Viral dew: Phase separation and the formation of viral replication compartments
Jens B. Bosse, Wolfram Brune
Abstract
Cellular life is based on compartmentalization to sequester biochemical reactions. Two kinds of cellular compartments exist: membrane-enclosed and membrane-less compartments. The cytoplasm of eukaryotic cells harbors many membrane-enclosed compartments, such as the endoplasmic reticulum, lysosomes, and peroxisomes. At the same time, the cytoplasm and especially the nucleus are compartmentalized by membrane-less structures, such as nucleoli, promyelocytic leukemia nuclear bodies (PML-NBs), nuclear speckles, and others. Not surprisingly, viruses hijack both compartment types to facilitate their replication. While the genesis of membrane-enclosed compartments has been studied for decades, research only recently focused on the biophysical properties of membrane-less compartments. Here, we outline the basic principles of their formation and how viruses generate such compartments for replication and morphogenesis. As excellent in-depth reviews have recently been published [1-3], this article is meant to serve as a brief introduction to the field.