Subcellular Proteomics Today

Abstract

Subcellular proteomics is concerned with the study of organelles, their protein components and their dynamics. By identifying the resident proteins, we are better able to understand the structural organization and function of a specific organelle. Traditionally the study of subcellular structures began with the isolation of organelles and the subsequent biochemical characterization of their components. Recently, localization of individual proteins on a proteome-wide scale has been studied using microscopy, employing either antibodies or fluorescently tagged proteins. However, it is the advent and application of high throughput mass spectrometry-based proteomics that have made system-wide organelle studies a reality. Nevertheless, one of the main challenges in this field is to fully characterize all subcellular proteomes, and to understand the dynamic changes in protein localization in response to various perturbations. In this Special Issue of Proteomics, we have put together a collection of 12 review articles and 3 original research papers in the area of subcellular proteomics. It aims to provide an update on recent approaches adopted to characterize organelle proteomes, and to summarize the results on the structure and function of several of the organelles that have been studied. Accordingly, the articles in this Special Issue are organized into two broad categories. The first category contains contributions that are mainly concerned with methodologies used in organellar proteomics. It includes review articles on subcellular fractionation methods and strategies, the experimental design and analysis of organelle proteomics, prediction of subcellular locations of proteins and the creation of an antibody-based subcellular protein atlas. As for the second category of contributions, the proteomes of several organelles (including the functional aspects of the protein components present within), viz., plasma membrane, mitochondria, clathrin-coated vesicles, endoplasmic reticulum, lysosomes, nucleolus, phagosome, endosome, and spliceosome are presented and discussed. Lastly a research article that summarizes the results on the membrane protein initiative (MPI) of the Asian Oceanian Human Proteome Organization (AOHUPO) is also included in this Special Issue. We hope that our readers will find the articles in this issue to be interesting and useful, especially for those who are about to embark on this interesting area of research. On a final note, I wish to thank all the authors for their excellent contributions that have made this issue possible. Their cooperation and efforts to meet the publication deadline are also greatly appreciated. Maxey Chung