Abstract:

This experiment was conducted to clone and identify the spliced variants of the TLR4 gene, and analyze the regulation of their gene expression in duck. Based on the sequence of TLR4 gene in GenBank(accession number:JN048668)，the primers were designed，and the TLR4 gene was obtained by the RT-PCR. The temporal and spatial expression pattern was detected by qRT-PCR to analysis the levels of transcript variants in different tissues by constructing the polyI:C infection duck model. One new transcript variants(TLR4-b) of duck TLR4 gene was found, and sequences analysis showed that it was an alternative exon between the first and the second exon. The tissue expression analysis showed that the expression of TLR4 was mainly wild type(TLR4-a). And the expression of TLR4-a mRNA always increased firstly, then decreased in lung and spleen after the stimulation of ployI:C, but the expression of TLR4-b had little change. The new splicing isoforms(TLR4-b) of TLR4 gene was cloned and identified sucessfully in duck. The expression of TLR4-a was higher than that of TLR4-b under normal conditions, but the expression level of TLR4-a gene firstly increased, then decreased after ployI:C stimulation. The results preliminary reveal the structure of TLR4 gene transcript variant in duck, and its function mainly depends on TLR4-a gene.