Characterization of the porcine alpha interferon multigene family.
The availability of data on the pig genome sequence prompted us to characterize the porcine IFN-alpha (PoIFN-alpha) multigene family. Fourteen functional PoIFN-alpha genes and two PoIFN-alpha pseudogenes were detected in the porcine genome. Multiple sequence alignment revealed a C-terminal deletion of eight residues in six subtypes. A phylogenetic tree of the porcine IFN-alpha gene family defined the evolutionary relationship of the various subtypes. In addition, analysis of the evolutionary rate and the effect of positive selection suggested that the C-terminal deletion is a strategy for preservation in the genome. Eight PoIFN-alpha subtypes were isolated from the porcine liver genome and expressed in BHK-21 cells line. We detected the level of transcription by real-time quantitative RT-PCR analysis. The antiviral activities of the products were determined by WISH cells/Vesicular Stomatitis Virus (VSV) and PK 15 cells/Pseudorabies Virus (PRV) respectively. We found the antiviral activities of intact PoIFN-alpha genes are approximately 2-50 times higher than those of the subtypes with C-terminal deletions in WISH cells and 15-55 times higher in PK 15 cells. There was no obvious difference between the subtypes with and without C-terminal deletion on acid susceptibility.
Cheng
Gong
G
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, 220 Handan Road, Shanghai 200433, PR China.
Chen
Weizao
W
Li
Zuofeng
Z
Yan
Weiyao
W
Zhao
Xin
X
Xie
Jun
J
Liu
Mingqiu
M
Zhang
Hao
H
Zhong
Yang
Y
Zheng
Zhaoxin
Z
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D004247:DNA / Q000235:genetics; D004355:Drug Stability; D015870:Gene Expression; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016898:Interferon-alpha / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D011544:Pseudogenes; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D013552:Swine / Q000235:genetics* / Q000276:immunology*; D014780:Viruses / Q000276:immunology
D016898:Interferon-alpha; D004247:DNA