

3.
Inorg Chem ; 58(21): 14876-14884, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31637917

RESUMO

A series of functional cation-regulated isopolymolybdate-based organic-inorganic hybrid compounds, Na2H2[Mo4O12(C8H17O5N)2]·10H2O (1), Na2[M(Bis-tris)(H2O)]2[Mo7O24]·10H2O [M = Cu, 2; Ni, 3; Co, 4; Zn, 5; Bis-tris = 2,2-Bis(hydroxymethyl)-2,2',2″-nitrilotriethanol], and (NH4)2[M(Bis-tris)(H2O)]2[Mo7O24]·6H2O (M = Zn, 6; Cu, 7), were synthesized and characterized toward advanced molecular catalyst design. Compound 1 is a covalently bonded adduct, and its self-assembly process can be probed by electrospray ionization mass spectrometry (ESI-MS). Compounds 2-7 are polyoxometalate (POM)-based hybrids containing classic heptamolybdate anions and complex cations with Bis-tris ligands. All of these compounds showed remarkable catalytic effects for selective sulfide oxidation. To the best of our knowledge, compound 5 presents the best catalytic activity so far among the reported hybrid materials with common easily synthesized small-molecule POM clusters and also exhibits outstanding reliability. The conclusion of the catalytic effect is drawn from the results that Zn-based compounds have better catalytic effects than other transition-metal-containing compounds and the compound constructed by Na+ has higher catalytic activity than that constructed by NH4+. The mechanism studies show that the improvements of the catalytic performance are caused by the synergy between classic heptamolybdate anions and complex cations. ESI-MS data and UV-vis spectra revealed that the POM anions can form intermediate peroxomolybdenum units during catalytic reaction. Further, the combination of the substrate thioanisole with complex cations was characterized by NMR experiments and UV-vis spectra. Thus, a new synergistic mechanism of anions and cations is proposed in which the activated thioanisole is used as a nucleophile to attack the peroxomolybdenum bonds, and this provides a new strategy in the design of reliable POM-based catalysts.

4.
J Phys Chem Lett ; 10(21): 6656-6663, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31608641

RESUMO

Two-dimensional (2D) Dirac cone materials exhibit linear energy dispersion at the Fermi level, where the effective masses of carriers are very close to zero and the Fermi velocity is ultrahigh, only 2-3 orders of magnitude lower than the light velocity. Such Dirac cone materials have great promise in high-performance electronic devices. Herein, we have employed the genetic algorithm methods combined with first-principles calculations to propose a new 2D anisotropic Dirac cone material, an orthorhombic boron phosphide (BP) monolayer named borophosphene. Molecular dynamics simulation and phonon dispersion have been used to evaluate the dynamic and thermal stability of borophosphene. Because of the unique arrangements of B-B and P-P dimers, the mechanical and electronic properties are highly anisotropic. Of great interest is the fact that the Dirac cone of the borophosphene is robust, independent of in-plane biaxial and uniaxial strains, and can also be observed in its one-dimensional zigzag nanoribbons and armchair nanotubes. The Fermi velocities are ∼105 m/s, on the same order of magnitude as that of graphene. By using a tight-binding model, the origin of the Dirac cone of borophosphene is analyzed. Moreover, a unique feature of self-doping can be induced by the in-plane biaxial and uniaxial strains of borophosphene and the curvature effect of nanotubes, which is greatly beneficial for realizing high-speed carriers (holes). Our results suggest that the borophosphene holds great promise for high-performance electronic devices, which could promote experimental and theoretical studies for further exploring the potential applications of other 2D Dirac cone sheets.

5.
Proc Natl Acad Sci U S A ; 116(41): 20274-20279, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31548414

RESUMO

The condensation of half-light half-matter exciton polaritons in semiconductor optical cavities is a striking example of macroscopic quantum coherence in a solid-state platform. Quantum coherence is possible only when there are strong interactions between the exciton polaritons provided by their excitonic constituents. Rydberg excitons with high principal value exhibit strong dipole-dipole interactions in cold atoms. However, polaritons with the excitonic constituent that is an excited state, namely Rydberg exciton polaritons (REPs), have not yet been experimentally observed. Here, we observe the formation of REPs in a single crystal CsPbBr3 perovskite cavity without any external fields. These polaritons exhibit strong nonlinear behavior that leads to a coherent polariton condensate with a prominent blue shift. Furthermore, the REPs in CsPbBr3 are highly anisotropic and have a large extinction ratio, arising from the perovskite's orthorhombic crystal structure. Our observation not only sheds light on the importance of many-body physics in coherent polariton systems involving higher-order excited states, but also paves the way for exploring these coherent interactions for solid-state quantum optical information processing.

6.
J Biol Chem ; 294(47): 17725-17734, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31562247

RESUMO

Mitochondria undergo morphological and dynamic changes in response to environmental stresses. Few studies have focused on addressing mitochondrial remodeling under stress. Using the fission yeast Schizosaccharomyces pombe as a model organism, here we investigated mitochondrial remodeling under glucose starvation. We employed live-cell microscopy to monitor mitochondrial morphology and dynamics of cells in profusion chambers under glucose starvation. Our results revealed that mitochondria fragment within minutes after glucose starvation and that the dynamin GTPase Dnm1 is required for promoting mitochondrial fragmentation. Moreover, we found that glucose starvation enhances Dnm1 localization to mitochondria and increases the frequency of mitochondrial fission but decreases PKA activity. We further demonstrate that low PKA activity enhances glucose starvation-induced mitochondrial fragmentation, whereas high PKA activity confers resistance to glucose starvation-induced mitochondrial fragmentation. Moreover, we observed that AMP-activated protein kinase is not involved in regulating mitochondrial fragmentation under glucose starvation. Of note, glucose starvation-induced mitochondrial fragmentation was associated with enhanced reactive oxygen species production. Our work provides detailed mechanistic insights into mitochondrial remodeling in response to glucose starvation.

7.
J Phys Chem Lett ; 10(20): 6174-6183, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31538792

RESUMO

Plasmon photochemistry can potentially play a significant role in photocatalysis. To realize this potential, it is critical to enhance the plasmon excited hot carrier transfer and collection. However, the lack of atomistic understanding of the carrier transfer across the interface, especially when the carrier is still "hot", makes it challenging to design a more efficient system. In this work, we apply the nonadiabatic molecular dynamics simulation to study hot carrier dynamics in the system of a Au nanocluster on top of a GaN surface. By setting up the initial excited hole in Au, the carrier transfer from Au to GaN is found to be on a subpicosecond time scale. The hot hole first cools to the band edge of Au d-states while it transfers to GaN. After the hole has cooled down to the band edge of GaN, we find that some of the charges can return back to Au. By applying different external potentials to mimic the Schottky barrier band bending, the returning charge can be reduced, demonstrating the importance of the internal electric field. Finally, with the understanding of the carrier transfer's pathway, we suggest that a ZnO layer between GaN and Au can effectively block the "cold" carrier from returning back to Au but still allow the hot carrier to transfer from Au to GaN.

8.
Mol Ther Nucleic Acids ; 18: 34-44, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31479923

RESUMO

Insulin resistance (IR) is the primary pathological mechanism underlying type 2 diabetes mellitus (T2DM). Here, the study aimed to ascertain whether and how exercise mediates IR in T2DM. An in vivo mouse model of high-fat diet-induced IR and an in vitro high-glucose-induced IR model were constructed. High long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) expression was detected in T2MD and was positively correlated with HOMA-IR and resistin levels. Then, short hairpin RNA targeting MALAT1 (sh-MALAT1) or pcDNA-MALAT1 was delivered into human umbilical vein endothelial cells (HUVECs) to knock down or upregulate its expression, respectively. Silencing of MALAT1 resulted in reduced levels of resistin, Ang II, tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), endothelin-1 (ET-1), and p-insulin receptor substrate-1 (p-IRS)/ISR-1, and decreased cell migration, as well as enhanced glucose uptake and levels of nitric oxide (NO) and p-Akt/Akt. In the IR mouse model, exercise was observed to downregulate MALAT1 to reduce resistin, whereby exercise reduced homeostatic model assessment-insulin resistance (HOMA-IR). Besides, exercise also elevated microRNA-382-3p (miR-382-3p) expression in the serum of IR mice. Dual-luciferase reporter and RNA binding protein immunoprecipitation (RIP) assays identified that MALAT1 could bind to miR-382-3p to upregulate resistin. Collectively, the key observations of the study provide evidence that inhibition of MALAT1 elevates miR-382-3p to repress resistin, which consequently underlies the mechanism of exercise protecting against IR, highlighting a direction for T2DM therapy development.

9.
RNA Biol ; 16(10): 1513-1520, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31298604

RESUMO

Type III CRISPR-Cas systems code for a multi-subunit ribonucleoprotein (RNP) complex that mediates DNA cleavage and synthesizes cyclic oligoadenylate (cOA) second messenger to confer anti-viral immunity. Both immune activities are to be activated upon binding to target RNA transcripts by their complementarity to crRNA, and autoimmunity avoidance is determined by extended complementarity between the 5'-repeat tag of crRNA and 3'-flanking sequences of target transcripts (anti-tag). However, as to how the strategy could achieve stringent autoimmunity avoidance remained elusive. In this study, we systematically investigated how the complementarity of the crRNA 5'-tag and anti-tag (i.e., tag complementarity) could affect the interference activities (DNA cleavage activity and cOA synthesis activity) of Cmr-α, a type III-B system in Sulfolobus islandicus Rey15A. The results revealed an increasing suppression on both activities by increasing degrees of tag complementarity and a critical function of the 7th nucleotide of crRNA in avoiding autoimmunity. More importantly, mutagenesis of Cmr3α exerts either positive or negative effects on the cOA synthesis activity depending on the degrees of tag complementarity, suggesting that the subunit, coupling with the interaction between crRNA tag and anti-tag, function in facilitating immunity and avoiding autoimmunity in Type III-B systems.

10.
Chem Commun (Camb) ; 55(59): 8639-8642, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31286125

RESUMO

A supermolecular building block approach was utilized to fabricate three isoreticular chiral metal-organic frameworks with different pore environments based on enantiopure tetracarboxylate ligands of biphenol, which were found to be highly effective heterogeneous catalysts for the CO2 fixation reaction.

11.
Arch Virol ; 164(8): 2209-2213, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161389

RESUMO

The complete genome of a double-stranded RNA (dsRNA) mycovirus, Phoma matteuccicola partitivirus 1 (PmPV1) was sequenced. It consists of two dsRNA segments, 1664 bp (dsRNA-1) and 1383 bp (dsRNA-2) in length, each containing a single open reading frame (ORF) potentially encoding a 46.78-kDa protein and a 40.92-kDa protein, respectively. dsRNA-1 encodes a putative polypeptide with a conserved RNA-dependent RNA polymerase (RdRp) domain that shows sequence similarity to the corresponding proteins of partitiviruses. The protein encoded by dsRNA-2 has no significant similarity to the typical coat proteins (CPs) of partitiviruses, but structure analysis nevertheless suggested that it might function as a coat protein. Purified viral particles of PmPV1 were isometric and approximately 29 nm in diameter. Phylogenetic analysis showed that PmPV1 is closely related to members of the genus Gammapartitivirus within the family Partitiviridae but forms a separate branch with Colletotrichum acutatum RNA virus 1 and Ustilaginoidea virens partitivirus 2. This is the first report of the full-length nucleotide sequence of a novel virus of the genus Gammapartitivirus infecting P. matteuccicola strain LG915, the causal agent of leaf blight of Curcuma wenyujin.


Assuntos
Ascomicetos/virologia , Micovírus/genética , Genoma Viral/genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/genética , Curcuma/virologia , Genômica/métodos , Fases de Leitura Aberta/genética , Filogenia , Doenças das Plantas/virologia , RNA Replicase/genética , Vírus de RNA/genética , RNA de Cadeia Dupla/genética , RNA Viral/genética , Análise de Sequência de DNA/métodos
12.
J Mol Cell Biol ; 11(11): 944-955, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31087092

RESUMO

Microtubules grow not only from the centrosome but also from various noncentrosomal microtubule-organizing centers (MTOCs), including the nuclear envelope (NE) and pre-existing microtubules. The evolutionarily conserved proteins Mto1/CDK5RAP2 and Alp14/TOG/XMAP215 have been shown to be involved in promoting microtubule nucleation. However, it has remained elusive as to how the microtubule nucleation promoting factors are specified to various noncentrosomal MTOCs, particularly the NE, and how these proteins coordinate to organize microtubule assembly. Here, we demonstrate that in the fission yeast Schizosaccharomyces pombe, efficient interphase microtubule growth from the NE requires Alp7/TACC, Alp14/TOG/XMAP215, and Mto1/CDK5RAP2. The absence of Alp7, Alp14, or Mto1 compromises microtubule regrowth on the NE in cells undergoing microtubule repolymerization. We further demonstrate that Alp7 and Mto1 interdependently localize to the NE in cells without microtubules and that Alp14 localizes to the NE in an Alp7 and Mto1-dependent manner. Tethering Mto1 to the NE in cells lacking Alp7 partially restores microtubule number and the efficiency of microtubule generation from the NE. Hence, our study delineates that Alp7, Alp14, and Mto1 work in concert to regulate interphase microtubule regrowth on the NE.

13.
J Mol Cell Biol ; 11(11): 956-966, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31071203

RESUMO

Spatial regulation of microtubule catastrophe is important for controlling microtubule length and consequently contributes to the proper establishment of cell polarity and cell growth. The +TIP proteins including Tip1/CLIP-170, Klp5/Kinesin-8, and Alp14/XMAP215 reside at microtubule plus ends to regulate microtubule dynamics. In the fission yeast Schizosaccharomyces pombe, Tip1 and Alp14 serve as microtubule-stabilizing factors, while Klp5 functions oppositely as a catastrophe-promoting factor. Despite that Tip1 has been shown to play a key role in restricting microtubule catastrophe to the cell end, how Tip1 fulfills the role remains to be determined. Employing live-cell microscopy, we showed that the absence of Tip1 impairs the localization of both Klp5 and Alp14 at microtubule plus ends, but the absence of Klp5 prolongs the residence time of Tip1 at microtubule plus ends. We further revealed that Klp5 accumulates behind Tip1 at microtubule plus ends in a Tip1-dependent manner. In addition, artificially tethering Klp5 to microtubule plus ends promotes premature microtubule catastrophe, while tethering Alp14 to microtubule plus ends in the cells lacking Tip1 rescues the phenotype of short microtubules. These findings establish that Tip1 restricts microtubule catastrophe to the cell end likely by spatially restricting the microtubule catastrophe activity of Klp5 and stabilizing Alp14 at microtubule plus ends. Thus, the work demonstrates the orchestration of Tip1, Alp14, and Klp5 in ensuring microtubule catastrophe at the cell end.

14.
Cell Syst ; 8(3): 267-273.e3, 2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30878356

RESUMO

Systems biology requires not only genome-scale data but also methods to integrate these data into interpretable models. Previously, we developed approaches that organize omics data into a structured hierarchy of cellular components and pathways, called a "data-driven ontology." Such hierarchies recapitulate known cellular subsystems and discover new ones. To broadly facilitate this type of modeling, we report the development of a software library called the Data-Driven Ontology Toolkit (DDOT), consisting of a Python package (https://github.com/idekerlab/ddot) to assemble and analyze ontologies and a web application (http://hiview.ucsd.edu) to visualize them. Using DDOT, we programmatically assemble a compendium of ontologies for 652 diseases by integrating gene-disease mappings with a gene similarity network derived from omics data. For example, the ontology for Fanconi anemia describes known and novel disease mechanisms in its hierarchy of 194 genes and 74 subsystems. DDOT provides an easy interface to share ontologies online at the Network Data Exchange.

16.
J Diabetes Res ; 2019: 1073131, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800684

RESUMO

Objective: This study is aimed at assessing the effectiveness of a simple outpatient diabetes self-management education programme. Methods: In the study, 60 patients with type 2 diabetes mellitus were randomly allocated into the control group (n = 30) and intervention group (n = 30). Regular and 2-session health education programmes were provided. The summary of diabetes self-care activity measure, problem areas in the diabetes scale, fasting blood glucose, postprandial 2 h blood glucose, and HbA1c were measured before and after the intervention to assess the effects of this 2-session diabetes education programme. Results: The total mean score of the summary of diabetes self-care activities measure was 17.60 ± 6.63 points. The problem areas in the diabetes scale revealed that the total mean score was 29.82 ± 15.22 points; 27% of the patients had diabetes-related distress, while 9% suffered from severe emotional distress. Compared with the control group, scores of the summary of diabetes self-care activities measure and problem areas in the diabetes scale, fasting blood glucose, postprandial 2 h blood glucose, and HbA1c were significantly improved in the intervention group after the intervention (P < 0.01). Conclusion: This study showed that the 2-session diabetes education programme could effectively improve the level of self-reported self-management, psychological distress, and glycemic control in patients with type 2 diabetes mellitus.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2/sangue , Hemoglobina A Glicada , Educação de Pacientes como Assunto , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Qualidade de Vida , Autogestão , Resultado do Tratamento
17.
Lipids Health Dis ; 18(1): 6, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30611282

RESUMO

OBJECTIVE: To emphasize the mechanism of concurrent exercise effect on lipid disorders in insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: Twenty male ApoE knockout mice were randomly divided into two groups: HFD group (n = 10) fed a high fat diet, and HFDE group (n = 10) with high-fat diet intervention for 12 weeks and swimming exercise. Other ten healthy male C57BL/6 J mice were fed a normal diet, and included as control group. Retro-orbital blood samples were collected for biochemical analysis. Oil red O staining of liver tissues was performed to confirm the exercise effect. Western blotting was performed to evaluate the expressions of PPAR-γ, CPT-1, MCAD. RESULTS: The levels of TG, TC, LDL, FFA, FIN, FPG and Homa-IRI in the HFD group were significantly higher than ND group, while these were markedly decreased in the HFDE group compared with HFD group. The Oil Red O staining of liver samples further confirmed the exercise effect on the change of lipid deposition in the liver. Western blotting showed increased expressions of PPAR-γ, CPT-1, MCAD induced by high fat diet were significantly downregulated by exercise. CONCLUSION: A concurrent 12-week exercise protocol alleviated the lipid metabolism disorders of IR and NAFLD, probably via PPAR-γ/CPT-1/MCAD signaling.


Assuntos
Caderinas/genética , Carnitina O-Palmitoiltransferase/genética , Metabolismo dos Lipídeos/genética , Hepatopatia Gordurosa não Alcoólica/terapia , PPAR gama/genética , Condicionamento Físico Animal , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Caderinas/agonistas , Caderinas/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos não Esterificados/sangue , Regulação da Expressão Gênica , Resistência à Insulina , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR gama/agonistas , PPAR gama/metabolismo , Transdução de Sinais , Natação , Triglicerídeos/sangue
18.
IEEE Trans Cybern ; 49(7): 2652-2663, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29993766

RESUMO

This paper focuses on the motion estimation problem of ground vehicles using odometry and monocular visual sensors. While the keyframe-based batch optimization methods become the mainstream approach in mobile vehicle localization and mapping, the keyframe poses are usually represented by SE(3) in vision-based methods or SE(2) in methods based on range scanners. For a ground vehicle, this paper proposes a new SE(2)-constrained SE(3) parameterization of its poses, which can be easily achieved in the batch optimization framework using specially formulated edges. Utilizing such a parameterization of poses, a complete odometry-vision-based motion estimation system is developed. The system is designed in a commonly used structure of graph optimization, providing high modularity and flexibility for further implementation or adaptation. Its superior performance in terms of accuracy on a ground vehicle platform is validated by real-world experiments in industrial indoor environments.

19.
J Biol Chem ; 294(3): 968-980, 2019 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-30459232

RESUMO

The centromere is an evolutionarily conserved eukaryotic protein machinery essential for precision segregation of the parental genome into two daughter cells during mitosis. Centromere protein A (CENP-A) organizes the functional centromere via a constitutive centromere-associated network composing the CENP-T complex. However, how CENP-T assembles onto the centromere remains elusive. Here we show that CENP-T binds directly to Holliday junction recognition protein (HJURP), an evolutionarily conserved chaperone involved in loading CENP-A. The binding interface of HJURP was mapped to the C terminus of CENP-T. Depletion of HJURP by CRISPR-elicited knockout minimized recruitment of CENP-T to the centromere, indicating the importance of HJURP in CEPN-T loading. Our immunofluorescence analyses indicate that HJURP recruits CENP-T to the centromere in S/G2 phase during the cell division cycle. Significantly, the HJURP binding-deficient mutant CENP-T6L failed to locate to the centromere. Importantly, CENP-T insufficiency resulted in chromosome misalignment, in particular chromosomes 15 and 18. Taken together, these data define a novel molecular mechanism underlying the assembly of CENP-T onto the centromere by a temporally regulated HJURP-CENP-T interaction.


Assuntos
Proteína Centromérica A/metabolismo , Centrômero/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fase G2/fisiologia , Fase S/fisiologia , Centrômero/genética , Proteína Centromérica A/genética , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/genética , Células HEK293 , Células HeLa , Humanos
20.
Mol Biol Cell ; 30(2): 256-267, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30427751

RESUMO

Microtubule biogenesis initiates at various intracellular sites, including the centrosome, the Golgi apparatus, the nuclear envelope, and preexisting microtubules. Similarly, in the fission yeast Schizosaccharomyces pombe, interphase microtubules are nucleated at the spindle pole body (SPB), the nuclear envelope, and preexisting microtubules, depending on Mto1 activity. Despite the essential role of Mto1 in promoting microtubule nucleation, how distribution of Mto1 in different sites is regulated has remained elusive. Here, we show that the J-domain cochaperone Rsp1 interacts with Mto1 and specifies the localization of Mto1 to non-SPB nucleation sites. The absence of Rsp1 abolishes the localization of Mto1 to non-SPB nucleation sites, with concomitant enrichment of Mto1 to the SPB and the nuclear envelope. In contrast, Rsp1 overexpression impairs the localization of Mto1 to all microtubule organization sites. These findings delineate a previously uncharacterized mechanism in which Rsp1-Mto1 interaction orchestrates non-SPB microtubule formation.


Assuntos
Proteínas de Transporte/metabolismo , Centrossomo/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/citologia , Schizosaccharomyces/metabolismo , Modelos Biológicos , Ligação Proteica , Transporte Proteico , Corpos Polares do Fuso/metabolismo
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