ABSTRACT
RNA viruses including SARS-CoV-2, Ebola virus (EBOV), and Zika virus (ZIKV) constitute a major threat to global public health and society. The interactions between viral genomes and host proteins are essential in the life cycle of RNA viruses and thus provide targets for drug development. However, viral RNA-host protein interactions have remained poorly characterized. Here we applied ChIRP-MS to profile the interactomes of human proteins and the RNA genomes of SARS-CoV-2, EBOV, and ZIKV in infected cells. Integrated interactome analyses revealed interaction patterns that reflect both common and virus-specific host responses, and enabled rapid drug screening to target the vulnerable host factors. We identified Enasidenib as a SARS-CoV-2 specific antiviral agent, and Trifluoperazine and Cepharanthine as broad spectrum antivirals against all three RNA viruses. One Sentence SummaryInteractome analyses of host proteins and the SARS-CoV-2, EBOV, and ZIKV RNA genomes unveil viral biology and drug targets.
ABSTRACT
SUMMARYSARS-CoV-2 is an RNA virus of the Coronaviridae family that is the causal pathogen of the ongoing Coronavirus Disease 2019 pandemic. There are currently no antiviral drugs or vaccines to treat COVID-19, and the failure to identify effective interventions can be blamed on our incomplete understanding of the nature of this virus and its host cell infection process. Here, we experimentally determined structural maps of the SARS-CoV-2 RNA genome in infected human cells and also characterized in vitro refolded RNA structures for SARS-CoV-2 and 6 other coronaviruses. Our in vivo data confirms several structural elements predicted from theoretical analysis and goes much further in revealing many previously unknown structural features that functionally impact viral translation and discontinuous transcription in cells. Importantly, we harnessed our in vivo structure data alongside a deep-learning tool and accurately predicted several dozen functionally related host cell proteins that bind to the SARS-CoV-2 RNA genome, none of which were known previously. Thus, our in vivo structural study lays a foundation for coronavirus RNA biology and indicates promising directions for the rapid development of therapeutics to treat COVID-19.HIGHLIGHTSWe mapped the in vivo structure and built secondary structural models of the SARS-CoV-2 RNA genomeWe discovered functionally impactful structural features in the RNA genomes of multiple coronavirusesWe predicted and validated host cell proteins that bind to the SARS-CoV-2 RNA genome based on our in vivo RNA structural data using a deep-learning toolCompeting Interest StatementThe authors have declared no competing interest.View Full Text
ABSTRACT
OBJECTIVE： To investigate the effects of Kangfuxin liquid on repairing cartilage defect model of knee osteoarthritis （KOA） in rabbits and its mechanism. METHODS： Totally 72 male New Zealand rabbits were selected and randomly divided into model control group and Kangfuxin low-dose， medium-dose， high-dose groups， with 18 rabbits in each group. A cartilage defect model of the medial femoral condyle of the right knee joint in rabbits was established by drilling after anesthesia surgery. Then the rabbits in each group were given medicine via articular cavity immediately. Kangfuxin low-dose， middle-dose and high-dose groups were given 20％， 40％， 80％ Kangfuxin liquid； model control group was given constant volume of normal saline consecutively， 0.2 mL/kg， once every 3 days. At 4th， 8th， 12th week after medication， the wound repair of cartilage defect in rabbits was observed. Immediately after medication and at 4th， 8th， 12th week after medication， repaired tissue of cartilage defect in rabbits was scored histologically with Wakitani scoring standard under light microscope. At 12th week after medication， pathological changes of repaired tissue of cartilage defect in rabbits were observed by Masson staining. The levels of NO， SOD and LPO in joint fluid and PYD in urine of rabbits were detected by ELISA. RESULTS： At 4th， 8th， 12th week after medication， compared with model control group， cartilage defects in rabbits were repaired well in Kangfuxin low-dose， medium-dose and high-dose groups. At 4th， 8th， 12th week after medication， compared with immediately after medication and model control group at same time point， histomorphological score of repairing cartilage defect of knee joint in rabbits decreased significantly in Kangfuxin low-dose， medium-dose and high-dose groups （P＜0.05）. At 12th week after medication， compared with model control group， the histopathology degree of cartilage defect of knee joint in rabbits was significantly alleviated in Kangfuxin low-dose， medium-dose and high-dose groups. At 4th， 8th， 12th week after medication， compared with model control group， the levels of NO and LPO in joint fluid and PYD level in urine were decreased to different extent in Kangfuxin low-dose， medium-dose and high-dose groups， while SOD level was increased to different extent； at 12th week after medication， the difference of each index has statistical significance （P＜0.05 or P＜0.01）. CONCLUSIONS： Kangangxin liquid can significantly repair cartilage defect of KOA cartilage defect model rabbits， the mechanism of which may be associated with increasing the expression of SOD and mediating NO-inhibited chondrocyte apoptosis.