Journal Article

A New Role for Clathrin Adaptor Proteins 1 and 3 in Lipoplex Trafficking

Gumbs, Jade, Alford, Justine E., Anderson, Emma C.

2014

Overview

Intracellular protein trafficking through secretory and endocytic pathways depends on the function of adaptor proteins that bind motifs on cargo proteins. The adaptor proteins then recruit coat proteins such as clathrin, enabling the formation of a transport vesicle. While studying the role of the clathrin adaptor proteins, AP-1, AP-2 and AP-3 in viral protein trafficking, we discovered that AP-1 and AP-3 potentially have a role in successful transfection of mammalian cells with DNA-liposome complexes (lipoplexes). We showed that AP-1, -2 and -3 are not required for lipoplexes to enter cells, but that lipoplexes and/or released DNA are unable to reach the nucleus in the absence of AP-1 or AP-3, leading to minimal exogenous gene expression. In contrast, gene expression from liposome-delivered mRNA, which does not require nuclear entry, was not impaired by the absence of AP-1 or AP-3. Despite the use of lipoplexes to mediate gene delivery being so widely used in cell biology and, more recently, gene therapy, the mechanism by which lipoplexes or DNA reach the nucleus is poorly characterised. This work sheds light on the components involved in this process, and demonstrates a novel role for AP-1 and AP-3 in trafficking lipoplexes.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adaptor Protein Complex 1 - genetics / Adaptor Protein Complex 1 - metabolism / Adaptor Protein Complex 3 - genetics / Adaptor Protein Complex 3 - metabolism / Adaptor proteins / Biological Transport / Biology / Cell Line / Cell Nucleus - metabolism / Cells (Biology) / Clathrin / Deoxyribonucleic acid / DNA / DNA - metabolism / Endocytosis / gag Gene Products, Human Immunodeficiency Virus - genetics / gag Gene Products, Human Immunodeficiency Virus - metabolism / Gene Expression / Gene Knockdown Techniques / Gene therapy / Gene transfer / HIV / Hostages / Human immunodeficiency virus / Humans / Infection / Intracellular Space - metabolism / Life sciences / Liposomes - metabolism / Mammalian cells / Microscopy / Nuclei / Plasmids / Plasmids - genetics / Protein binding / Protein transport / Proteins / RNA / RNA Interference / Transcription factors / Transfection / Viral proteins