共查询到19条相似文献,搜索用时 62 毫秒
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泛素-蛋白酶体系统(ubiquitin proteasome system,UPS)参与了许多精子相关的获能和受精过程,并在获能和受精中起到一定作用.本文综述了精子获能过程中UPS的参与以及发生的相关变化,包括一系列已知的蛋白酶体相关的精子蛋白,并讨论了这些蛋白质与蛋白酶体之间的关系.蛋白酶体抑制剂能显著改变获能并阻止... 相似文献
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泛素蛋白酶体途径(ubiquitin proteasome pathway,UPP)是生物体内最主要的蛋白质降解途径,与多种疾病有关,在生物体内具有十分重要的作用,主要降解错误折叠的、多余的蛋白质。UPP是一个循环途径,其主要作用起始于泛素(ubiquitin,Ub)的激活,是受泛素激活酶(ubiquitin-activating enzyme,E1,酵母菌中是UbE1)、泛素结合酶(ubiquitin-conjugating enzyme,E2,UbE2)、泛素连接酶(ubiquitin-protein ligase,E3,UbE3)和去泛素化酶(deubiquitinating enzymes,DUBs)调控的级联过程,最终使被多聚泛素化(polyubiquitination,polyubiquitination,Poly-Ub)标记的蛋白底物在UPP的蛋白水解核心--26S蛋白酶体内被降解成寡肽,寡肽可以进入新的蛋白循环,Ub则由DUBs去除进入下一个UPP循环。UPP在海鞘类和一些哺乳类体外受精(in vitro fertilization,IVF)过程中具有十分重要的作用,能够参与精子获能和顶体反应(acrosomal reaction,AR),促进精子顶体胞吐,在精卵结合时降解透明带(zona pellucida,ZP)蛋白,辅助精子穿透卵母细胞ZP,促进精子与卵母细胞ZP的融合,从而促使IVF的成功。通过在IVF液中添加一些UPP相关的抗体或抑制剂能够抑制IVF过程中的多精入卵,提高IVF率。作者综述了UPP的主要组成成分及其对IVF的辅助作用及相关抗体的研究进展,以期为今后研究UPP循环在生物体内的作用机制、与生物体内各种疾病的关系、在IVF过程中的作用机制及抑制多精入卵等提供一定的理论依据。 相似文献
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巨噬细胞(macrophage,M_φ)是布鲁菌的主要宿主细胞,为了探明布鲁菌感染与M_φ泛素-蛋白酶体功能之间的关系,本试验在应用蛋白酶体抑制剂Lactacystin与促进剂IFN-γ的基础上,对M_φ感染猪种布鲁菌S2株(Brucella suis,B.suis)后细胞上清中泛素、蛋白酶体及胞内B.suis数量进行了检测。结果显示,IFN-γ与Lactacystin对M_φ泛素的表达均有明显的促进作用,且IFN-γ效果显著优于Lactacystin;其次IFN-γ有效促进了M_φ蛋白酶体的表达,而Lactacystin显著抑制了M_φ蛋白酶体的表达。在此基础上,将B.suis感染不同状态的M_φ,在0.5~24h分别进行胞内B.suis计数,研究表明,一方面B.suis的感染促进了M_φ泛素及蛋白酶体的表达;另一方面,泛素蛋白酶体系统功能的增强,显著降低了B.suis的早期感染,但对于B.suis感染中后期作用不明显,而感染后期抑制M_φ蛋白酶体功能,却可显著降低B.suis的胞内增殖能力。 相似文献
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HeLa细胞中泛素蛋白酶体系统对新城疫病毒复制的影响 总被引:1,自引:0,他引:1
本文主要对细胞的泛素-蛋白酶体系统是否参与新城疫病毒(Newcastle disease virus,NDV)的复制过程进行了研究。用NDV感染HeLa细胞,对细胞样品进行Western blot实验,并检测细胞26S蛋白酶体的三种蛋白水解活性变化。同时使用多种泛素-蛋白酶体系统相关的抑制剂处理细胞并做NDV感染,测定细胞上清中病毒TCID50值,比较药物处理与DMSO处理对病毒增殖的影响。结果表明,HeLa细胞在感染NDV后,细胞内泛素化蛋白水平降低,而26S蛋白酶体的三种蛋白水解活性都显著升高;使用泛素-蛋白酶体系统抑制剂后NDV的增殖受到了明显的抑制,证明NDV在HeLa细胞内的增殖与细胞自身的泛素-蛋白酶体系统关系密切。 相似文献
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泛素-蛋白酶体系统(Ubiquitin-Proteasome System,UPS)是真核细胞内蛋白质降解的2种主要机制之一。在精子发生过程中许多蛋白质和细胞器被降解,UPS在促进精子形成的过程中起着关键作用。在精子发生的减数分裂、顶体生物发生和精子成熟等关键阶段,泛素相关成分(包括去泛素化酶)发挥着积极作用。一般来说,UPS功能障碍会阻止精子发生,这可能会在不同程度上诱发不育。许多UPS成分可以在不同水平上调节精子发生。本文综述了精子发生过程中泛素化修饰研究进展,为后续研究提供新的见解。 相似文献
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Therapeutic treatment targeting one cell type is considered ineffective in remedying any injury to the central nervous system (CNS). Perlecan, a multi‐functional, heparan sulfate proteoglycan, shows diverse effects on distinct cell types, suggesting that it is one of the candidates that can augment the regenerative mechanisms in the injured CNS. Therefore, we examined the functions of perlecan in CNS cells in vitro by using perlecan purified from bovine kidney. Perlecan‐coated cell culture plates, unlike their type I/III collagen‐coated counterparts, did not inhibit the adhesion of neural stem/progenitor cells (NS/PCs) and neurons. The coated perlecan and the perlecan added to the culture medium suppressed astrocyte proliferation; however, perlecan added to the medium promoted NS/PC proliferation. Neurons were promoted to extend their neurites on the perlecan‐coated substrate, and perlecan added to the medium also showed a similar effect. NS/PC proliferation and neurite extension is a major regenerative reaction in CNS injury, whereas excess proliferation of astrocytes cause hypertrophy of glial scars, which repels neurons. Our in vitro study suggests that perlecan is an attractive candidate to promote regenerative mechanisms and to suppress reactions that hamper regenerative processes in cases of CNS injury. 相似文献
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The equine enteric nervous system — Neuron characterization and distribution in adults and juveniles
D. L. Doxey G. T. Pearson E. M. Milne J. S. Gilmour H. K. Chisholm 《Veterinary research communications》1995,19(6):433-449
A study of myenteric and submucosal plexuses was undertaken in the jejunum and ileum of horses and ponies in which no clinical or pathological evidence of intestinal abnormality was apparent. Complete transverse sections of the intestine, stained by a modified haematoxylin and eosin method, were examined using up to 20 sequential sections per animal. Information was gathered from adult, juvenile and fetal equidae. In adults, the longitudinal muscle layers were thinner than the circular muscle layers and the ileum had thicker layers compared to the jejunum. In adults, the submucosal plexus had more neurons per section than the myenteric plexus by mean ratios of 1:3 in the jejunum and 1:1.9 in the ileum. In juveniles, the ratios were respectively 1:1.8 and 1:1.5 and in the fetus 1:2.5 and 1:1.3. The three-dimensional distribution of neurons in both plexuses varied from animal to animal and no consistent pattern was observed. Groups of neurons contained between one and 42 cells per section examined and their length in a cranio-caudal direction varied from 10 to over, 100 µm. There were few statistical differences observed between the cranial, middle and caudal portions of either the jejunum or the ileum when neuron groups or neuron numbers per section were examined in 10 adult animals.Abbreviations H&E
haematoxylin and eosin
Deceased; formerly of the Moredun Research Institute, 408, Gilmerton Road, Edinburgh, EH17 7JH, UK 相似文献
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OBJECTIVE: To identify and describe the occurrence of neurological lesions that could have an effect on lamb mortality. PROCEDURE: The central nervous system was investigated macroscopically (n = 92) and microscopically (n = 72) in lambs dying in the perinatal period during 3 years in flocks of adult Corriedale ewes. The central nervous system was removed intact and samples of cerebral cortex, basal ganglia, thalamus, hippocampus, mesencephalon, cerebellar cortex, medulla oblongata, and cervical spinal cord were scored microscopically for the severity of neuronal dead, cytotoxic and perivascular oedema, and haemorrhage. RESULTS: Neurologic findings between birth and 6 days included haemorrhages in meninges, brain congestion and oedema, neuronal ischemic necrosis, intraparenchymal haemorrhages in medulla oblongata and cervical spinal cord, parasagittal cerebral necrosis, and periventricular leukomalacia. No significant lesions were found in anteparturient deaths or in those aged between 7 and 16 days. Oedema was more severe in the brain than in other regions of the central nervous system. Ischaemic neurons first appeared 24 hours post partum, increased linearly in number between 48 hours and 5 days post partum, and had a laminar distribution in the cerebral cortex, indicating a hypoxic-ischemic encephalopathy. Haemorrhages were most severe in the gray matter of medulla oblongata and cervical spinal cord, suggesting trauma due to instability of atlantoaxialis joint. CONCLUSION: Lesions in the central nervous system can explain most deaths at birth and within 6 days of birth. The lesions were hypoxic-ischemic and appeared to be related to birth injury. 相似文献
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Fumio NAKAMURA Iwao SEKI Ken KOBAYASHI Masakazu TANAKA Shigeharu FUKUNAGA 《Animal Science Journal》2002,73(6):553-556
A simple conventional method of immunohistochemistry (i.e. fixing the frozen sections in cold methanol) was used to determine the immunolocalization of cellular prion protein (PrPc), with good results. In the rat cerebrum, the cytoplasm of neural cells in the cortex and corpus stratum, pia mater, membrane limitans gliae superficialis, choroid plexus and blood vessel wall were immunostained. The formation of network structures of immunostained neural and/or glial fibers in the cerebral cortex was also observed. These immunostained network structures of neural and/or glial fibers were also observed in cultured neural cells. The results suggest that fixation of frozen sections and cultured cells with cold methanol is a useful method for detecting the immunolocalization of PrPc and that PrPc exists in the various components of the central nervous system of the rat. 相似文献
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为研究不同毒力的鸡马立克氏病毒(MDV)在鸡神经系统中的感染规律及其对神经系统的损伤进程,本研究选用不同毒力的血清1型MDV (MDV-1)病毒株感染4日龄的SPF鸡,在接毒后1 d、3 d、5 d、7 d、10 d、14 d、17 d、21 d、25 d、28 d和35 d动态检测病毒载量的变化,并对感染后5 d和21 d的不同病毒株感染鸡的脑部和坐骨神经进行组织病理学观察。结果显示,MDV-1强毒株在SPF鸡脑部的复制能力显著高于弱毒株(p<0.05);特超强病毒株BS在脑组织中出现的时间最早,早期复制最快。但不同毒力的MDV-1株在坐骨神经处的复制能力与其毒力无直接的关系。组织病理学观察显示,在感染早期MDV-1强毒株对SPF鸡脑组织的损伤强于弱毒株;在感染后21 d,强毒株和弱毒株造成的脑部损伤存在明显的不同;而在坐骨神经处,强毒株造成的损伤明显强于弱毒株。本研究揭示了不同MDV病毒株在SPF鸡脑和坐骨神经的复制动力学特征和组织病理学特征,为MDV-1在宿主神经系统中的感染、增殖及造成的损伤提供了实验依据。 相似文献
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Suppurative infections are typically caused by pyogenic bacteria, and are characterised by the formation of purulent exudates (pus). These infections may occur anywhere in the body and are particularly life‐threatening when pertaining to the central nervous system (CNS). Suppurative infections of the CNS may be due to trauma, local extension of disease, and haematogenous spread. In horses, suppurative infections are an important cause of morbidity and mortality, but only infrequently involve the CNS. The gross morphology of suppurative inflammation is described as phlegmon, abscess and empyema, with each form having characteristic morphological features that may be identified during advanced imaging of the CNS. In horses with known or suspected suppurative infection of the CNS, imaging may be performed to reduce diagnostic uncertainty, determine prognosis, or to describe the character and extent of the disease to guide case management. 相似文献
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Foley JE Leutenegger C 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(5):438-444
Feline infectious peritonitis (FIP) is a common cause of death in cats. Management of this disease has been hampered by difficulties identifying the infection and determining the immunological status of affected cats and by high variability in the clinical, pathological, and immunological characteristics of affected cats. Neurological FIP, which is much more homogeneous than systemic effusive or noneffusive FIP, appears to be a good model for establishing the basic features of FIP immunopathogenesis. Very little information is available about the immunopathogenesis of neurologic FIP, and it is reasonable to use research from the well-characterized mouse hepatitis virus (MHV) immune-mediated encephalitis system, as a template for FIP investigation, and to contrast findings from the MHV model with those of FIP. It is expected that the immunopathogenic mechanisms will have important similarities. Such comparative research may lead to better understanding of FIP immunopathogenesis and rational prospects for management of this frustrating disease. 相似文献