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1.
Animals (Basel) ; 14(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38791628

ABSTRACT

Aberrant expression of the heat shock proteins and factors was revealed to be closely associated with male reproduction. Heat shock factor 2 (HSF2) is a transcription factor that is involved in the regulation of diverse developmental pathways. However, the role and the corresponding molecular mechanism of HSF2 in male cattle-yak sterility are still poorly understood. Therefore, the aim of this study was to obtain the sequence and the biological information of the cattle-yak HSF2 gene and to investigate the spatiotemporal expression profiles of the locus during the development of cattle-yak testes. Additionally, the differential expression was analyzed between the cattle-yak and the yak, and the methylation of corresponding promoter regions was compared. Our results showed an additional 54 bp fragment and a missense mutation (lysine to glutamic acid) were presented in the cattle-yak HSF2 gene, which correlated with enriched expression in testicular tissue. In addition, the expression of the HSF2 gene showed dynamic changes during the growth of the testes, reaching a peak in adulthood. The IHC indicated that HSF2 protein was primarily located in spermatocytes (PS), spermatogonia (SP), and Sertoli cells (SC) in cattle-yak testes, compared with the corresponding cells of cattle and the yak. Furthermore, bisulfite-sequencing PCR (BSP) revealed that the methylated CpG sites in the promoter region of the cattle-yak HSF2 were more numerous than in the yak counterpart, which suggests hypermethylation of this region in the cattle-yak. Taken together, the low expression abundance and hypermethylation of HSF2 may underpin the obstruction of spermatogenesis, which leads to male cattle-yak infertility. Our study provided a basic guideline for the HSF2 gene in male reproduction and a new insight into the mechanisms of male cattle-yak sterility.

2.
Int J Mol Sci ; 25(9)2024 May 02.
Article in English | MEDLINE | ID: mdl-38732180

ABSTRACT

The Pacific white shrimp, Penaeus vannamei, is highly susceptible to white spot syndrome virus (WSSV). Our study explored the transcriptomic responses of P. vannamei from resistant and susceptible families, uncovering distinct expression patterns after WSSV infection. The analysis revealed a higher number of differentially expressed genes (DEGs) in the susceptible family following WSSV infection compared to the resistant family, when both were evaluated against their respective control groups, indicating that the host resistance of the family line influences the transcriptome. The results also showed that subsequent to an identical duration following WSSV infection, there were more DEGs in P. vannamei with a high viral load than in those with a low viral load. To identify common transcriptomic responses, we profiled DEGs across families at 96 and 228 h post-infection (hpi). The analysis yielded 64 up-regulated and 37 down-regulated DEGs at 96 hpi, with 33 up-regulated and 34 down-regulated DEGs at 228 hpi, showcasing the dynamics of the transcriptomic response over time. Real-time RT-PCR assays confirmed significant DEG expression changes post-infection. Our results offer new insights into shrimp's molecular defense mechanisms against WSSV.


Subject(s)
Disease Resistance , Gene Expression Profiling , Penaeidae , Transcriptome , White spot syndrome virus 1 , Animals , Penaeidae/virology , Penaeidae/genetics , Penaeidae/immunology , White spot syndrome virus 1/genetics , Gene Expression Profiling/methods , Disease Resistance/genetics , Viral Load , Gene Expression Regulation
3.
Animals (Basel) ; 14(8)2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38672285

ABSTRACT

White spot disease (WSD) outbreaks pose a significant threat to the Pacific white shrimp (Litopenaeus vannamei) farming industry. The causative agent is the white spot syndrome virus (WSSV). There are no effective treatments for WSD so far. Therefore, understanding the resistance mechanisms of L. vannamei against the WSSV is crucial. C-type lectins (CTLs) are important pattern recognition receptors (PRRs) that promote agglutination, phagocytosis, encapsulation, bacteriostasis, and antiviral infections. This study cloned the C-type lectin domain family 4 member F (LvCLEC4F) from L. vannamei. LvCLEC4F contains a 492 bp open reading frame (ORF) encoding a protein of 163 amino acids, including a carbohydrate recognition domain (CRD). Following a challenge with the WSSV, the expression profile of LvCLEC4F was significantly altered. Using RNA interference (RNAi) technology, it was found that LvCLEC4F promotes WSSV replication and affects the expression levels of genes related to the regulation of apoptosis, signaling and cellular stress response, and immune defense. Meanwhile, the hemolymph agglutination phenomenon in vivo was weakened when LvCLEC4F was knocked down. These results indicated that LvCLEC4F may play an important role in the interaction between L. vannamei and WSSV.

4.
Genes (Basel) ; 14(12)2023 12 15.
Article in English | MEDLINE | ID: mdl-38137042

ABSTRACT

A hybrid offspring of Gannan yak and Jersey cattle, the Jeryak exhibits apparent hybrid advantages over the Gannan yak in terms of production performance and other factors. The small non-coding RNAs known as miRNAs post-transcriptionally exert a significant regulatory influence on gene expression. However, the regulatory mechanism of miRNA associated with muscle development in Jeryak remains elusive. To elucidate the regulatory role of miRNAs in orchestrating skeletal muscle development in Jeryak, we selected longissimus dorsi muscle tissues from Gannan yak and Jeryak for transcriptome sequencing analysis. A total of 230 (DE) miRNAs were identified in the longissimus dorsi muscle of Gannan yak and Jeryak. The functional enrichment analysis revealed a significant enrichment of target genes from differentially expressed (DE)miRNAs in signaling pathways associated with muscle growth, such as the Ras signaling pathway and the MAPK signaling pathway. The network of interactions between miRNA and mRNA suggest that some (DE)miRNAs, including miR-2478-z, miR-339-x, novel-m0036-3p, and novel-m0037-3p, played a pivotal role in facilitating muscle development. These findings help us to deepen our understanding of the hybrid dominance of Jeryaks and provide a theoretical basis for further research on the regulatory mechanisms of miRNAs associated with Jeryak muscle growth and development.


Subject(s)
MicroRNAs , Animals , Cattle/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Muscle, Skeletal/metabolism , Gene Expression Profiling , Muscle Development/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism
5.
Opt Express ; 31(23): 38688-38698, 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-38017967

ABSTRACT

MXenes are a class of two-dimensional layered structure ternary metal carbide or/and nitride materials. Recently, the MXene V2CTx has demonstrated excellent long-term stability, strong saturable absorption, and fast optical-switching capability, used to generate Q-switched and ultrashort pulsed lasers. However, bound-state fiber lasers based on V2CTx have not been reported yet. In this study, V2CTx is combined with a D-shaped fiber to form a saturable absorber device, whose modulation depth is measured to be 1.6%. By inserting the saturable absorber into an Er-doped fiber laser, bound states with different soliton separation and munbers are successfully obtained. Additionally, bound states with a compound soliton structure, such as the (2 + 2)- and (2 + 1)-type, are also realized. Our findings show that V2CTx can be developed as an efficient ultrafast photonics candidate to further understand the complex nonlinear dynamics of bound-state pulses in fiber lasers.

6.
Angew Chem Int Ed Engl ; 62(31): e202305767, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37280162

ABSTRACT

Macrocyclic molecule-based host-guest systems, which provide contributions for the design and construction of functional supramolecular structures, have gained increasing attention in recent years. In particular, platinum(II) metallacycle-based host-guest systems provide opportunities for chemical scientists to prepare novel materials with various functions and structures due to the well-defined shapes and cavity sizes of platinum(II) metallacycles. However, the research on platinum(II) metallacycle-based host-guest systems has been given little attention. In this article, we demonstrate the host-guest complexation between a platinum(II) metallacycle and a polycyclic aromatic hydrocarbon molecule, naphthalene. Taking advantage of metallacycle-based host-guest interactions and the dynamic property of reversible Pt coordination bonds, a [2]rotaxane is efficiently prepared by employing a template-directed clipping procedure. The [2]rotaxane is further applied to the fabrication of an efficient light-harvesting system with multi-step energy transfer process. This work comprises an important supplement to macrocycle-based host-guest systems and demonstrates a strategy for efficient production of well-defined mechanically interlocked molecules with practical values.

7.
Sensors (Basel) ; 23(3)2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36772743

ABSTRACT

The time maintenance accuracy of the navigation constellation determines the user positioning and timing performance. Especially in autonomous operation scenarios, the performance of navigation constellation maintenance time directly affects the duration of constellation autonomous navigation. Among them, the frequency stability of the atomic clock onboard the navigation satellite is a key factor. In order to further improve the stability of the navigation constellation time-frequency system, combined with the development of high-precision inter-satellite link measurement technology, the idea of constructing constellation-level synthetic atomic time has gradually become the development trend of major GNSS systems. This paper gives a navigation constellation time scale generation framework, and designs an improved Kalman plus weights (KPW) time scale algorithm and time-frequency steer algorithm that integrates genetic algorithms. Finally, a 30-day autonomous timekeeping simulation was carried out using the GPS precision clock data provided by CODE, when the sampling interval is 300 s, the Allan deviation of the output time scale is 5.73 × 10-14, a 71% improvement compared with the traditional KPW time scale algorithm; when the sampling interval is 1 day, the Allan deviation is 9.17 × 10-15; when the sampling interval is 1 × 106 s, the Allan deviation is 8.87 × 10-16, a 94% improvement compared with the traditional KPW time scale algorithm. The constellation-level high-precision time scale generation technology proposed in this paper can significantly improve the stability performance of navigation constellation autonomous timekeeping.

8.
Front Nutr ; 9: 1035714, 2022.
Article in English | MEDLINE | ID: mdl-36466402

ABSTRACT

The combined effect of ε-polylysine (PL) and modified atmosphere packaging (MAP; 60% CO2/40% N2) on the bacterial community of greater amberjack filets and their physicochemical properties was evaluated at 4°C. The total viable counts (TVC), psychrotrophic bacterial count, sensory index, texture analysis, and total volatile basic nitrogen (TVB-N) revealed that PL, MAP, and MAP + PL treatment delayed the deterioration of greater amberjack filets. These treatment groups also showed decreased accumulation of biogenic amines. High-throughput 16S rRNA gene sequencing results indicated that these treatments suppressed the growth of Pseudomonas in greater amberjack filets. Furthermore, the MAP + PL treatment group was observed to be more effective than the PL and MAP groups, extending the shelf life of greater amberjack filets by 6 days. This investigation showed that the combination of PL and MAP has the potential to retain the quality and extend the shelf life of greater amberjack.

9.
Sci Prog ; 105(4): 368504221135380, 2022.
Article in English | MEDLINE | ID: mdl-36325728

ABSTRACT

As a unique type of flexible slope fill-retaining structure, reinforced soil-retaining walls have the advantages of convenient construction, broad application conditions, good seismic performance, and high economic benefits. In general, reinforced soil-retaining walls appear at corners due to the restriction in topographic conditions during engineering construction. However, their special structures and stress conditions are usually ignored, thus triggering panel bulging, cracking, and collapse. In this study, an experimental method based on fiber Bragg grating (FBG) sensing technology was proposed for a physical model of reinforced soil-retaining walls. Then, a uniformly distributed load experiment was performed on this model by combining the measurement advantages of intelligent wire-type soil pressure sensors and the flexible characteristics of geotechnical reinforcement materials. The deformation development of this reinforced soil-retaining wall was monitored. Results revealed that before and after the loading of the reinforced soil-retaining wall, the deformation was mainly concentrated above the retaining wall, and the deformation scale at the corners was larger than that in the bilateral linear parts. After loading, the largest force deformation area on the retaining wall was transferred from the corners to the load area. The maximum strain was right beneath the load above the retaining wall, and the peak value at the other layers gradually approached the retaining wall. The experimental results prove that FBG sensing technology is feasible and effective for the whole-process monitoring of reinforced soil-retaining walls and is thus worthy of popularization and application.

10.
Front Genet ; 13: 994806, 2022.
Article in English | MEDLINE | ID: mdl-36226194

ABSTRACT

Long-chain fatty acyl-CoA synthase 1 (ACSL1) plays a vital role in the synthesis and metabolism of fatty acids. The proportion of highly unsaturated fatty acids in beef not only affects the flavor and improves the meat's nutritional value. In this study, si-ACSL1 and NC-ACSL1 were transfected in bovine preadipocytes, respectively, collected cells were isolated on the fourth day of induction, and then RNA-Seq technology was used to screen miRNAs related to unsaturated fatty acid synthesis. A total of 1,075 miRNAs were characterized as differentially expressed miRNAs (DE-miRNAs), of which the expressions of 16 miRNAs were upregulated, and that of 12 were downregulated. Gene ontology analysis indicated that the target genes of DE-miRNAs were mainly involved in biological regulation and metabolic processes. Additionally, KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis identified that the target genes of DE-miRNAs were mainly enriched in metabolic pathways, fatty acid metabolism, PI3K-Akt signaling pathway, glycerophospholipid metabolism, fatty acid elongation, and glucagon signaling pathway. Combined with the previous mRNA sequencing results, several key miRNA-mRNA targeting relationship pairs, i.e., novel-m0035-5p-ACSL1, novel-m0035-5p-ELOVL4, miR-9-X-ACSL1, bta-miR-677-ACSL1, miR-129-X-ELOVL4, and bta-miR-485-FADS2 were screened via the miRNA-mRNA interaction network. Thus, the results of this study provide a theoretical basis for further research on miRNA regulation of unsaturated fatty acid synthesis in bovine adipocytes.

11.
Front Microbiol ; 13: 904358, 2022.
Article in English | MEDLINE | ID: mdl-35711775

ABSTRACT

Viral covert mortality disease (VCMD), also known as running mortality syndrome (RMS), is caused by covert mortality nodavirus (CMNV) and has impacted the shrimp farming industry in Asia and Latin America in recent years. The pathogenic mechanism of CMNV infecting Penaeus vannamei was investigated in this study. In the naturally infected shrimp, histopathological and in situ hybridization (ISH) analysis verified that CMNV infection and severe cellar structural damage occurred in almost all cells of the ommatidium. Under transmission electron microscopic (TEM), vacuolation and necrosis, together with numerous CMNV-like particles, could be observed in the cytoplasm of most cell types of the ommatidium. The challenge test showed that a low CMNV infectious dose caused cumulative mortality of 66.7 ± 6.7% and 33.3 ± 3.6% of shrimp in the 31-day outdoor and indoor farming trials, respectively. The shrimp in the infection group grew slower than those in the control group; the percentage of soft-shell individuals in the infection group (42.9%) was much higher than that of the control group (17.1%). The histopathological and ISH examinations of individuals artificially infected with CMNV revealed that severe cellar damage, including vacuolation, karyopyknosis, and structural failure, occurred not only in the cells of the refraction part of the ommatidium, but also in the cells of the nerve enrichment and hormone secretion zones. And the pathological damages were severe in the nerve cells of both the ventral nerve cord and segmental nerve of the pleopods. TEM examination revealed the ultrastructural pathological changes and vast amounts of CMNV-like particles in the above-mentioned tissues. The differential transcriptome analysis showed that the CMNV infection resulted in the significant down-regulated expression of genes of photo-transduction, digestion, absorption, and growth hormones, which might be the reason for the slow growth of shrimp infected by CMNV. This study uncovered unique characteristics of neurotropism of CMNV for the first time and explored the pathogenesis of slow growth and shell softening of P. vannamei caused by CMNV infection.

12.
Genomics ; 113(6): 3967-3977, 2021 11.
Article in English | MEDLINE | ID: mdl-34601049

ABSTRACT

Long-chain acyl-CoA synthetase 1 (ACSL1) is a member of the acyl-CoA synthetase family that plays a vital role in lipid metabolism. We have previously shown that the ACSL1 gene regulates the composition of unsaturated fatty acids (UFAs) in bovine skeletal muscle, which in turn regulates the fatty acid synthesis and the generation of lipid droplets. Here, we used RNA-Seq to screen circRNAs that regulated the expression of ACSL1 gene and other UFA synthesis-related genes by RNA interference and noninterference in bovine adipocytes. The results of KEGG pathway analysis showed that the parental genes of differentially expressed (DE)-circRNAs were primarily enriched in the adipocytokine signaling pathway. The prediction results showed that novel_circ_0004855, novel_circ_0001507, novel_circ_0001731, novel_circ_0005276, novel_circ_0002060, novel_circ_0005405 and novel_circ_0004254 regulated UFA synthesis-related genes by interacting with the related miRNAs. These results could help expand our knowledge of the molecular mechanisms of circRNAs in the regulation of UFA synthesis in bovine adipocytes.


Subject(s)
MicroRNAs , RNA, Circular , Adipocytes/metabolism , Animals , Cattle , Fatty Acids, Unsaturated/genetics , Fatty Acids, Unsaturated/metabolism , Gene Expression Profiling , Lipid Metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Transcriptome
13.
Front Vet Sci ; 8: 788316, 2021.
Article in English | MEDLINE | ID: mdl-34977220

ABSTRACT

The enzyme long-chain acyl-CoA synthetase 1 (ACSL1) is essential for lipid metabolism. The ACSL1 gene controls unsaturated fatty acid (UFA) synthesis as well as the formation of lipid droplets in bovine adipocytes. Here, we used RNA-Seq to determine lncRNA and mRNA that regulate UFA synthesis in bovine adipocytes using RNA interference and non-interference with ACSL1. The corresponding target genes of differentially expressed (DE) lncRNAs and the DE mRNAs were found to be enriched in lipid and FA metabolism-related pathways, according to GO and KEGG analyses. The differentially expressed lncRNA- differentially expressed mRNA (DEL-DEM) interaction network indicated that some DELs, such as TCONS_00069661, TCONS_00040771, TCONS_ 00035606, TCONS_00048301, TCONS_001309018, and TCONS_00122946, were critical for UFA synthesis. These findings assist our understanding of the regulation of UFA synthesis by lncRNAs and mRNAs in bovine adipocytes.

14.
Sci Rep ; 10(1): 21820, 2020 12 11.
Article in English | MEDLINE | ID: mdl-33311524

ABSTRACT

Segregation distortion is a common phenomenon found in most genetic mapping studies and is an important resource to dissect the mechanism of action in gene loci that cause deviation. Marine animals possess high genetic diversity and genomic heterozygosity, they therefore are ideal model organisms to study segregation distortion induced by selection. In the present study, we constructed a full-sib family of Fenneropenaeus chinensis and exerted high-intensity selection on 10,000 incipient progenies. 2b-RAD method was employed in remaining 273 individuals to develop genome-wide SNPs for segregating analysis and 41,612 SNPs were developed. 50.77% of 32,229 high-quality representative markers deviated from the expected Mendelian ratio. Results showed that most of these distorted markers (91.57%) were influenced at zygotic level. Heterozygote excess (53.07%) and homozygous deletions (41.96%) may both play an important role, sum of which explained 95.03% of distortion after fertilization. However, further results identified highly probable linkage among deleterious alleles, which may account for a considerable portion of heterozygote excess rather than single locus with heterozygote advantage. Results of this study support a major role of deleterious alleles in genetic load, thus in favor of partial dominance hypothesis. It would also offer necessary recommendations for the formulation of breeding strategy in shrimps.


Subject(s)
Genetic Load , Microsatellite Repeats , Penaeidae/genetics , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Selection, Genetic , Animals
15.
PLoS One ; 14(4): e0211182, 2019.
Article in English | MEDLINE | ID: mdl-30958828

ABSTRACT

In order to screen the candidate genes of Fenneropenaeus chinensis related to low-temperature tolerance, this research takes juvenile prawns of F. chinensis (P40) in low temperature stress group (4°C) and normal temperature group (18°C) as experimental materials. The results showed that a total of 127,939 Unigenes with average length of 1,190 bp were obtained by assembly, of which 46% were annotated in the Nr database. A total of 1,698 differentially expressed genes were screened by differential gene expression analysis, of which 920 genes showed up-regulated expression and 778 genes showed down-regulated expression. Both GO and KEGG enrichment analysis revealed that differentially expressed genes were enriched in spliceosomes, ribosomes, bile secretion, ABC transport pathways, and cellular nitrogen compound synthesis. A further in-depth analysis obtained 8 genes that may be associated with low-temperature traits of F. chinensis. Five of them displayed up-regulated expression, including ATP-binding cassette protein C, acid ceramidase, glutathione transferase, C-type lectin and heat shock protein HSP70. The remaining three genes, γ-butyl betaine hydroxylase, ß-hexosaminidase A and long chain fatty acid-CoA ligase displayed down-regulated expression. Eight differentially expressed genes were randomly selected and the real time RT-PCR verification showed that their expression levels were consistent with the sequencing results, demonstrating the accuracy of the sequencing results. The results of this study provide basic data for revealing the molecular mechanisms of F. chinensis in response to low temperature stress and the molecular assisted breeding of F. chinensis in low temperature.


Subject(s)
Acclimatization/genetics , Aquaculture/methods , Cold Temperature/adverse effects , Penaeidae/physiology , Animals , China , Gene Expression Profiling , High-Throughput Nucleotide Sequencing , Metabolic Networks and Pathways/genetics , Seafood , Selective Breeding , Transcriptome/genetics , Exome Sequencing
16.
Fish Shellfish Immunol ; 83: 341-347, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30219386

ABSTRACT

Raf is a member in the Ras/Raf/MAPKK/MAPK signaling transduction pathway. To obtain a better understanding of Raf in the interaction between the Chinese shrimp Fenneropenaeus chinensis and white spot syndrome virus (WSSV), the sequence of cDNA of Raf from F. chinensis (FcRaf) was obtained. The FcRaf gene contained a 2421 bp open reading frame (ORF). The FcRaf shared most characteristic of Raf protein, such as the Raf-like Ras-binding domain (RBD), phorbol esters/diacylglycerol binding domain (C1 domain), and catalytic domain of the serine/threonine kinases, Raf (STKc_Raf). The sequence of functional domains of Raf protein was relatively conserved. The FcRaf mRNA was detected in the tissues of gill, muscle, and hepatopancreas from normal F. chinensis. The mRNA abundance level of FcRaf in the gill was the highest, which was 2.7-fold the level in the hepatopancreas. The expression level of FcRaf was significantly (P < 0.05) up-regulated in the tissues of gill, muscle, and hepatopancreas post WSSV-infection, which suggested that FcRaf might be involved in the interaction between F. chinensis and WSSV. Two SNP loci were identified in the ORF, one of which was a C-T mis-sense mutation, where an Ala was replaced by a Val, and induced the predicted protein secondary structure change. Considering the relatively low MAF (0.07), whether this mis-sense mutation was a detrimental mutation needs further investigation.


Subject(s)
Arthropod Proteins/genetics , Penaeidae/genetics , Penaeidae/virology , White spot syndrome virus 1 , raf Kinases/genetics , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , DNA, Complementary/genetics , Gills/metabolism , Hepatopancreas/metabolism , Muscles/metabolism
17.
Opt Express ; 26(14): 18064-18081, 2018 Jul 09.
Article in English | MEDLINE | ID: mdl-30114085

ABSTRACT

This paper presents a connection mechanism for autonomous self-assembly of segmented space mirrors. Using this connection mechanism, space mirrors can be autonomously captured, positioned, locked and adjusted. The purpose of assembling space mirrors on orbit is to overcome the limits of launch volume and mass and provide a feasibility for future extremely large space telescope in order to improve optical performance to function as monolithic mirrors. In this paper, first, the design details and operation principle of the connection mechanism are presented. Then, based on the initial capture conditions, a double-contact model is investigated. And simulated results of the dynamic and optical performance show that the proposed mechanism overcomes significant alignment errors and is considered suitable for space optical system.

18.
Appl Opt ; 57(15): 4048-4055, 2018 May 20.
Article in English | MEDLINE | ID: mdl-29791378

ABSTRACT

An adjustable bipod flexure (ABF) technique for a large-aperture mirror of a space camera is presented. The proposed flexure mount can decrease the surface distortions caused by the machining error and the assembly error of the mirror assembly (MA) in a horizontal optical testing layout. Through the analysis of the compliance matrix of conventional bipod flexure, the positional relationship between the rotation center and the apex of the flexure is investigated. Then, the principle of the adjustable flexure, known as the trapezoidal switching principle, is proposed based on the analysis result. The structure and application of the flexure are also described. The optical performance of the mirror mounted by the adjustable flexures in different misalignments was performed using finite element methods. The result shows that the astigmatic aberration due to gravity is effectively reduced by adjusting the mount, and the root-mean-square value of the mirror can be minimized with the misalignment between the flexure pivot and the neutral plane minimized. New monolithic bipod flexures, based on the optimal regulating variable Δu according to the measurement results, are manufactured to replace the ABFs to secure the mirror's safety against launch loads. Modal analysis verified the mechanical safety of the MA with respect to the new monolithic flexures.

19.
Fish Shellfish Immunol ; 75: 132-138, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29407618

ABSTRACT

White spot syndrome (WSS) is one of the most damaging phenomena in the culturing of shrimp. To characterize the mechanisms of the molecular responses to WSSV infection in 'Huanghai No. 2'' Fenneropenaeus chinensis, we used next-generation sequencing to observe the transcriptome after oral infection. A total of 108.6 million clean reads were obtained and assembled into 64,103 final unigenes with an average length of 845 bp (N50 = 1534 bp). The assembled unigenes contained 14,263 significant unigenes after BLASTX against the Nr database (E-value cut-off of 10-5). After comparison of digital gene expression data between challenged and control shrimp, a total of 896 DEGs after WSSV infection were identified. Gene pathway analysis indicated that 92, 131 and 142 metabolic pathways were affected at early, peak and late phases respectively. Some pathways were related to the immune response, such as the phagosome, complement and coagulation cascades, the antigen processing and presentation pathway and so on. Many immune-related genes were also identified after pathway analysis. Interestingly, some growth-related genes, such as cathepsin L, myosin regulatory light chain 2 smooth muscle, and alpha-amylase were also differentially expressed after WSSV infection, and the correlation between growth trait and WSSV-resistance trait need further research. The expression patterns of eight DEGs were confirmed by quantitative real-time reverse transcription polymerase chain reaction, and there was good agreement between RNA-seq and qRT-PCR. These data will provide valuable information for characterizing the immune mechanism of the response of shrimp's to WSSV.


Subject(s)
Arthropod Proteins/genetics , Arthropod Proteins/immunology , Penaeidae/genetics , Penaeidae/immunology , Transcriptome/immunology , White spot syndrome virus 1/physiology , Animals , Gene Expression Profiling , Sequence Analysis, RNA
20.
Fish Shellfish Immunol ; 68: 220-231, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28554838

ABSTRACT

MicroRNA (miRNA) is a class of small noncoding RNA, which is involved in the post-transcriptional regulation in all metazoan eukaryotes. MiRNAs might play an important role in the host response to virus infection. However, miRNAs in the aquatic crustacean species were not extensively investigated. To obtain a better understanding of the response of Chinese shrimp Fenneropenaeus chinensis to white spot syndrome virus (WSSV) infection, the sequence and expression profile of miRNAs in the hepatopancreas of WSSV-infected F. chinensis were obtained by the high-throughput Illumina HiSeq 2500 deep sequencing technique. A total number of 129 known miRNAs and 44 putative novel miRNAs were identified from the deep sequencing data. The peak size of miRNAs was 22 nt (37.0%). 25 miRNAs were significantly (P < 0.05) differentially expressed post WSSV infection. Six of the differentially expressed miRNAs were randomly selected for further verification by the real-time RT-PCR technique. The results showed that there was a consistency between the deep sequencing and real-time RT-PCR assay. The target genes of differentially expressed miRNAs were predicted. Each miRNA had 4 target genes on average. The results suggested that some specific miRNAs might be involved in the response of F. chinensis to WSSV infection, and further provided basic information for the investigation of specific miRNAs in F. chinensis.


Subject(s)
Immunity, Innate/genetics , MicroRNAs/immunology , Penaeidae/immunology , Penaeidae/virology , White spot syndrome virus 1/physiology , Animals , Hepatopancreas/immunology , High-Throughput Nucleotide Sequencing , MicroRNAs/genetics , Penaeidae/genetics , Sequence Analysis, RNA
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