Molecular cloning and functional characterization of porcine DNA-dependent activator of IFN-regulatory factors (DAI).
The DNA-dependent activator of IFN-regulatory factors (DAI) is a recently identified DNA sensor for intracellular DNA that triggers a signal for the production of type I IFN. Here we report the cloning and characterization of porcine DAI (poDAI). The full-length of poDAI encodes 439 amino acids, contains two N-terminal DNA-binding domains and shows similarity to mouse, rat, dog, monkey, human, horse and cattle counterparts ranging from 44% to 67%. poDAI mRNA expression was mainly detected in spleen, lung, kidney and small intestine. Over-expression of poDAI activated transcription factors IRF3 and NF-kappaB and induced IFN-beta in different porcine cell lines, but to varying degrees. Deletion mutant analysis revealed that both the DNA-binding domains and the C-terminus are required for full activation of IFN-beta. siRNA targeting poDAI significantly decreased poly(dAT:dAT)- or Pseudorabies virus (PRV)-induced IFN-beta activation. These results indicate that DAI is an important immuno-regulator of the porcine innate immune system.
Xie
Lilan
L
Division of Animal Infectious Diseases, State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China.
Fang
Liurong
L
Wang
Dang
D
Luo
Rui
R
Cai
Kaimei
K
Chen
Huanchun
H
Xiao
Shaobo
S
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002417:Cattle; D003001:Cloning, Molecular; D004285:Dogs; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D016899:Interferon-beta; D051379:Mice; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000276:immunology / Q000378:metabolism; D010802:Phylogeny; D034622:RNA Interference; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D015398:Signal Transduction / Q000276:immunology*; D013552:Swine; D014162:Transfection; D019892:eIF-2 Kinase / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*
D016328:NF-kappa B; D016899:Interferon-beta; D019892:eIF-2 Kinase