Details

Autor(en) / Beteiligte

• Varadaraj, Archana
• Jenkins, Laura M
• Singh, Priyanka
• Chanda, Anindya
• Snider, John
• Lee, N Y
• Amsalem-Zafran, Ayelet R
• Ehrlich, Marcelo
• Henis, Yoav I
• Mythreye, Karthikeyan
• Luo, Kunxin

Titel

TGF-β triggers rapid fibrillogenesis via a novel TβRII-dependent fibronectin-trafficking mechanism

Ist Teil von

• Molecular biology of the cell, 2017-05, Vol.28 (9), p.1195-1207

Ort / Verlag

United States: The American Society for Cell Biology

Erscheinungsjahr

2017

Quelle

MEDLINE

Beschreibungen/Notizen

• Fibronectin (FN) is a critical regulator of extracellular matrix (ECM) remodeling through its availability and stepwise polymerization for fibrillogenesis. Availability of FN is regulated by its synthesis and turnover, and fibrillogenesis is a multistep, integrin-dependent process essential for cell migration, proliferation, and tissue function. Transforming growth factor β (TGF-β) is an established regulator of ECM remodeling via transcriptional control of ECM proteins. Here we show that TGF-β, through increased FN trafficking in a transcription- and SMAD-independent manner, is a direct and rapid inducer of the fibrillogenesis required for TGF-β-induced cell migration. Whereas TGF-β signaling is dispensable for rapid fibrillogenesis, stable interactions between the cytoplasmic domain of the type II TGF-β receptor (TβRII) and the FN receptor (α5β1 integrin) are required. We find that, in response to TGF-β, cell surface-internalized FN is not degraded by the lysosome but instead undergoes recycling and incorporation into fibrils, a process dependent on TβRII. These findings are the first to show direct use of trafficked and recycled FN for fibrillogenesis, with a striking role for TGF-β in this process. Given the significant physiological consequences associated with FN availability and polymerization, our findings provide new insights into the regulation of fibrillogenesis for cellular homeostasis.