The Hedgehog (Hh) signaling pathway inhibits fat accumulation, which is conserved in a wide variety of organisms from Drosophila to vertebrates, but few reports about its effect on pigs are available. In this study, pig Gli1 gene was cloned for the first time by rapid amplification of cDNA ends (RACE) and RT-PCR. Pig Gli1 expression profiles were then studied in different tissues and in different developmental stages of the adipose tissue of pigs using real-time PCR. Finally, the eukaryotic expression vector and the adipose tissue specific expression vector were constructed. The results showed that the full pig Gli1 cDNA length was 3 576 bp, the genomic sequence contained 10 715 bp with 12 exons, and 1 106 amino acids were encoded. Pig Gli1 was predicted as an unstable hydrophilic protein without a tans-membrane structure or a signal peptide. The C2H2 zinc finger domain and a nuclear localization sequence were found in pig Gli1. A homology analysis of the Gli1 amino acids and the genomic sequences among seven species showed that the identities were all greater than 80%, which indicates that Gli1 is highly conserved among different species. Tissue expression profile analysis showed that pig Gli1 was only expressed in the tone tissue of adult pigs. Analysis of the pig adipose tissue developmental process showed that Gli1 was detected in the adipose tissue of one-week-old pigs, but not in one-month-old and three-month-old pigs. Finally, a pig Gli1 eukaryotic expression vector was constructed and properly expressed with cell transfection. An adipose tissue specific expression vector was constructed for transgenic animal studies.
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