ALK1 regulates the internalization of endoglin and the type III TGF-β receptor

Complex formation and endocytosis of transforming growth factor-β (TGF-β) receptors play important roles in signaling. However, their interdependence remained unexplored. Here, we demonstrate that ALK1, a TGF-β type I receptor prevalent in endothelial cells, forms stable complexes at the cell surface with endoglin and with type III TGF-β receptors (TβRIII). We show that ALK1 undergoes clathrin-mediated endocytosis (CME) faster than ALK5, type II TGF-β receptor (TβRII), endoglin, or TβRIII. These complexes regulate the endocytosis of the TGF-β receptors, with a major effect mediated by ALK1. Thus, ALK1 enhances the endocytosis of TβRIII and endoglin, while ALK5 and TβRII mildly enhance endoglin, but not TβRIII, internalization. Conversely, the slowly endocytosed endoglin has no effect on the endocytosis of either ALK1, ALK5, or TβRII, while TβRIII has a differential effect, slowing the internalization of ALK5 and TβRII, but not ALK1. Such effects may be relevant to signaling, as BMP9-mediated Smad1/5/8 phosphorylation is inhibited by CME blockade in endothelial cells. We propose a model that links TGF-β receptor oligomerization and endocytosis, based on which endocytosis signals are exposed/functional in specific receptor complexes. This has broad implications for signaling, implying that complex formation among various receptors regulates their surface levels and signaling intensities.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:32

Enthalten in:

Molecular biology of the cell - 32(2021), 7 vom: 01. Apr., Seite 605-621

Sprache:

Englisch

Beteiligte Personen:

Tazat, Keren [VerfasserIn]
Pomeraniec-Abudy, Leslie [VerfasserIn]
Hector-Greene, Melissa [VerfasserIn]
Szilágyi, Szabina Szófia [VerfasserIn]
Sharma, Swati [VerfasserIn]
Cai, Elise M [VerfasserIn]
Corona, Armando L [VerfasserIn]
Ehrlich, Marcelo [VerfasserIn]
Blobe, Gerard C [VerfasserIn]
Henis, Yoav I [VerfasserIn]

Links:

Volltext

Themen:

145170-29-2
ACVRL1 protein, human
Activin Receptors, Type II
Betaglycan
EC 2.7.11.1
EC 2.7.11.30
ENG protein, human
Endoglin
Journal Article
Protein Serine-Threonine Kinases
Proteoglycans
Receptor, Transforming Growth Factor-beta Type I
Receptor, Transforming Growth Factor-beta Type II
Receptors, Transforming Growth Factor beta
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
TGFBR1 protein, human
TGFBR2 protein, human
Transforming Growth Factor beta

Anmerkungen:

Date Completed 15.09.2021

Date Revised 04.12.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1091/mbc.E20-03-0199

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM321268016