Gene Microarray Analysis for Porcine Adipose Tissue: Comparison of Gene Expression between Chinese Xiang Pig and Large White

W Guo,J Zhang,C H Wu,K Xu,N Li,H J Cao,S H Wang,L Zhang,W Lu,J D Feng,Z L Du

doi:10.5713/ajas.2008.60256

Abstract

We created a cDNA microarray representing approximately 3,500 pig genes for functional genomic studies. The array elements were selected from 6,494 cDNA clones identified in a large-scale expressed sequence tag (EST) project. These cDNA clones came from normalized and subtracted porcine adipose tissue cDNA libraries. Sequence similarity searches of the 3,426 ESTs represented on the array using BLASTN identified 2,790 (81.4%) as putative human orthologs, with the remainder consisting of novel genes or highly divergent orthologs. We used the gene microarray to profile transcripts expressed by adipose tissue of fatty Chinese Xiang pig (XP) and muscley Large White (LW). Microarray analysis of RNA extracted from adipose tissue of fatty XP and muscley LW identified 81 genes that were differently expressed two fold or more. Transcriptional differences of four of these genes, adipocyte fatty acid binding protein (aP2), stearyl-CoA desaturase (SCD), sterol regulatory element binding transcription factor 1 (SREBF1) and lipoprotein lipase (LPL) were confirmed using SYBR Green quantitative RT-PCR technology. Our results showed that high expression of SCD and SREBF1 may be one of the reasons that larger fat deposits are observed in the XP. In addition, our findings also illustrate the potential power of microarrays for understanding the molecular mechanisms of porcine development, disease resistance, nutrition, fertility and production traits.

Highlights

Gene expression microarrays are a powerful and flexible new tool in molecular biology (Brown and Botstein., 1999) and permit the simultaneous measurement of transcription levels of thousands of genes in different physiological states of an organism tissue or cell (Schena et al, 1996; Shalon et al, 1996)
Because Large White (LW) known as Yorkshire is a breed from north of England and is referred as representative muscly pig, Chinese Xiang pig (XP) is referred as fatty big and deposited more fat than LW, we profiled transcription difference between adipose tissues of fatty Chinese XP and muscly LW by the cDNA microarray
expressed sequence tag (EST) clustering and annotation From among 6,494 high quality sequences obtained from normalized porcine adipose tissues cDNA libraries, Guo et al (2008) Asian-Aust

Summary

Introduction

Gene expression microarrays are a powerful and flexible new tool in molecular biology (Brown and Botstein., 1999) and permit the simultaneous measurement of transcription levels of thousands of genes in different physiological states of an organism tissue or cell (Schena et al, 1996; Shalon et al, 1996). For each pair of samples, each gene was represented triplicate on each slide, and the experiments were performed in duplicate by dye swap, producing 6 data points, so that we determined the differently expressed genes based on the statistical program student t-test.

Results

Conclusion