The Golgi sorting domain of coronavirus E1 protein

The coronavirus E1 membrane protein is confined to the Golgi after it is expressed in cells either by viral infection or via injection of synthetic RNA. We have investigated the features of the protein responsible for intracellular sorting and found that a C-terminal deletion of only 18 amino acids results in its transport to the plasma membrane. However, we have previously shown that this C-terminal region alone is not sufficient for Golgi retention. When E1 was fused to a cell-surface protein, Thy-1, the resulting molecule was retained in the Golgi. Various mutated forms of E1 whose destinations were the ER, cell surface or lysosomes were also fused to Thy-1, and in each case the fusion was sorted according to its E1 component alone. We argue that, in contrast to sorting signals for other membrane compartments, Golgi retention of E1 is not due to a single short peptide sequence. Instead, the Golgi ‘signal’ of E1 appears to require for its expression a domain comprising most of the sequence of the protein.

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Leukocytes with chromosome Y loss have reduced abundance of the cell surface immunoprotein CD99

Scientific Reports ◽

10.1038/s41598-021-94588-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jonas Mattisson ◽

Marcus Danielsson ◽

Maria Hammond ◽

Hanna Davies ◽

Caroline J. Gallant ◽

...

Keyword(s):

Cell Surface ◽

Single Cells ◽

Surface Protein ◽

Protein Abundance ◽

Blood Leukocytes ◽

Chromosome Y ◽

Increased Risk ◽

A Cell ◽

Pseudoautosomal Regions ◽

Male Specific

AbstractMosaic loss of chromosome Y (LOY) in immune cells is a male-specific mutation associated with increased risk for morbidity and mortality. The CD99 gene, positioned in the pseudoautosomal regions of chromosomes X and Y, encodes a cell surface protein essential for several key properties of leukocytes and immune system functions. Here we used CITE-seq for simultaneous quantification of CD99 derived mRNA and cell surface CD99 protein abundance in relation to LOY in single cells. The abundance of CD99 molecules was lower on the surfaces of LOY cells compared with cells without this aneuploidy in all six types of leukocytes studied, while the abundance of CD proteins encoded by genes located on autosomal chromosomes were independent from LOY. These results connect LOY in single cells with immune related cellular properties at the protein level, providing mechanistic insight regarding disease vulnerability in men affected with mosaic chromosome Y loss in blood leukocytes.

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Localization and expression of msp130, a primary mesenchyme lineage-specific cell surface protein in the sea urchin embryo

Development ◽

10.1242/dev.101.2.255 ◽

1987 ◽

Vol 101 (2) ◽

pp. 255-265 ◽

Cited By ~ 4

Author(s):

J.A. Anstrom ◽

J.E. Chin ◽

D.S. Leaf ◽

A.L. Parks ◽

R.A. Raff

Keyword(s):

Cell Surface ◽

Sea Urchin ◽

Sea Water ◽

Surface Protein ◽

Specific Cell ◽

Cell Surface Protein ◽

Sea Urchin Embryo ◽

A Cell ◽

Mesenchyme Cells ◽

Primary Mesenchyme Cells

In this report, we use a monoclonal antibody (B2C2) and antibodies against a fusion protein (Leaf et al. 1987) to characterize msp130, a cell surface protein specific to the primary mesenchyme cells of the sea urchin embryo. This protein first appears on the surface of these cells upon ingression into the blastocoel. Immunoelectronmicroscopy shows that msp130 is present in the trans side of the Golgi apparatus and on the extracellular surface of primary mesenchyme cells. Four precursor proteins to msp130 are identified and we show that B2C2 recognizes only the mature form of msp130. We demonstrate that msp130 contains N-linked carbohydrate groups and that the B2C2 epitope is sensitive to endoglycosidase F digestion. Evidence that msp130 is apparently a sulphated glycoprotein is presented. The recognition of the B2C2 epitope of msp130 is disrupted when embryos are cultured in sulphate-free sea water. In addition, two-dimensional immunoblots show that msp130 is an acidic protein that becomes substantially less acidic in the absence of sulphate. We also show that two other independently derived monoclonal antibodies, IG8 (McClay et al. 1983; McClay, Matranga & Wessel, 1985) and 1223 (Carson et al. 1985), recognize msp130, and suggest this protein to be a major cell surface antigen of primary mesenchyme cells.

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A cell surface protein controls endocrine ring gland morphogenesis and steroid production

Developmental Biology ◽

10.1016/j.ydbio.2018.10.007 ◽

2019 ◽

Vol 445 (1) ◽

pp. 16-28 ◽

Cited By ~ 2

Author(s):

Yanina-Yasmin Pesch ◽

Ricarda Hesse ◽

Tariq Ali ◽

Matthias Behr

Keyword(s):

Cell Surface ◽

Surface Protein ◽

Cell Surface Protein ◽

Steroid Production ◽

Ring Gland ◽

A Cell ◽

Gland Morphogenesis

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The in silico human surfaceome

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1808790115 ◽

2018 ◽

Vol 115 (46) ◽

pp. E10988-E10997 ◽

Cited By ~ 44

Author(s):

Damaris Bausch-Fluck ◽

Ulrich Goldmann ◽

Sebastian Müller ◽

Marc van Oostrum ◽

Maik Müller ◽

...

Keyword(s):

Cell Surface ◽

In Silico ◽

Embryonic Stem ◽

Surface Protein ◽

Surface Proteins ◽

Cell Surface Protein ◽

Cell Surface Proteins ◽

A Cell ◽

Visualization Tools ◽

Protein Classes

Cell-surface proteins are of great biomedical importance, as demonstrated by the fact that 66% of approved human drugs listed in the DrugBank database target a cell-surface protein. Despite this biomedical relevance, there has been no comprehensive assessment of the human surfaceome, and only a fraction of the predicted 5,000 human transmembrane proteins have been shown to be located at the plasma membrane. To enable analysis of the human surfaceome, we developed the surfaceome predictor SURFY, based on machine learning. As a training set, we used experimentally verified high-confidence cell-surface proteins from the Cell Surface Protein Atlas (CSPA) and trained a random forest classifier on 131 features per protein and, specifically, per topological domain. SURFY was used to predict a human surfaceome of 2,886 proteins with an accuracy of 93.5%, which shows excellent overlap with known cell-surface protein classes (i.e., receptors). In deposited mRNA data, we found that between 543 and 1,100 surfaceome genes were expressed in cancer cell lines and maximally 1,700 surfaceome genes were expressed in embryonic stem cells and derivative lines. Thus, the surfaceome diversity depends on cell type and appears to be more dynamic than the nonsurface proteome. To make the predicted surfaceome readily accessible to the research community, we provide visualization tools for intuitive interrogation (wlab.ethz.ch/surfaceome). The in silico surfaceome enables the filtering of data generated by multiomics screens and supports the elucidation of the surfaceome nanoscale organization.

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