Cytokinesis, as the last stage of the cell division cycle, is a tightly controlled process amongst all eukaryotes, and defective division can lead to severe cellular consequences, and is implicated in serious human diseases and conditions such as cancer. Both mammalian cells and the fission yeast Schizosaccharomyces pombe use binary fission to divide into two equal sized daughter cells. Similar to mammalian cells, in S. pombe such cytokinetic division is driven by the assembly of an actin-myosin contractile ring (ACR) at the cell equator between the two cell tips. The ACR is composed of a complex network of membrane scaffold proteins, actin filaments, myosin motors, and other cytokinesis regulators. Contraction of the ACR leads to the formation of a cleavage furrow which is severed by the endosomal sorting complex required for transport (ESCRT) proteins leading to the final cell separation during the last stage of cytokinesis, abscission. This review describes recent findings defining the three phases to establish cytokinesis in S. pombe: ACR assembly, ACR constriction, and its coordination with septation. Collectively, we provide an overview of current understanding of the mechanisms regulating the ACR-mediated cytokinesis in S. pombe with a potential role of ESCRT proteins in this process.

The endosomal sorting complex required for transport (ESCRT) is an essential molecular machinery in eukaryotic cells that facilitates the invagination of endosomal membranes, leading to the formation of multivesicular bodies (MVBs). It participates in various cellular processes, including lipid bilayer remodeling, cytoplasmic separation, autophagy, membrane fission and remodeling, plasma membrane repair, as well as the invasion, budding, and release of certain enveloped viruses. The ESCRT complex consists of five complexes, ESCRT-0 to ESCRT-III and VPS4, along with several accessory proteins. ESCRT-0 to ESCRT-II form soluble complexes that shuttle between the cytoplasm and membranes, mainly responsible for recruiting and transporting membrane proteins and viral particles, as well as recruiting ESCRT-III for membrane neck scission. ESCRT-III, a soluble monomer, directly participates in vesicle scission and release, while VPS4 hydrolyzes ATP to provide energy for ESCRT-III complex disassembly, enabling recycling. Studies have confirmed the hijacking of ESCRT complexes by enveloped viruses to facilitate their entry, replication, and budding. Recent research has focused on the interaction between various components of the ESCRT complex and different viruses. In this review, we discuss how different viruses hijack specific ESCRT regulatory proteins to impact the viral life cycle, aiming to explore commonalities in the interaction between viruses and the ESCRT system.

Although phylogenetic analysis shows coronaviruses (CoV) share similar genome sequences, CoVs encode different number of proteins (5 to 14). The newly isolated viruses harbour more proteins than the old ones. Therefore, identifying the functional protein unites will benefits to understand the molecular interactions of the virus, and then identify molecular targets for antiviral drug. Here, the comparative in-silico analysis of 33 coronavirus proteomes show that coronaviruses harbour diverse number of protein functional motifs. Coronaviruses harbour wide-range of motifs including those involved in integrin-binding and ESCRT pathway before virus budding. For example, SARS-CoV-2, but not SARS-CoV-1, encodes PPxY motif, which is required for virus entry and budding of HIV, influenza and adenoviruses. The quinolone inulding the antiviral FGI-104 is able to block ESCRT pathway and viral budding and has been used against HIV, HCV and Ebola virus.