ESCPE-1 mediates retrograde endosomal sorting of the SARS-CoV-2 host factor Neuropilin-1

Abstract

Endosomal sorting maintains cellular homeostasis by recycling transmembrane proteins and associated proteins and lipids (termed “cargoes”) from the endosomal network to multiple subcellular destinations, including retrograde traffic to the trans -Golgi network (TGN). Viral and bacterial pathogens subvert retrograde trafficking machinery to facilitate infectivity. Here, we develop a proteomic screen to identify retrograde cargo proteins of the endosomal SNX-BAR sorting complex promoting exit 1 (ESCPE-1). Using this methodology, we identify Neuropilin-1 (NRP1), a recently characterized host factor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, as a cargo directly bound and trafficked by ESCPE-1. ESCPE-1 mediates retrograde trafficking of engineered nanoparticles functionalized with the NRP1-interacting peptide of the SARS-CoV-2 spike (S) protein. CRISPR-Cas9 deletion of ESCPE-1 subunits reduces SARS-CoV-2 infection levels in cell culture. ESCPE-1 sorting of NRP1 may therefore play a role in the intracellular membrane trafficking of NRP1-interacting viruses such as SARS-CoV-2.

Effect of Conformational Variability on Seasonable Thermal Stability and Cell Entry of Omicron Variants

“…Even though the cell entry through the endocytic pathway, the S1/S2 separation is a prerequisite for membrane fusion. Neuropilin-1 (NRP1) is another host factor that facilitates SARS-CoV-2 infection , and has been identified as a direct cargo sorted by the endosomal SNX-BAR sorting complex promoting exit 1 (ESCPE-1) for the endosomal sorting related to the retrograde transport from endosomes to the trans-Golgi network . NRP1 interacts with the C-end rule (CendR) peptide motif at the furin cleavage site (residues 682–685), but unfortunately, the cryo-EM structures of CendR for Omicron variants remain elusive (Figure ).…”

CHC22 clathrin functions in the early secretory pathway by two-site interaction with SNX5 and p115

“…The requirement of SNX5/6 for CHC22 localization raises the question of whether known partners of SNX5/6 are also involved. To address this, CHC22 localization was tested in HeLa cells lacking SNX1/2, which dimerize with SNX5/6 in the endosomal ESCPE-1 complex (Simonetti et al, 2022; Simonetti et al, 2017; Simonetti et al, 2019), with further examination of whether CHC22 localization is affected in cells lacking the human VPS26A/B:VPS35:VPS29 Retromer complex. The retromer-null ( ΔVPS35 ) and SNX1/2-null cells ( ΔSNX1/2 ) were produced by CRISPR engineering and characterized in earlier studies (Simonetti et al, 2022; Simonetti et al, 2017; Simonetti et al, 2019).…”

“…These SNX-BAR protein family members were initially implicated in Retromer sorting at endosomes by homology with yeast proteins (Rojas et al, 2007; Simonetti and Cullen, 2018; van Weering et al, 2012; Wassmer et al, 2007). However, it is now established that SNX5/6 heterodimerize with SNX1, or its functionally-redundant paralogue protein SNX2, to form the ESCPE-1 complex, which is distinct from conventional Retromer and mediates separate endosomal sorting pathways (Evans et al, 2020; Simonetti et al, 2022; Simonetti et al, 2019). The resulting SNX-BAR ESCPE-1 heterodimers interact with lipids through the PX domain of SNX1/2 and with cargo through the PX of SNX5/6 (Evans et al, 2020; Kvainickas et al, 2017; Simonetti et al, 2017; van Weering et al, 2012).…”

Cerebral microvascular complications associated with SARS-CoV-2 infection: How did it occur and how should it be treated?

“…The results of an in vivo study illustrate a critical role for the furin cleavage site in COVID-19 infection and report that in the absence of this site, the replication of SARS-CoV-2 can be attenuated [79] . In addition, recently, it has been suggested that neuropilin-1 (NRP1) is another cofactor, which can facilitate the interaction of SARS-CoV-2 spike protein S1 subunit with ACE2 and promote infection into cells [80] , [81] , [82] . However, despite the presence of proteases to regulate the process of membrane fusion, the virus usually prefers to enter the cell through endocytosis [77] .…”