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881.
882.
Yun-Xia Luan Yingying Cui Wan-Jun Chen Jian-Feng Jin Ai-Min Liu Cheng-Wang Huang Mikhail Potapov Yun Bu Shuai Zhan Feng Zhang Sheng Li 《Molecular ecology resources》2023,23(1):273-293
The collembolan Folsomia candida Willem, 1902, is widely distributed throughout the world and has been frequently used as a test organism in soil ecology and ecotoxicology studies. However, it is questioned as an ideal “standard” because of differences in reproductive modes and cryptic genetic diversity between strains from various geographical origins. In this study, we obtained two high-quality chromosome-level genomes of F. candida, for a parthenogenetic strain (named FCDK, 219.08 Mb, 25,139 protein-coding genes) and a sexual strain (named FCSH, 153.09 Mb, 21,609 protein-coding genes), reannotated the genome of the parthenogenetic strain reported by Faddeeva-Vakhrusheva et al. in 2017 (named FCBL, 221.7 Mb, 25,980 protein-coding genes) and conducted comparative genomic analyses of the three strains. High genome similarities between FCDK and FCBL based on synteny, genome architecture, mitochondrial and nuclear gene sequences suggest that they are conspecific. The seven chromosomes of FCDK are each 25%–54% larger than the corresponding chromosomes of FCSH, showing obvious repetitive element expansions and large-scale inversions and translocations but no whole-genome duplication. The strain-specific genes, expanded gene families and genes in nonsyntenic chromosomal regions identified in FCDK are highly related to the broader environmental adaptation of parthenogenetic strains. In addition, FCDK has fewer strain-specific microRNAs than FCSH, and their mitochondrial and nuclear genes have diverged greatly. In conclusion, FCDK/FCBL and FCSH have accumulated independent genetic changes and evolved into distinct species after 10 million years ago. Our work provides important genomic resources for studying the mechanisms of rapidly cryptic speciation and soil arthropod adaptation to soil ecosystems. 相似文献
883.
884.
Brunna Muniz Rodrigues Falcão Joyce Galvão de Souza Ana Yasha Ferreira de La Salles Luan Nascimento Batista Ediane Freitas Rocha João Augusto Rodrigues Alves Diniz Annielle Regina Fonseca Fernandes José Rômulo Soares dos Santos Danilo José Ayres de Menezes Gildenor Xavier Medeiros 《Journal of medical primatology》2020,49(3):153-157
885.
Jiaqi Liu Wenjie Luan Yong Zhang Jianying Gu Yuedong Shi Yanwen Yang Zihao Feng Fazhi Qi 《Biochemical and biophysical research communications》2018,495(4):2630-2636
Histone deacetylase 6 (HDAC6) plays an important role in oncogenic transformation and cancer metastasis. Our previous study has demonstrated that HDAC6 was highly expressed in melanoma cells, and contributed to the proliferation and metastasis of melanoma cells. However, the underlying mechanism of HDAC6 in melanoma metastasis and progression remains largely unclear. In this study, we reported that HDAC6 directly interacted with Tyrosine-protein phosphatase non-receptor type 1 (PTPN1) by performing co-immunoprecipitation (Co-IP) combined with liquid chromatography tandem mass spectrometry (LC-MS/MS). HDAC6 increased the protein level of PTPN1 independent of histone modifying activity. In addition, PTPN1 promoted proliferation, colony formation and migration while decreased apoptosis of melanoma cells through activating extracellular signal-regulated kinase 1/2 (ERK1/2). Furthermore, we found that matrix metallopeptidase 9 (MMP9) was increased by HDAC6/PTPN1/ERK1/2 axis, which might serve as a mechanism for melanoma invasion and metastasis. In conclusion, HDAC6 might enhance aggressive melanoma cells progression via interacting with PTPN1, which was independent of its histone modifying activity. 相似文献
886.
Dielectric Elastomer Actuators (DEA) have a wide application prospect in the area of robot due to its merits. The aim of this paper is to improve the displacement of cone DEA and to make full use of the large-strain advantage of elastomer, as well as to reduce the volume and mass of actuator. After presenting the manufacturing process and working principle of cone DEA, it is analyzed that negative stiffness preload can enlarge the displacement of actuator significantly. Then a half-diamond mechanism is analyzed using double-slider model to implement a negative stiffness preload. Two points from force-displacement curves, foff and fon of elastomer with voltage on and off, are selected as two working equilibrium positions of actuator to calculate the parameters of the preload mechanism, hereby the negative stiffness mechanism is realized. Displacement experiments show that the cone DEA has a displacement of 20 mm under voltage 7541V and experimental results agree well with analytical results. Since the initial displacement is very small, so the large-strain advantage of elastomer is used for improving the displacement of actuator. In addition, the force outputs of the actuator when voltage is on and off are acquired, which shows actuator has a maximal force ability of 1.6 N. 相似文献
887.
Pei Wang Meiting Chen Yaying Hou Jun Luan Ruili Liu Liuqing Chen Min Hu Qiuliyang Yu 《Aging cell》2023,22(10):e13965
Nicotinamide adenine dinucleotide (NAD+) level has been associated with various age-related diseases and its pharmacological modulation emerges as a potential approach for aging intervention. But human NAD+ landscape exhibits large heterogeneity. The lack of rapid, low-cost assays limits the establishment of whole-blood NAD+ baseline and the development of personalized therapies, especially for those with poor responses towards conventional NAD+ supplementations. Here, we developed an automated NAD+ analyzer for the rapid measurement of NAD+ with 5 μL of capillary blood using recombinant bioluminescent sensor protein and automated optical reader. The minimal invasiveness of the assay allowed a frequent and decentralized mapping of real-world NAD+ dynamics. We showed that aerobic sport and NMN supplementation increased whole-blood NAD+ and that male on average has higher NAD+ than female before the age of 50. We further revealed the long-term stability of human NAD+ baseline over 100 days and identified major real-world NAD+-modulating behaviors. 相似文献
888.
Herbaceous peony (Paeonia lactiflora Pall.), as a high-end cut flower in the international market, has high ornamental and medicinal values. But in Northern China, drought is a major environmental factor influencing the growth and development of P. lactiflora. Quantitative real-time polymerase chain reaction (qRT-PCR) can evaluate gene expression levels under different stress conditions, and stable internal reference is the key for qRT-PCR. At present, there is no systematic screening of internal reference for correcting gene expressions of P. lactiflora in response to drought stress. In this study, 10 candidate genes [ubiquitin (UBQ2), UBQ1, elongation factor 1-α (EF-1α), Histidine (His), eukaryotic initiation factor (eIF), tubulin (TUB), actin (ACT), UBQ3, ACT2, RNA polymerase II (RNA Pol II)] were chosen, and 4 analysis methods were used to compare the stabilities for these 10 genes coping with drought stress. Due to the difference of operation methods, the results of different analysis were distinct, and the final comprehensive analysis indicated that EF-1α was a relatively stable internal reference gene for P. lactiflora under drought stress. Also, UBQ1 and UBQ2 were the best reference gene combination according to GeNorm analysis. This study will lay a foundation for screening the key genes of P. lactiflora in response to drought stress. 相似文献
889.
890.
BioMetals - Previous researches have been conducted to study the associations of trace elements on Type 2 diabetes (T2D) risk. The present study focuses on the evaluation of potential associations... 相似文献