Cargando…

Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis

Clathrin-mediated endocytosis is essential for the removal of transmembrane proteins from the plasma membrane in all eukaryotic cells. Many transmembrane proteins are glycosylated. These proteins collectively comprise the glycocalyx, a sugar-rich layer at the cell surface, which is responsible for i...

Descripción completa

Detalles Bibliográficos
Autores principales: Gollapudi, Sadhana, Jamal, Sabah, Kamatar, Advika, Yuan, Feng, Wang, Liping, Lafer, Eileen M., Belardi, Brian, Stachowiak, Jeanne C.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: National Academy of Sciences 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10104535/
https://www.ncbi.nlm.nih.gov/pubmed/37023126
http://dx.doi.org/10.1073/pnas.2215815120
_version_ 1785026059707613184
author Gollapudi, Sadhana
Jamal, Sabah
Kamatar, Advika
Yuan, Feng
Wang, Liping
Lafer, Eileen M.
Belardi, Brian
Stachowiak, Jeanne C.
author_facet Gollapudi, Sadhana
Jamal, Sabah
Kamatar, Advika
Yuan, Feng
Wang, Liping
Lafer, Eileen M.
Belardi, Brian
Stachowiak, Jeanne C.
author_sort Gollapudi, Sadhana
collection PubMed
description Clathrin-mediated endocytosis is essential for the removal of transmembrane proteins from the plasma membrane in all eukaryotic cells. Many transmembrane proteins are glycosylated. These proteins collectively comprise the glycocalyx, a sugar-rich layer at the cell surface, which is responsible for intercellular adhesion and recognition. Previous work has suggested that glycosylation of transmembrane proteins reduces their removal from the plasma membrane by endocytosis. However, the mechanism responsible for this effect remains unknown. To study the impact of glycosylation on endocytosis, we replaced the ectodomain of the transferrin receptor, a well-studied transmembrane protein that undergoes clathrin-mediated endocytosis, with the ectodomain of MUC1, which is highly glycosylated. When we expressed this transmembrane fusion protein in mammalian epithelial cells, we found that its recruitment to endocytic structures was substantially reduced in comparison to a version of the protein that lacked the MUC1 ectodomain. This reduction could not be explained by a loss of mobility on the cell surface or changes in endocytic dynamics. Instead, we found that the bulky MUC1 ectodomain presented a steric barrier to endocytosis. Specifically, the peptide backbone of the ectodomain and its glycosylation each made steric contributions, which drove comparable reductions in endocytosis. These results suggest that glycosylation constitutes a biophysical signal for retention of transmembrane proteins at the plasma membrane. This mechanism could be modulated in multiple disease states that exploit the glycocalyx, from cancer to atherosclerosis.
format Online
Article
Text
id pubmed-10104535
institution National Center for Biotechnology Information
language English
publishDate 2023
publisher National Academy of Sciences
record_format MEDLINE/PubMed
spelling pubmed-101045352023-10-06 Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis Gollapudi, Sadhana Jamal, Sabah Kamatar, Advika Yuan, Feng Wang, Liping Lafer, Eileen M. Belardi, Brian Stachowiak, Jeanne C. Proc Natl Acad Sci U S A Biological Sciences Clathrin-mediated endocytosis is essential for the removal of transmembrane proteins from the plasma membrane in all eukaryotic cells. Many transmembrane proteins are glycosylated. These proteins collectively comprise the glycocalyx, a sugar-rich layer at the cell surface, which is responsible for intercellular adhesion and recognition. Previous work has suggested that glycosylation of transmembrane proteins reduces their removal from the plasma membrane by endocytosis. However, the mechanism responsible for this effect remains unknown. To study the impact of glycosylation on endocytosis, we replaced the ectodomain of the transferrin receptor, a well-studied transmembrane protein that undergoes clathrin-mediated endocytosis, with the ectodomain of MUC1, which is highly glycosylated. When we expressed this transmembrane fusion protein in mammalian epithelial cells, we found that its recruitment to endocytic structures was substantially reduced in comparison to a version of the protein that lacked the MUC1 ectodomain. This reduction could not be explained by a loss of mobility on the cell surface or changes in endocytic dynamics. Instead, we found that the bulky MUC1 ectodomain presented a steric barrier to endocytosis. Specifically, the peptide backbone of the ectodomain and its glycosylation each made steric contributions, which drove comparable reductions in endocytosis. These results suggest that glycosylation constitutes a biophysical signal for retention of transmembrane proteins at the plasma membrane. This mechanism could be modulated in multiple disease states that exploit the glycocalyx, from cancer to atherosclerosis. National Academy of Sciences 2023-04-06 2023-04-11 /pmc/articles/PMC10104535/ /pubmed/37023126 http://dx.doi.org/10.1073/pnas.2215815120 Text en Copyright © 2023 the Author(s). Published by PNAS. https://creativecommons.org/licenses/by-nc-nd/4.0/This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND) (https://creativecommons.org/licenses/by-nc-nd/4.0/) .
spellingShingle Biological Sciences
Gollapudi, Sadhana
Jamal, Sabah
Kamatar, Advika
Yuan, Feng
Wang, Liping
Lafer, Eileen M.
Belardi, Brian
Stachowiak, Jeanne C.
Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
title Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
title_full Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
title_fullStr Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
title_full_unstemmed Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
title_short Steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
title_sort steric pressure between glycosylated transmembrane proteins inhibits internalization by endocytosis
topic Biological Sciences
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10104535/
https://www.ncbi.nlm.nih.gov/pubmed/37023126
http://dx.doi.org/10.1073/pnas.2215815120
work_keys_str_mv AT gollapudisadhana stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT jamalsabah stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT kamataradvika stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT yuanfeng stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT wangliping stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT lafereileenm stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT belardibrian stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis
AT stachowiakjeannec stericpressurebetweenglycosylatedtransmembraneproteinsinhibitsinternalizationbyendocytosis