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1.
Bing Wen Xi Peng Li Qing Chun Liu Kai Chen Tao Teng Jun Xie 《Systematic parasitology》2017,94(1):73-80
Actinosporean infection of oligochaetes living in the mud of a commercial gibel carp pond with myxosporean disease was studied. Six actinospore types were detected exclusively from the oligochaete Branchiura sowerbyi Beddard with very high prevalence (18%). Five out of the six types were identified as the same actinosporeans described in previous reports, the sixth actinosporean was identified as a new Neoactinomyxum type and described here based on morphological and molecular characterisation. Spore body of the actinospore was globular, much smaller than caudal processes. Three caudal processes were disc-like in apical view, hemispherical in side view, closer together and encircling the spore body. The number of sporoplasm cells was detected as eight in one specimen. The new actinosporean markedly differed from other Neoactinomyxum types in literature having much bigger caudal processes. DNA sequence analyses further confirmed the morphological identification, and revealed the actinosporean described here (KU641392) possessed less than 94% sequence similarity with myxozoans available in the GenBank database. 相似文献
2.
A proteomics approach to identifying novel protein targets involved in erinacine A–mediated inhibition of colorectal cancer cells’ aggressiveness 下载免费PDF全文
Ko‐Chao Lee Hsing‐Chun Kuo Chien‐Heng Shen Chien‐Chang Lu Wen‐Shih Huang Meng‐Chiao Hsieh Cheng‐Yi Huang Yi‐Hung Kuo Yung‐Yu Hsieh Chih‐Chuan Teng Li‐Ya Lee Shui‐Yi Tung 《Journal of cellular and molecular medicine》2017,21(3):588-599
Erinacine A, a major active component of a diterpenoid derivative isolated from Hericium erinaceus mycelium, has been demonstrated to exert anticancer effects. Herein, we present an investigation of the molecular mechanism of erinacine A induction associated with cancer cells’ aggressive status and death. A proteomic approach was used to purify and identify the differentially expressed proteins following erinacine A treatment and the mechanism of its action in apoptotic and the targets of erinacine A. Our results demonstrate that erinacine A treatment of HCT‐116 and DLD‐1 cells increased cell cytotoxicity and reactive oxygen species (ROS) production as well as decreased cell proliferation and invasiveness. Ten differentially displayed proteins were determined and validated in vitro and in vivo between the erinacine A‐treated and untreated groups. In addition, erinacine A time‐dependent induction of cell death and inhibitory invasiveness was associated with sustained phosphorylation of the PI3K/mTOR/p70S6K and ROCK1/LIMK2/Cofilin pathways. Furthermore, we demonstrated that erinacine A–induced HCT‐116 and DLD‐1 cells viability and anti‐invasion properties by up‐regulating the activation of PI3K/mTOR/p70S6K and production of ROS. Experiments involving specific inhibitors demonstrated that the differential expression of cofilin‐1 (COFL1) and profilin‐1 (PROF1) during erinacine A treatment could be involved in the mechanisms of HCT‐116 and DLD‐1 cells death and decreased aggressiveness, which occurred via ROCK1/LIMK2/Cofilin expression, with activation of the PI3K/mTOR/p70S6K signalling pathway. These findings elucidate the mechanism of erinacine A inhibiting the aggressive status of cells by activating PI3K/mTOR/p70S6K downstream signalling and the novel protein targets COF1 and PROF1; this could be a good molecular strategy to limit the aggressiveness of CRC cells. 相似文献
3.
MDM2 is implicated in high‐glucose‐induced podocyte mitotic catastrophe via Notch1 signalling 下载免费PDF全文
Hui Tang Chun‐Tao Lei Chen Ye Pan Gao Cheng Wan Shan Chen Fang‐Fang He Yu‐Mei Wang Hua Su Chun Zhang 《Journal of cellular and molecular medicine》2017,21(12):3435-3444
Podocyte injury and depletion are essential events involved in the pathogenesis of diabetic nephropathy (DN). As a terminally differentiated cell, podocyte is restricted in ‘post‐mitosis’ state and unable to regenerate. Re‐entering mitotic phase will cause podocyte disastrous death which is defined as mitotic catastrophe (MC). Murine double minute 2 (MDM2), a cell cycle regulator, is widely expressed in renal resident cells including podocytes. Here, we explore whether MDM2 is involved in podocyte MC during hyperglycaemia. We found aberrant mitotic podocytes with multi‐nucleation in DN patients. In vitro, cultured podocytes treated by high glucose (HG) also showed an up‐regulation of mitotic markers and abnormal mitotic status, accompanied by elevated expression of MDM2. HG exposure forced podocytes to enter into S phase and bypass G2/M checkpoint with enhanced expression of Ki67, cyclin B1, Aurora B and p‐H3. Genetic deletion of MDM2 partly reversed HG‐induced mitotic phase re‐entering of podocytes. Moreover, HG‐induced podocyte injury was alleviated by MDM2 knocking down but not by nutlin‐3a, an inhibitor of MDM2‐p53 interaction. Interestingly, knocking down MDM2 or MDM2 overexpression showed inhibition or activation of Notch1 signalling, respectively. In addition, genetic silencing of Notch1 prevented HG‐mediated podocyte MC. In conclusion, high glucose up‐regulates MDM2 expression and leads to podocyte MC. Notch1 signalling is an essential downstream pathway of MDM2 in mediating HG‐induced MC in podocytes. 相似文献
4.
Guo Xiaoya Zhu Jian Maehara Akiko Monoly David Samady Habib Wang Liang Billiar Kristen L. Zheng Jie Yang Chun Mintz Gary S. Giddens Don P. Tang Dalin 《Biomechanics and modeling in mechanobiology》2017,16(1):333-344
Biomechanics and Modeling in Mechanobiology - Computational models have been used to calculate plaque stress and strain for plaque progression and rupture investigations. An intravascular... 相似文献
5.
Uncoordinated 51-like kinase 2 (ULK2), a member of the serine/threonine kinase family, plays an essential role in the regulation of autophagy in mammalian cells. Given the role of autophagy in normal cellular homeostasis and in multiple diseases, improved mechanistic insight into this process may result in the development of novel therapeutic approaches. Here, we present evidence that ULK2 associates with karyopherin beta 2 (Kapβ2) for its transportation into the nucleus. We identify a potential PY-NLS motif (774gpgfgssppGaeaapslRyvPY795) in the S/P space domain of ULK2, which is similar to the consensus PY-NLS motif (R/K/H)X
2–5PY. Using a pull-down approach, we observe that ULK2 interacts physically with Kapβ2 both in vitro and in vivo. Confocal microscopy confirmed the co-localization of ULK2 and Kapβ2. Localization of ULK2 to the nuclear region was disrupted by mutations in the putative Kapβ2-binding motif (P794A). Furthermore, in transient transfection assays, the presence of the Kapβ2 binding site mutant (the cytoplasmic localization form) was associated with a substantial increase in autophagy activity (but a decrease in the in vitro serine-phosphorylation) compared with the wild type ULK2. Mutational analysis showed that the phosphorylation on the Ser1027 residue of ULK2 by Protein Kinase A (PKA) is the regulatory point for its functional dissociation from Atg13 and FIP 200, nuclear localization, and autophagy. Taken together, our observations indicate that Kapβ2 interacts with ULK2 through ULK2’s putative PY-NLS motif, and facilitates transport from the cytoplasm to the nucleus, depending on its Ser1027 residue phosphorylation by PKA, thereby reducing autophagic activity. 相似文献
6.
Chun Y. Gao Peggy S. Zelenka 《BioEssays : news and reviews in molecular, cellular and developmental biology》1997,19(4):307-315
Cyclin-dependent kinases and their regulatory subunits, the cyclins, are known to regulate progression through the cell cycle. Yet these same proteins are often expressed in non-cycling, differentiated cells. This review surveys the available information about cyclins and cyclin-dependent kinases in differentiated cells and explores the possibility that these proteins may have important functions that are independent of cell cycle regulation. 相似文献
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9.
Chun Wang Derrick Y. F. Lai Chuan Tong Weiqi Wang Jiafang Huang Chongsheng Zeng 《PloS one》2015,10(5)
Understanding the functional relationship between greenhouse gas fluxes and environmental variables is crucial for predicting the impacts of wetlands on future climate change in response to various perturbations. We examined the relationships between methane (CH4) emission and temperature in two marsh stands dominated by the Phragmites australis and Cyperus malaccensis, respectively, in a subtropical estuarine wetland in southeast China based on three years of measurement data (2007–2009). We found that the Q10 coefficient of CH4 emission to soil temperature (Qs10) from the two marsh stands varied slightly over the three years (P > 0.05), with a mean value of 3.38 ± 0.46 and 3.89 ± 0.41 for the P. australis and C. malaccensis stands, respectively. On the other hand, the three-year mean Qa10 values (Q10 coefficients of CH4 emission to air temperature) were 3.39 ± 0.59 and 4.68 ± 1.10 for the P. australis and C. malaccensis stands, respectively, with a significantly higher Qa10 value for the C. malaccensis stand in 2008 (P < 0.05). The seasonal variations of Q10 (Qs10 and Qa10) differed among years, with generally higher values in the cold months than those in the warm months in 2007 and 2009. We found that the Qs10 values of both stands were negatively correlated with soil conductivity, but did not obtain any conclusive results about the difference in Q10 of CH4 emission between the two tidal stages (before flooding and after ebbing). There were no significant differences in both Qs10 and Qa10 values of CH4 emission between the P. australis stand and the C. malaccensis stands (P > 0.05). Our results show that the Q10 values of CH4 emission in this estuarine marsh are highly variable across space and time. Given that the overall CH4 flux is governed by a suite of environmental factors, the Q10 values derived from field measurements should only be considered as a semi-empirical parameter for simulating CH4 emissions. 相似文献
10.
Matsutake Trade in Yunnan Province,China: An Overview 总被引:1,自引:0,他引:1
Xuefei Yang Jun He Chun Li Jianzhong Ma Yongping Yang Jianchu Xu 《Economic botany》2008,62(3):269-277
Matsutake Trade in Yunnan Province, China: An Overview. Matsutake are economically important wild mushrooms that contribute greatly to rural livelihoods and local economies in many
parts of the northern hemisphere. This paper provides an overview of the matsutake trade in Yunnan province, China, where
increased attention is being given to the sustainable utilization of nontimber forest products. Topics covered include the
distribution, production, and export of matsutake in Yunnan, and the market chain for matsutake in Yunnan, whereby matsutake
are harvested from the wild and exported to Japan within 48 hours. 相似文献