Studies On Differential Expression From In Different Diets Of Energy Levels And Alternative Splicing Forms Of Lipin1 MRNA In Chicken

Lipin1 gene play an important role in the body. Lipin1 gene may encode Mg2+-dependent phosphatidate (PA) phosphatase. Studies demonstrate that modulation of Lipin1 gene expression may lead to strongly effects on adipose deposition in human and mouse, but the opposite conclusion we have noted between Lipin1 transgenic over expression mouse and normal human。So there will be very necessary to furtherly investigate effects on adipose deposition of Lipin1 gene in other natural model animal population. Analysis of comparative genomics shows that Lipin1 gene also may be a potentially candidate gene for fat deposition in chicken. In the present study, the cDNA sequence of the chicken Lipin1 gene had been obtained by RT-PCR, and sequence polymorphism had been analyzed. Thus we carried out correlated investigation about differential expression of chicken Lipin1 gene in this experiment.This study is divided into two parts:Experiment 1: Studies on differential expression from in different tissues and alternative splicing forms of Lipin1 mRNA in chicken(1),Studies on screening the best primers for differential expression of chicken Lipin1 gene and amplification products tissue specificityIn the course of screening the best primers for differential expression of chicken Lipin1 gene, through the RT- PCR method, we obtained two alternative splicing forms of chicken Lipin1 gene: chicken Lipin1-βand chicken Lipin1-γ. Because the introns retention in the course of chicken Lipin1 gene transcription. Chicken Lipin1-βencoding a protein of 937 amino acids, and chicken Lipin1-γencoding a protein of 918 amino acids. Chicken Lipin1-βmRNA had a high level of expression in the heart and pectoralis, but it was not expressed in other tissues examined. Chicken Lipin1-γmRNA had a high level of expression in the lung, spleen, fat, heart, liver and cartilaginous tissue, a low level of expression in the pectoralis and brain tissue, a lowest level of expression in the pancreas. In this experiment, we obtained the best primers for differential expression of chicken Lipin1 gene.(2),Through the semi-quantitative PCR to determine the differential expression of chicken Lipin1 gene in different tissuesRT-PCR analysis showed that the chicken Lipin1 gene was expressed in almost all tissues examined. Chicken Lipin1 mRNA had a high level of expression in the lung, spleen, fat, heart, pectoralis, brain and liver tissue, a low level of expression in the pancreas and cartilaginous tissue.Experiment 2: Through the quantitative PCR to determine the differential expression of chicken Lipin1 gene in different diets of energy levels in Arbor Acres broiler energy restriction expression groupQuantitative PCR analysis showed that expression of chicken Lipin1 gene mRNA in fat tissue was increased 3.8-fold in energy restriction group birds compared with free feeding group birds (p<0.05); and expression of chicken Lipin1 gene mRNA in liver tissue was increased 4.4-fold in energy restriction group birds compared with free feeding group birds (p<0.01) respectively.Studies on the relationship between phenotypic and physiological and biochemical indicators with Lipin1 gene expression in liver tissues. The analysis results showed that there was a significantly inverse correlation between chicken Lipin1 gene mRNA expression level and ratio of feed to body weight gain, abdomen fat weight(p<0.05), there was a extremely significantly inverse correlation between chicken Lipin1 gene mRNA expression level and abdomen fat rate(p<0.01); whereas no significantly correlation was observed between chicken Lipin1 gene mRNA expression level and body weight, average day gain, thickness of subcutaneous fat(p>0.05). There was a significantly inverse correlation between chicken Lipin1 gene mRNA expression level and high density lipoprotein(HDL-C), alkaline phosphatase(AKP)(p<0.05), there was a extremely significantly inverse correlation between chicken Lipin1 gene mRNA expression level and total cholesterol(p<0.01), there was a extremely significantlypositive correlation between chicken Lipin1 gene mRNA expression level and total cholesterol(p<0.01); whereas no significantly correlation was observed between chicken Lipin1 gene mRNA expression level and glucose(GLU), triglyceride(TG), blood urea nitrogen(BUN), lactic acid dehydrogenase(LDH), CHO/HDL, CHO-HDL, insulin(INS)(p>0.05).This experiment lay the foundation for studying the role and interpreting the molecule mechanism of adipose deposition of the Chicken Lipin1gene.