Integrative proteomics of primary hepatocytes during dedifferentiation

To understand the relationship between protein expression and mRNA translation during primary hepatocytes dedifferentiation, we have employed transcriptome microarrayas a discovery platform. Rat primary hepatocytes were isolated by the method of two-step enzymes perfusion and then cultured on mono-layer in vitro. Samples at 0h( just after perfusion, before planking) , 6h, 12h ,24h and 48h were collected. Integrative analysis of transcriptome and whole cell proteomics (WCP) leaded us to realize the poor correlation of them. This discovery made us realize that targeting mRNA was far from enough in illustrating this process. It would provide new insights from the aspects of post-translational modifications(PTMs).Post-translational modifications play important role in numorous biological and pathological process, but a few reports are related to primary hepatocytes dedifferentiation process, and there is still no integrative proteomics analysis in this field yet. In this study, we perform ubiquitinome phosphorylated proteome, whole cell proteome and transcriptome simultaneously during the five different time points of dedifferentiation in vitro quantified over 6000 modified sites mapping to over 2000 proteins. And comprehensive analysis of these datasets provides novel insight in this field. Dedifferentiation induced gene expression in primary rat hepatocytes was measured at 0, 6, 12, 24 and 48 hours after cultured in vitro monolayer. Three independent experiments were performed at each time point using different biological replicates.