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1.
Peng Wang Ronghua Luo Min Zhang Yaqing Wang Tianzhang Song Tingting Tao Zhongyu Li Lin Jin Hongyi Zheng Wenwen Chen Mengqian Zhao Yongtang Zheng Jianhua Qin 《Cell death & disease》2020,11(12)
COVID-19, caused by SARS-CoV-2, is an acute and rapidly developing pandemic, which leads to a global health crisis. SARS-CoV-2 primarily attacks human alveoli and causes severe lung infection and damage. To better understand the molecular basis of this disease, we sought to characterize the responses of alveolar epithelium and its adjacent microvascular endothelium to viral infection under a co-culture system. SARS-CoV-2 infection caused massive virus replication and dramatic organelles remodeling in alveolar epithelial cells, alone. While, viral infection affected endothelial cells in an indirect manner, which was mediated by infected alveolar epithelium. Proteomics analysis and TEM examinations showed viral infection caused global proteomic modulations and marked ultrastructural changes in both epithelial cells and endothelial cells under the co-culture system. In particular, viral infection elicited global protein changes and structural reorganizations across many sub-cellular compartments in epithelial cells. Among the affected organelles, mitochondrion seems to be a primary target organelle. Besides, according to EM and proteomic results, we identified Daurisoline, a potent autophagy inhibitor, could inhibit virus replication effectively in host cells. Collectively, our study revealed an unrecognized cross-talk between epithelium and endothelium, which contributed to alveolar–capillary injury during SARS-CoV-2 infection. These new findings will expand our understanding of COVID-19 and may also be helpful for targeted drug development.Subject terms: Mechanisms of disease, Viral infection 相似文献
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Allopatric isolation in glacial refugia has caused differentiation and speciation in many taxa globally. In this study, we investigated the nuclear and mitochondrial genetic differentiation of the long fingered bat, Myotis capaccinii during the ice ages in south-eastern Europe and Anatolia. The mitochondrial DNA (mtDNA) analyses indicated a suture zone similar to those recorded in other animal species, including bats, suggesting the association of more than one refugium with the region. Contrary to most of the other species where a suture zone was seen in Anatolia, for M. capaccinii the geographical location of the genetic break was in south-eastern Europe. This mitochondrial differentiation was not reflected in the nuclear microsatellites, however, suggesting that the lack of contact during the ice ages did not result in reproductive isolation. Hence taxonomically, the two mitochondrial clades cannot be treated as separate species. 相似文献
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Activation of a UBC4-dependent pathway of ubiquitin conjugation during postnatal development of the rat testis. 总被引:1,自引:0,他引:1
V Rajapurohitam C R Morales M El-Alfy S Lefran?ois N Bedard S S Wing 《Developmental biology》1999,212(1):217-228
During spermatogenesis, germ cells undergo mitotic and meiotic divisions to form haploid round spermatids which mature to functional elongated spermatozoa. During this process there occurs remodeling of cell structure and loss of most of the cytoplasm and a large fraction of cellular proteins. To evaluate the role of the ubiquitin proteolytic system in this protein loss, we measured levels of ubiquitinated proteins and rates of ubiquitin conjugation in extracts of testes from rats of different ages. Endogenous ubiquitin-protein conjugates increased till day 30 and then reached a plateau. In parallel, there was a progressive increase in the rate of conjugation of ubiquitin to proteins in testis extracts from these animals. To test the importance of two major ubiquitin conjugating enzyme families in the conjugation, immunoprecipitation of UBC2 or UBC4 from 10- and 30-day-old testis extracts was carried out and the remaining conjugation activity in supernatants was assayed. Depletion of either enzyme family resulted in decreased conjugation. However, most of the conjugation activity and, more importantly, the increased conjugation during development were UBC4-dependent. Immunocytochemistry demonstrated a marked increase in expression of UBC4 in spermatids, consistent with the UBC4-dependent activation of conjugation seen in vitro. In situ hybridization studies evaluated the contribution of various UBC4 isoforms to this induction. UBC4-1 mRNA was expressed in most cells. UBC4-2 mRNA was restricted to germ cells with high levels of expression in round and elongated spermatids. UBC4-testis had previously been shown to be expressed only in spermatids. Our data suggest that induction of various UBC4 isoforms activates overall conjugation and plays an important role in the cellular remodeling and protein loss occurring during spermatogenesis. 相似文献
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D Hernández S Guerrero M Morales 《Comparative biochemistry and physiology. A, Comparative physiology》1987,87(3):649-656
1. The cardiac pacemaker cells of the frog Caudiverbera caudiverbera are centrally located in the sinus venosus. These cells are rounded, smaller than contractile fibres and have large nuclei. 2. Intracellular recording confirmed the existence of primary and transitional pacemaker cells. 3. Action potentials from primary cells were resistant to blockade by tetrodotoxin (TTX), but were abolished by verapamil suggesting that their bioelectric activity is dependent on a slow inward current. 4. Transitional cells appeared to have two different inward currents contributing to the upstroke: a fast TTX-sensitive and a slow verapamil-sensitive current. 相似文献
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Christian Alvarez Glaucia Gon?alves Barbosa Raquel de Vasconcellos Carvalhaes de Oliveira Bernardina Penarrieta Morales Bodo Wanke Márcia dos Santos Lazéra 《Memórias do Instituto Oswaldo Cruz》2013,108(1):126-129
In this study, we evaluated several techniques for the detection of the yeast form of Cryptococcus in decaying wood and measured the viability of these fungi in environmental samples stored in the laboratory. Samples were collected from a tree known to be positive for Cryptococcus and were each inoculated on 10 Niger seed agar (NSA) plates. The conventional technique (CT) yielded a greater number of positive samples and indicated a higher fungal density [in colony forming units per gram of wood (CFU.g-1) ] compared to the humid swab technique (ST). However, the difference in positive and false negative results between the CT-ST was not significant. The threshold of detection for the CT was 0.05.103 CFU.g-1, while the threshold for the ST was greater than 0.1.103 CFU-1. No colonies were recovered using the dry swab technique. We also determined the viability of Cryptococcus in wood samples stored for 45 days at 25ºC using the CT and ST and found that samples not only continued to yield a positive response, but also exhibited an increase in CFU.g-1, suggesting that Cryptococcus is able to grow in stored environmental samples. The ST.1, in which samples collected with swabs were immediately plated on NSA medium, was more efficient and less laborious than either the CT or ST and required approximately 10 min to perform; however, additional studies are needed to validate this technique. 相似文献
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