Receptor and Molecular Mechanism of AGGF1 Signaling in Endothelial Cell Functions and Angiogenesis.

Abstract

Objective:

Angiogenic factor AGGF1 (angiogenic factor with G-patch and FHA [Forkhead-associated] domain 1) promotes angiogenesis as potently as VEGFA (vascular endothelial growth factor A) and regulates endothelial cell (EC) proliferation, migration, specification of multipotent hemangioblasts and venous ECs, hematopoiesis, and vascular development and causes vascular disease Klippel-Trenaunay syndrome when mutated. However, the receptor for AGGF1 and the underlying molecular mechanisms remain to be defined.

Approach and Results:

Using functional blocking studies with neutralizing antibodies, we identified [alpha]5[beta]1 as the receptor for AGGF1 on ECs. AGGF1 interacts with [alpha]5[beta]1 and activates FAK (focal adhesion kinase), Src (proto-oncogene tyrosine-protein kinase), and AKT (protein kinase B). Functional analysis of 12 serial N-terminal deletions and 13 C-terminal deletions by every 50 amino acids mapped the angiogenic domain of AGGF1 to a domain between amino acids 604-613 (FQRDDAPAS). The angiogenic domain is required for EC adhesion and migration, capillary tube formation, and AKT activation. The deletion of the angiogenic domain eliminated the effects of AGGF1 on therapeutic angiogenesis and increased blood flow in a mouse model for peripheral artery disease. A 40-mer or 15-mer peptide containing the angiogenic domain blocks AGGF1 function, however, a 15-mer peptide containing a single amino acid mutation from -RDD- to -RGD- (a classical RGD integrin-binding motif) failed to block AGGF1 function.

Conclusions:

We have identified integrin [alpha]5[beta]1 as an EC receptor for AGGF1 and a novel AGGF1-mediated signaling pathway of [alpha]5[beta]1-FAK-Src-AKT for angiogenesis. Our results identify an FQRDDAPAS angiogenic domain of AGGF1 crucial for its interaction with [alpha]5[beta]1 and signaling.

• Authors: Jingjing Wang, Huixin Peng, Ayse Anil Timur, Vinay Pasupuleti, Yufeng Yao, Teng Zhang, Sun-Ah You, Chun Fan, Yubing Yu, Xinzhen Jia, Jing Chen, Chengqi Xu, Qiuyun Chen, Qing Wang
• Journal: Arteriosclerosis, thrombosis, and vascular biology (Arterioscler Thromb Vasc Biol) Vol. 41 Issue 11 Pg. 2756-2769 (11 2021) ISSN: 1524-4636 [Electronic] United States
• PMID: 34551592 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• AGGF1 protein, human
• Aggf1 protein, mouse
• Angiogenesis Inducing Agents
• Angiogenic Proteins
• Integrin alpha5beta1
• Ligands
• MAS1 protein, human
• Peptide Fragments
• Proto-Oncogene Mas
• Focal Adhesion Kinase 1
• PTK2 protein, human
• Ptk2 protein, mouse
• src-Family Kinases
• Proto-Oncogene Proteins c-akt

Topics

• 3T3-L1 Cells
• Angiogenesis Inducing Agents (pharmacology)
• Angiogenic Proteins (genetics, metabolism, pharmacology)
• Animals
• Disease Models, Animal
• Endothelial Cells (drug effects, metabolism)
• Female
• Focal Adhesion Kinase 1 (metabolism)
• HEK293 Cells
• HeLa Cells
• Hep G2 Cells
• Hindlimb (blood supply)
• Humans
• Integrin alpha5beta1 (genetics, metabolism)
• Ischemia (drug therapy, genetics, metabolism, physiopathology)
• Ligands
• Male
• Mice
• Mice, Inbred C57BL
• Neovascularization, Physiologic (drug effects)
• Peptide Fragments (pharmacology)
• Phosphorylation
• Protein Interaction Domains and Motifs
• Proto-Oncogene Mas
• Proto-Oncogene Proteins c-akt (metabolism)
• Rats
• Signal Transduction
• src-Family Kinases (metabolism)