Cloning and tissue expression analysis of CIDEc gene in Longlin goat

【Objective】To investigate the biological characteristics and expression pattern of DFF45-like effector C gene(CIDEc) in Longlin goat, and to provide theoretical basis for revealing the regulation mechanism of CIDEc gene on goat fat.【Method】Total RNA was extracted from longissimus dorsi muscle, heart, liver, spleen, kidney, abdominal fat and subcutaneous fat of Longlin goat, and abdominal fat and subcutaneous fat of Nubia goat. The sequence of CIDEc gene coding region(CDS) of Longlin goats was amplified by PCR. Online softwares such as ExPASy, TMHMM Server v. 2.0, ProtScale, NPS@SOPMA and SSWISS-Model were used for bioinformatics analysis, and real-time fluorescence quantitative PCR was used to detect the expression of CIDEc gene in different tissues and organs of Longlin goat and Nubia goat.【Result】The CDS sequence of Longlin goat CIDEc gene was 741 bp, encoding 244 amino acid residues. The molecular weight of the encoded protein was 26.09 kD, the instability coefficient was 48.44, the fat index was 100.7, and the theoretical isoelectric point(pI) was 5.28. It was an acidic protein with no transmembrane structure and strong hydrophilicity. The CDS sequence of Longlin goat CIDEc gene had only one mutation compared with the CDS sequence of common goat CIDEc gene(XM_018038444.6) published by NCBI, that was, the mutation at site 560 G was changed to T, which belonged to the synonym mutation. The CDS sequence of CIDEc gene of Longlin goat was the highest in similarity with that of sheep(99.0%), and the lowest in similarity with that of mice(79.6%). The phylogenetic tree constructed based on the similarity of CIDEc gene CDS sequence also showed that Longlin goat was the most closely related to sheep, and closely related to mice. In the secondary structure of Longlin goat CIDEc protein, there were 32.38% of equenxes, 12.70% of quturns, 13.11% of extended chains and 41.80% of irregular coils. The CIDEc gene was expressed in all 7 tissues and organs of Longlin goats, and the CIDEc gene was highly expressed in abdominal fat and subcutaneous fat, which was extremely significantly higher than that in other organs and tissues(P<0.01). The relative expression level of CIDEc gene in adipose tissue(subcutaneous adipose tissue and abdominal adipose tissue) of Nubia goat was significantly higher than that of Longlin goat(P<0.05). 【Conclusion】CIDEc gene is expressed in all organs and tissues of Longlin goat, especially in adipose tissue, and its expression level in adipose tissue(subcutaneous fat and abdominal fat) of Nubian goat is significantly higher than that in Longlin goat. CIDEc protein is an important regulator of fat metabolism and is closely related to lipid storage in animals.