Differentially expressed genes analysis by cDNA microarray during liver regenration after partial hepatectomy and different stages of liver development in rats.. Rattus norvegicus

Liver transcriptome codes for diverse metabolic functions and involves several pathways. During different developmental stage of rat liver, differential expression of specific genes occur and allow the liver cells to enter into the further developmental stage. In regenerating rat liver, the mass of the lost liver is regained by a highly synchronized multi-step process involving expression of specific genes in a temporal manner. In our study, the transcriptional profile of developing liver (2wks and 4 wks), regenerating liver and adult liver based on microarray data has been systematically compared. Also the biological relevance of differentially expressed genes were also analysed through gene ontology (GO) and pathway analysis. Overall design: Rat liver was excised out from the animals of different age groups (2 weeks, 4 weeks and 12 weeks) and partially hepatectomized rats at 8 h post surgery, for RNA extraction and hybridization on affymetrix microarray. Each sample was processed in duplicate and checked for quality of total RNA. The RNA was used as a starting template to synthesize double-stranded cDNA with random hexamers tagged with T7 promoter sequence. The fragmented DNA was labeled and used for overnight hybridization with Rat Gene ST 1.0 arrays, followed by washing, staining and scanning.