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21.
Terrence Tsz-Tai Yuen Jasper Fuk-Woo Chan Bingpeng Yan Cynthia Cheuk-Ying Shum Yuanchen Liu Huiping Shuai Yuxin Hou Xiner Huang Bingjie Hu Yue Chai Chaemin Yoon Tianrenzheng Zhu Huan Liu Jialu Shi Jinjin Zhang Jian-Piao Cai Anna Jinxia Zhang Jie Zhou Feifei Yin Shuofeng Yuan Bao-Zhong Zhang Hin Chu 《International journal of biological sciences》2022,18(12):4714
The Coronavirus Disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the biggest public health challenge the world has witnessed in the past decades. SARS-CoV-2 undergoes constant mutations and new variants of concerns (VOCs) with altered transmissibility, virulence, and/or susceptibility to vaccines and therapeutics continue to emerge. Detailed analysis of host factors involved in virus replication may help to identify novel treatment targets. In this study, we dissected the metabolome derived from COVID-19 patients to identify key host factors that are required for efficient SARS-CoV-2 replication. Through a series of metabolomic analyses, in vitro, and in vivo investigations, we identified ATP citrate lyase (ACLY) as a novel host factor required for efficient replication of SARS-CoV-2 wild-type and variants, including Omicron. ACLY should be further explored as a novel intervention target for COVID-19. 相似文献
22.
Solomon A. Sloat Luke M. Noble Annalise B. Paaby Max Bernstein Audrey Chang Taniya Kaur John Yuen Sophia C. Tintori Jacqueline L. Jackson Arielle Martel Jose A. Salome Correa Lewis Stevens Karin Kiontke Mark Blaxter Matthew V. Rockman 《Ecology and evolution》2022,12(7)
Factors shaping the distribution and abundance of species include life‐history traits, population structure, and stochastic colonization–extinction dynamics. Field studies of model species groups help reveal the roles of these factors. Species of Caenorhabditis nematodes are highly divergent at the sequence level but exhibit highly conserved morphology, and many of these species live in sympatry on microbe‐rich patches of rotten material. Here, we use field experiments and large‐scale opportunistic collections to investigate species composition, abundance, and colonization efficiency of Caenorhabditis species in two of the world''s best‐studied lowland tropical field sites: Barro Colorado Island in Panamá and La Selva in Sarapiquí, Costa Rica. We observed seven species of Caenorhabditis, four of them known only from these collections. We formally describe two species and place them within the Caenorhabditis phylogeny. While these localities contain species from many parts of the phylogeny, both localities were dominated by globally distributed androdiecious species. We found that Caenorhabditis individuals were able to colonize baits accessible only through phoresy and preferentially colonized baits that were in direct contact with the ground. We estimate the number of colonization events per patch to be low. 相似文献
23.
The psychrophile Clostridium sp. strain 69 contains a thermolabile triose phosphate isomerase which is inactivated rapidly in vitro and in vivo at 32 C. 相似文献
24.
25.
E. M. Slominska A. Yuen L. Osman J. Gebicki M. H. Yacoub R. T. Smolenski 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):863-866
Following discovery of NAD+-dependent reactions that control gene expression, cytoprotection, and longevity, there has been a renewed therapeutic interest in precursors, such as nicotinamide and its derivatives. We tested 20 analogues of nicotinamide for their ability to protect endothelial cells from peroxynitrite stress and their effect on poly (ADP-ribose) polymerase (PARP) activity. Several nicotinamide derivatives protected endothelial cells from peroxynitrite-induced depletion of cellular NAD+ and ATP concentrations, but only some of these compounds inhibited PARP. We conclude that some nicotinamide derivatives provide protection of endothelial cells against peroxynitrite-induced injury independent of inhibition of PARP activity. Preservation of the NAD+ pool was a common effect of these compounds. 相似文献
26.
T. Borkowski C. Orlewska E. M. Slominska A. Yuen M. Lipinski I. Rybakowska 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):867-871
Because mutation of AMP deaminase 1 gene leading to reduced AMP deaminase activity may result in protection of cardiac function in patients with heart disease, inhibitors of AMP deaminase (AMPD) may have therapeutic applications. This study evaluated the effect of a specific inhibitor of AMP deaminase 3-[2-(3-carboxy-4-bromo-5,6,7,8-tetrahydronaphthyl)ethyl]-3,6,7,8-tetrahydroimidazo [4,5-d][1,3]diazepin-8-ol (AMPDI) on the isolated human enzyme and on nucleotide catabolism in rat cardiomyocytes. AMPDI effectively inhibited isolated human AMPD with an IC 50 = 0.5 μ M. AMPDI was much less effective with isolated cardiomyocytes (IC 50 = 0.5 mM). AMPDI is a very effective inhibitor of AMPD that despite lower efficiency in the cell system examined could be useful for in vivo studies. 相似文献
27.
28.
Christopher I Keeling Macaire MS Yuen Nancy Y Liao T Roderick Docking Simon K Chan Greg A Taylor Diana L Palmquist Shaun D Jackman Anh Nguyen Maria Li Hannah Henderson Jasmine K Janes Yongjun Zhao Pawan Pandoh Richard Moore Felix AH Sperling Dezene P W Huber Inanc Birol Steven JM Jones Joerg Bohlmann 《Genome biology》2013,14(3):R27
29.
Xiu L. Chen Nicklaus L. J. E. Wee Kum C. Hiong Jasmine L. Y. Ong You R. Chng Biyun Ching Wai P. Wong Shit F. Chew Yuen K. Ip 《PloS one》2013,8(12)
The swamp eel, Monopterus albus, can survive in high concentrations of ammonia (>75 mmol l−1) and accumulate ammonia to high concentrations in its brain (∼4.5 µmol g−1). Na+/K+-ATPase (Nka) is an essential transporter in brain cells, and since NH4
+ can substitute for K+ to activate Nka, we hypothesized that the brain of M. albus expressed multiple forms of Nka α-subunits, some of which might have high K+ specificity. Thus, this study aimed to clone and sequence the nka α-subunits from the brain of M. albus, and to determine the effects of ammonia exposure on their mRNA expression and overall protein abundance. The effectiveness of NH4
+ to activate brain Nka from M. albus and Mus musculus was also examined by comparing their Na+/K+-ATPase and Na+/NH4
+-ATPase activities over a range of K+/NH4
+ concentrations. The full length cDNA coding sequences of three nkaα (nkaα1, nkaα3a and nkaα3b) were identified in the brain of M. albus, but nkaα2 expression was undetectable. Exposure to 50 mmol l−1 NH4Cl for 1 day or 6 days resulted in significant decreases in the mRNA expression of nkaα1, nkaα3a and nkaα3b. The overall Nka protein abundance also decreased significantly after 6 days of ammonia exposure. For M. albus, brain Na+/NH4
+-ATPase activities were significantly lower than the Na+/K+-ATPase activities assayed at various NH4
+/K+ concentrations. Furthermore, the effectiveness of NH4
+ to activate Nka from the brain of M. albus was significantly lower than that from the brain of M. musculus, which is ammonia-sensitive. Hence, the (1) lack of nkaα2 expression, (2) high K+ specificity of K+ binding sites of Nkaα1, Nkaα3a and Nkaα3b, and (3) down-regulation of mRNA expression of all three nkaα isoforms and the overall Nka protein abundance in response to ammonia exposure might be some of the contributing factors to the high brain ammonia tolerance in M. albus. 相似文献
30.
Yiu-fai Cheung Wei Yu Daniel Ka-leung Cheuk Frankie Wai-tsoi Cheng Janet Yee-kwan Yang Jeffrey Ping-wa Yau Karin Ka-huen Ho Chi-kong Li Rever Chak-ho Li Hui-leung Yuen Alvin Siu-cheung Ling Vivian Wing-yi Li Wai-keung Wong Kwong-cheong Tsang Godfrey Chi-fung Chan 《PloS one》2013,8(10)