表一、海生所 103 學年專題討論(二) 摘要表
IMB 103 Seminar (II) Abstract form
報告日期/Date:2015 年/year11 月/month25 日/day
班別/學生姓名：
Class/Name:碩二/蔡季航
題目 Title：Identification of orange-spotted grouper (Epinephelus coioides)
interferon regulatory factor 3 involved in antiviral immune response
againstfish RNA virus
作者 Author(s): Youhua Huang, Xiaohong Huang, Jia Cai, Zhengliang
OuYang, Shina Wei, Jingguang Wei,
Qiwei Qin
期刊 Journal name: Fish & Shellfish Immunology
期頁數 Issue and page nos: 42 (2015) 345-352
摘要 Abstract:
Interferon regulatory factor 3 (IRF3) is an important transcription factor
which regulates the expression of interferon (IFN) and IFN-stimulated
genes (ISGs) following virus recognition. In this study, a novel IRF3 gene
was cloned from grouperEpinephelus coioides(EcIRF3) and its effects
against Singapore grouper iridovirus (SGIV) and red spotted grouper
nervous necrosis virus (RGNNV) was investigated. The fulllength of
EcIRF3 cDNA was composed of 2513 bp and encoded a polypeptide of 458
amino acids which shared 82% identity with European seabass
(Dicentrarchus labrax). EcIRF3 contained three conserved domains
including a DNA-binding domain (DBD), an IRF associated domain (IAD)
and a serinerich domain. Expression profile analysis revealed that EcIRF3
was abundant in head kidney, kidney, spleen and gill. Upon different
stimuliin vitro, the transcript of EcIRF3 was significantly up-regulated
after RGNNV infection or treatment with polyinosin-polycytidylic acid
(poly I:C). During SGIV infection, the increase of the EcIRF3
transcription was only detected at the late stage, suggesting that EcIRF3
was differently regulated by different stimuli. Immunefluorescence assay
indicated that thefluorescence signal of EcIRF3 was increased significantly
after infection with RGNNV or treatment with poly I:C, but moderately at
the late stage of SGIV infection. Reporter gene assay showed that EcIRF3
activated zebrafish type I IFN and type III IFN promoterin vitro. The viral
gene transcription and virus production of RGNNV were significantly
decreased in EcIRF3 overexpressing cells. However, the ectopic expression
of EcIRF3 did not affect the gene transcription and virus production of
SGIV. Moreover, the mRNA expression levels of type I IFN and
IFN-inducible genes (MxI, ISG15 and ISG56) were increased in RGNNV
infected EcIRF3 overexpressing cells compared to empty vector
transfected cells. Together, our results demonstrated that IFN immune
response mediated by grouper IRF3 was exerted crucial roles forfish RNA
virus, but not for DNA virus replication.
題目 Title：Antiviral role of grouper STING against iridovirus infection
作者 Author(s): Youhua Huang, Zhengliang Ouyang, Wei Wang, Yepin Yu,
Pengfei Li, Sheng Zhou, Shina Wei, Jingguang Wei, Xiaohong Huang
Qiwei Qin
期刊 Journal name: Fish & Shellfish Immunology
期頁數 Issue and page nos: 47 (2015) 157-167
摘要 Abstract:
Stimulator of interferon genes (STING, also known as MITA, ERIS,
MPYS or TMEM173) has been identified as a central component in the
innate immune response to cytosolic DNA and RNA derived from different
pathogens. However, the detailed role of STING duringfish iridovirus
infection still remained largely unknown. Here, the STING homolog from
grouperEpinephelus coioides(EcSTING) was cloned and its effects on IFN
response and antiviral activity were investigated. The full-length EcSTING
cDNA was composed of 1590 bp and encoded a polypeptide of 409 amino
acids with 80% identity to STING homolog from large yellow croaker.
Amino acid alignment analysis indicated that EcSTING contained 4
predicated transmembrane motifs (TMs) in the N terminal, and a
C-terminal domain (CTD) which consisted of a dimerization domain (DD),
c-di-GMP-binding domain (CBD) and a C-terminal tail (CTT). Expression
profile analysis revealed that EcSTING was abundant in gill, spleen, brain,
skin, and liver. Upon different stimuliin vivo, the EcSTING transcript was
dramatically up-regulated after challenging with Singapore grouper
iridovirus (SGIV), lipopolysaccharide (LPS) and polyinosin-polycytidylic
acid (poly I:C). Reporter gene assay showed that EcSTING activated
ISRE, zebrafish type I IFN and type III IFN promoterin vitro. Mutant
analysis showed that IFN promoter activity was mostly mediated by the
phosphorylation sites at serine residue S379 and S387. Moreover,
EcSTING induced type I and III IFN promoter activity could be impaired
by overexpression of EcIRF3-DN or EcIRF7-DN, suggesting that
EcSTING mediated IFN response in IRF3/IRF7 dependent manner. In
addition, the cytopathic effect (CPE) progression of SGIV infection and
viral protein synthesis was significantly inhibited by overexpression of
EcSTING, and the inhibitory effect was abolished in serine residue S379
and S387 mutant transfected cells. Together, our results demonstrated that
EcSTING might be an important regulator of grouper innate immune
response against iridovirus infection.