Wed, 09/28/2016

A cell-type-resolved liver proteome, investigated by the National Center for Protein Science (Phoenix Center), is published online by Molecular & Cellular Proteomics, this study uses the new generation of high-dimensional proteomics technology to reveal the cellular constitution and division of labor of organs (liver) for the first time by analyzing the proteome of the major cell types of the liver.

Parenchymatous organs consist of multiple cell types, primarily defined as parenchymal cells (PCs) and non-parenchymal cells (NPCs). The cellular characteristics of these organs are not well understood. Proteomic studies facilitate the resolution of the molecular details of different cell types in organs. These studies have significantly extended our knowledge about organogenesis and organ cellular composition. Here, we present an atlas of the cell-type-resolved liver proteome. In-depth proteomics identified 6,000 to 8,000 gene products (GPs) for each cell type and a total of 10,075 GPs for four cell types. This dataset revealed features of the cellular composition of the liver: (1) hepatocytes (PCs) express the least GPs, have a unique but highly homogenous proteome pattern, and execute fundamental liver functions; (2) the division of labor among PCs and NPCs follows a model in which PCs make the downstream pathway components, but NPCs trigger the pathways; and (3) crosstalk among NPCs and PCs maintains the PC phenotype. This study presents the liver proteome at cell resolution, serving as a research model for dissecting the cell type constitution and organ features at the molecular level.