CALM supports clathrin-coated vesicle completion upon membrane tension increase.

Abstract

The most represented components of clathrin-coated vesicles (CCVs) are clathrin triskelia and the adaptors clathrin assembly lymphoid myeloid leukemia protein (CALM) and the heterotetrameric complex AP2. Investigation of the dynamics of AP180-amino-terminal-homology (ANTH) recruitment during CCV formation has been hampered by CALM toxicity upon overexpression. We used knock-in gene editing to express a C-terminal-attached fluorescent version of CALM, while preserving its endogenous expression levels, and cutting-edge live-cell microscopy approaches to study CALM recruitment at forming CCVs. Our results demonstrate that CALM promotes vesicle completion upon membrane tension increase as a function of the amount of this adaptor present. Since the expression of adaptors, including CALM, differs among cells, our data support a model in which the efficiency of clathrin-mediated endocytosis is tissue specific and explain why CALM is essential during embryogenesis and red blood cell development.

• Authors: Nathan M Willy, Federico Colombo, Scott Huber, Anna C Smith, Erienne G Norton, Comert Kural, Emanuele Cocucci
• Journal: Proceedings of the National Academy of Sciences of the United States of America (Proc Natl Acad Sci U S A) Vol. 118 Issue 25 (06 22 2021) ISSN: 1091-6490 [Electronic] United States
• PMID: 34155137 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Adaptor Protein Complex 2
• Monomeric Clathrin Assembly Proteins
• PICALM protein, human
• enhanced green fluorescent protein
• Green Fluorescent Proteins

Topics

• Adaptor Protein Complex 2 (metabolism)
• Biomechanical Phenomena
• Cell Line, Tumor
• Cell Membrane (metabolism)
• Clathrin-Coated Vesicles (metabolism)
• Gene Editing
• Green Fluorescent Proteins (metabolism)
• Humans
• Monomeric Clathrin Assembly Proteins (metabolism)