Article

Inductive expression and characterization analysis of Paralichthys olivaceus pigment epithelium-derived factor in a virally infected cell line.

State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Wuhan 430072, China.
Biochemical and Biophysical Research Communications (impact factor: 2.48). 10/2005; 335(3):799-809. DOI:10.1016/j.bbrc.2005.07.143 pp.799-809
Source: PubMed

ABSTRACT Pigment epithelium-derived factor (PEDF) is acknowledged to be a non-inhibitory member of the serine protease inhibitor (serpin) superfamily, with antiangiogenesis, and neuroprotective and immunoregulatory function, mainly in the tissues of nervous system. Here, A PEDF gene homolog, Paralichthys olivaceus PEDF (PoPEDF), was isolated from flounder embryonic cells (FEC) treated with UV-inactivated Grass carp hemorrhage virus (GCHV) and subsequently identified as a differentially expressed gene. The full length of PoPEDF cDNA is 1803bp with an open reading frame of 1212bp encoding a 403-amino-acid protein. This deduced protein contains an N-terminal signal peptide, a glycosylation site, a consensus serpin motif, and a 34-mer and a 44-mer fragment, all of which are very conserved in the PEDF family. PoPEDF gene exhibits a conserved exon-intron arrangement with 8 exons and 7 introns. This conserved evolutionary relationship was further confirmed by a phylogenetic analysis, where fish PEDFs and mammalian members formed a well-supported clade. Constitutive expression of PoPEDF was widely detected in many tissues. In response to UV-inactivated GCHV or poly(I:C), PEDF mRNA was upregulated in FEC cells with time. This is the first report on the transcriptional induction of PEDF in virally infected cells.

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Keywords

403-amino-acid protein
 
44-mer fragment
 
8 exons
 
consensus serpin motif
 
conserved evolutionary relationship
 
conserved exon-intron arrangement
 
deduced protein
 
fish PEDFs
 
flounder embryonic cells
 
glycosylation site
 
immunoregulatory function
 
mammalian members
 
N-terminal signal peptide
 
open reading frame
 
Paralichthys olivaceus PEDF
 
PEDF gene homolog
 
phylogenetic analysis
 
Pigment epithelium-derived factor
 
PoPEDF cDNA
 
serine protease inhibitor