Molecular characterization and expression analysis of the IFN-gamma related gene (IFN-gammarel) in grass carp Ctenopharyngodon idella.
Interferon gamma (IFN-gamma), the only member of the type II class of interferons, has been identified in teleost fish. In addition to the IFN-gamma gene, fish possess an IFN-gamma related gene (IFN-gammarel) neighbouring the authentic IFN-gamma gene in the genome. In the present study, the cDNA sequence encoding 167 amino acids of IFN-gammarel and its genomic organization were identified in grass carp Ctenopharyngodon idella. The predicted protein sequence of grass carp IFN-gammarel (gcIFN-gammarel) showed 63% and 50% identities to zebrafish and common carp IFN-gammarel (previously termed as IFN-gamma1), respectively. The IFN-gammarel gene consists of 4 exons, with 3 intervening introns, spanning approximately 2kb of genomic sequence. The gcIFN-gammarel gene did not contain any polymorphic DNA repeats in the introns. Realtime PCR analysis showed that grass carp reovirus induced a high and long lasting (from days 1 to 7) expression of gcIFN-gammarel in spleen. The expression of gcIFN-gammarel in blood, head kidney, trunk kidney and spleen was also increased by bacterial peptidoglycan (PGN), lipopolysaccharide (LPS) and the interferon inducer polyI:C. The highest induction of gcIFN-gammarel expression by PGN was observed in spleen, then in blood and head kidney. Further analysis of the expression patterns of gcIFN-gammarel and PGN receptors, nucleotide oligomerization domains (NOD) 1 and 2, may suggest that IFN-gammarel was possibly activated in a NOD2-dependent mechanism.
Chen
W Q
WQ
College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei Province, PR China.
Xu
Q Q
QQ
Chang
M X
MX
Zou
J
J
Secombes
C J
CJ
Peng
K M
KM
Nie
P
P
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002347:Carps / Q000235:genetics* / Q000276:immunology* / Q000821:virology; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D005393:Fish Diseases / Q000235:genetics / Q000276:immunology; D029941:Fish Proteins / Q000235:genetics*; D015870:Gene Expression; D007371:Interferon-gamma / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012088:Reoviridae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013154:Spleen / Q000276:immunology
D017931:DNA Primers; D018076:DNA, Complementary; D029941:Fish Proteins; D007371:Interferon-gamma