• 한국콘텐츠학회논문지
• /
• 제19권11호
• /
• pp.632-643
• /
• 2019

최근 지구 기후의 변화, 해외 여행객의 증가 및 국가 간 물류 이동의 증가 등과 같은 요인으로 인해 모기와 같은 절지동물이 매개하는 아보바이러스(arthropod-borne virus, arbovirus) 감염으로 인한 대규모의 피해가 전 세계적으로 끊임없이 발생하고 있다. 그 중에서도 플라비바이러스 속에 해당하는 지카 바이러스와 뎅기바이러스에 의한 피해가 대표적이다. 본 연구에서는 다양한 생물정보학 데이터베이스를 바탕으로 지카 바이러스 및 뎅기 바이러스가 숙주 감염에 필수적인 기능을 수행하는 외피 단백질에 대한 심층적인 분석을 수행했다. 외피 단백질을 구성하는 도메인들에 대한 분석을 통해 도메인의 종류, 위치 및 기능을 파악했으며 각 도메인별 상동성을 분석했다. 이로부터 낮은 상동성을 보이는 도메인인 EDIII를 도출하였으며, EDIII를 구성하는 펩타이드에 대한 상동성 및 면역원성 분석과 3차원 구조 모델링을 수행했다. 더 나아가 이들이 갖는 생물학적 의미와 활용 방안에 대해 논의했다.

• Journal of Microbiology and Biotechnology
• /
• 제30권11호
• /
• pp.1651-1658
• /
• 2020

Since Zika virus (ZIKV) was first detected in Uganda in 1947, serious outbreaks have occurred globally in Yap Island, French Polynesia and Brazil. Even though the number of infections and spread of ZIKV have risen sharply, the pathogenesis and replication mechanisms of ZIKV have not been well studied. ZIKV, a recently highlighted Flavivirus, is a mosquito-borne emerging virus causing microcephaly and the Guillain-Barre syndrome in fetuses and adults, respectively. ZIKV polyprotein consists of three structural proteins named C, prM and E and seven nonstructural proteins named NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5 in an 11-kb single-stranded positive sense RNA genome. The function of individual ZIKV genes on the host innate immune response has barely been studied. In this study, we investigated the modulations of the NF-κB promoter activity induced by the MDA5/RIG-I signaling pathway. According to our results, two nonstructural proteins, NS2A and NS4A, dramatically suppressed the NF-κB promoter activity by inhibiting signaling factors involved in the MDA5/RIG-I signaling pathway. Interestingly, NS2A suppressed all components of MDA5/RIG-I signaling pathway, but NS4A inhibited most signaling molecules, except IKKε and IRF3-5D. In addition, both NS2A and NS4A downregulated MDA5-induced NF-κB promoter activity in a dosedependent manner. Taken together, our results suggest that NS2A and NS4A signifcantly antagonize MDA5/RIG-I-mediated NF-κB production, and these proteins seem to be controlled by different mechanisms. This study could help understand the mechanisms of how ZIKV controls innate immune responses and may also assist in the development of ZIKV-specific therapeutics.

• Genomics & Informatics
• /
• 제14권3호
• /
• pp.104-111
• /
• 2016

Zika virus (ZIKV) is a mosquito borne pathogen, belongs to Flaviviridae family having a positive-sense single-stranded RNA genome, currently known for causing large epidemics in Brazil. Its infection can cause microcephaly, a serious birth defect during pregnancy. The recent outbreak of ZIKV in February 2016 in Brazil realized it as a major health risk, demands an enhanced surveillance and a need to develop novel drugs against ZIKV. Amodiaquine, prochlorperazine, quinacrine, and berberine are few promising drugs approved by Food and Drug Administration against dengue virus which also belong to Flaviviridae family. In this study, we performed molecular docking analysis of these drugs against nonstructural 3 (NS3) protein of ZIKV. The protease activity of NS3 is necessary for viral replication and its prohibition could be considered as a strategy for treatment of ZIKV infection. Amongst these four drugs, berberine has shown highest binding affinity of -5.8 kcal/mol and it is binding around the active site region of the receptor. Based on the properties of berberine, more similar compounds were retrieved from ZINC database and a structure-based virtual screening was carried out by AutoDock Vina in PyRx 0.8. Best 10 novel drug-like compounds were identified and amongst them ZINC53047591 (2-(benzylsulfanyl)-3-cyclohexyl-3H-spiro[benzo[h]quinazoline-5,1'-cyclopentan]-4(6H)-one) was found to interact with NS3 protein with binding energy of -7.1 kcal/mol and formed H-bonds with Ser135 and Asn152 amino acid residues. Observations made in this study may extend an assuring platform for developing anti-viral competitive inhibitors against ZIKV infection.

• Entomological Research
• /
• 제48권5호
• /
• pp.439-447
• /
• 2018

Adult mosquito surveillance was conducted from 2013 through 2014 at four cattle sheds, a wild bird refuge, and two residential areas located in Gyeongnam Province in the Republic of Korea. Adult mosquitoes were collected in black light traps from April 1, through November 30. Mosquito surveillance was conducted to figure out population densities of vector mosquitoes, possibly invaded mosquitoes and identify various virus infections at the selected sites. A total of 107,466 females comprising 14 species and 7 genera were collected from 2013 to 2014. The most common species collected were Culex tritaeniorhynchus Giles (63.8%), Anopheles sinensis s.l. (18.9%), Aedes vexans nipponii (Theobald) (7.7%), and Culex pipiens Coquillett (5.1%). Trap indices (TIs) varied widely for species over their range, due to geographical distribution and degree of association with rural and urban communities. The most collected An. sinensiss.l. and Cx. tritaeniorhynchus appeared at a cow shed in Hapcheon (TI 347.5) and a pigsty in Daejeo-1-dong, Busan (TI 1,040.8), respectively, due in part to their situation near breeding sites such as rice paddies. The bi-weekly population densities for mosquito species were variable for each of the years, apparently as a result of variable annual weather conditions. None of the mosquito species collected tested for the flavivirus including Japanese Encephalitis Virus, West Nile Virus, Dengue Virus, and Zika Virus infections by polymerase chain reaction (PCR) assay were positive.

• Journal of Microbiology and Biotechnology
• /
• 제29권10호
• /
• pp.1665-1674
• /
• 2019

Zika virus (ZIKV) is a mosquito-transmitted, emerging Flavivirus that causes Guillain-$Barr{\acute{e}}$ syndrome and microcephaly in adults and fetuses, respectively. Since ZIKV was first isolated in 1947, severe outbreaks have occurred at various places worldwide, including Yap Island in 2007, French Polynesia in 2013, and Brazil in 2015. Although incidences of ZIKV infection and dissemination have drastically increased, the mechanisms underlying the pathogenesis of ZIKV have not been sufficiently studied. In addition, despite extensive research, the exact roles of individual ZIKV genes in the viral evasion of the host innate immune responses remain elusive. Besides, it is still possible that more than one ZIKV-encoded protein may negatively affect type I interferon (IFN) induction. Hence, in this study, we aimed to determine the modulations of the IFN promoter activity, induced by the MDA5/RIG-I signaling pathway, by over-expressing individual ZIKV genes. Our results show that two nonstructural proteins, NS2A and NS4A, significantly down-regulated the promoter activity of IFN-${\beta}$ by inhibiting multiple signaling molecules involved in the activation of IFN-${\beta}$. Interestingly, while NS2A suppressed both full-length and constitutively active RIG-I, NS4A had inhibitory activity only on full-length RIG-I. In addition, while NS2A inhibited all forms of IRF3 (full-length, regulatory domain-deficient, and constitutively active), NS4A could not inhibit constitutively active IRF3-5D. Taken together, our results showed that NS2A and NS4A play major roles as antagonists of MDA5/RIG-I-mediated IFN-${\beta}$ induction and more importantly, these two viral proteins seem to inhibit induction of the type I IFN responses in differential mechanisms. We believe this study expands our understanding regarding the mechanisms via which ZIKV controls the innate immune responses in cells and may pave the way to development of ZIKV-specific therapeutics.

• 대한임상검사과학회지
• /
• 제54권2호
• /
• pp.142-148
• /
• 2022

이 조사는 전북지역에서 일본뇌염, 말라리아, 웨스트나일병, 지카바이러스, 황열의 매개체 모기에 대해 조사되었다. 2021년 3월부터 12월까지 매월 2회 모기류를 채집하여 감염병 매개체 발생빈도와 병원체를 조사 감시한 결과 전체 채집 개체수는 7속 15종으로 15,975마리가 채집되었다. 환경별로 완주 축사에서 9,116마리(trap index: TI, 506.4)로 가장 많이 채집되었으며 철새도래지, 전주도심의 순서로 채집되었다. 군산 철새도래지에서는 철새보호구역의 갈대숲에서는 3217마리(TI, 178.7), 남자화장실에서 356마리(TI, 19.7), 여자화장실에서 1,948마리(TI, 108.2) 채집되었다. 전주시내에서는 덕진공원에서 677마리(TI, 37.6), 덕진구청에서 358마리(TI, 19.8), 전북대에서 303마리(TI, 16.8)가 채집되었다. 군산 철새도래지에서는 여자화장실, 전주 도심에서는 덕진공원에서 가장 많은 개체수가 채집되었다. 병원체 검사 결과는 모두 음성이었다. 이 연구결과는 전북지역 모기에 의한 질병대책 전북지역 모기매개감염병에 대한 기초자료의 근거를 제공해 준다.

• 미생물학회지
• /
• 제46권2호
• /
• pp.140-147
• /
• 2010

일본뇌염바이러스(Japanese encephalitis virus)는 모기 매개성 플라비바이러스에 속하며, 주로 동남아시아 지역에서 유행성 바이러스성 뇌염을 일으킨다. 일본뇌염바이러스는 외피를 가진 작은 바이러스로서, 양성가닥 RNA 게놈을 가지고 있다. 감염성을 띤 바이러스 입자는 capsid (C), membrane (M; prM 전구체로부터 생성), 및 envelope (E)과 같은 3개의 구조단백질로 이루어져 있다. 본 연구에서는 일본뇌염바이러스 생산과 정에 M 단백질의 N-말단부위에 위치한 극성 아미노산 잔기의 역할을 분석하였다. 일본뇌염바이러스의 infectious cDNA를 활용하여, M 단백질의 $E^9$와 $K^{15}K^{16}E^{17}$ 잔기를 알라닌으로 치환시킨 2개의 mutant cDNA (Mm1과 Mm2)를 각각 제작하였다. 각각의 cDNA로부터 합성된 mutant RNA를 세포에 트랜스펙션시킴으로써, 비록 세포 내에 축적된 3개의 구조단백질양은 변화가 없으나, 이들 세포로부터 생산된 바이러스의 양은 Mm2 RNA의 경우 ~1,000배 감소됨을 관찰하였다. 흥미롭게도, Mm2 RNA로부터 발현된 mutant M 단백질은 wild-type M 단백질을 인지하는 항혈청에는 반응하지 않았으나, mutant M 단백질을 항원으로 제작된 항혈청에는 반응하는 것을 알 수 있었다. 본 실험결과는 일본뇌염바이러스 M 단백질을 구성하는 3개의 극성 아미노산 잔기($K^{15}K^{16}E^{17}$)가 바이러스의 생산과정에 관여한다는 것을 암시한다. 앞으로, wild-type 또는 mutant M 단백질(Mm2)을 인식하는 2개의 항혈청은 이 단백질의 기능연구에 유용한 재료로 사용될 것으로 기대된다.