Temporal Dynamics of VEGFA-Induced VEGFR2/FAK Co-Localization Depend on SHB
1
Department of Medical Cell Biology, Uppsala University, Box 571, 75123 Uppsala, Sweden
2
Present address: Department of Immunology, Genetics and Pathology, Uppsala University, 75108 Uppsala, Sweden
3
Institute of Molecular Genetics of the CAS, 14220 Prague, Czech Republic
4
Department of Immunology, Genetics and Pathology, Uppsala University, 75108 Uppsala, Sweden
*
Author to whom correspondence should be addressed.
Cells 2019, 8(12), 1645; https://doi.org/10.3390/cells8121645
Received: 14 November 2019 / Revised: 12 December 2019 / Accepted: 13 December 2019 / Published: 15 December 2019
(This article belongs to the Special Issue Vascular Signalling)
Focal adhesion kinase (FAK) is essential for vascular endothelial growth factor-A (VEGFA)/VEGF receptor-2 (VEGFR2)-stimulated angiogenesis and vascular permeability. We have previously noted that presence of the Src homology-2 domain adapter protein B (SHB) is of relevance for VEGFA-stimulated angiogenesis in a FAK-dependent manner. The current study was conducted in order address the temporal dynamics of co-localization between these components in HEK293 and primary lung endothelial cells (EC) by total internal reflection fluorescence microscopy (TIRF). An early (<2.5 min) VEGFA-induced increase in VEGFR2 co-localization with SHB was dependent on tyrosine 1175 in VEGFR2. VEGFA also enhanced SHB co-localization with FAK. FAK co-localization with VEGFR2 was dependent on SHB since it was significantly lower in SHB deficient EC after VEGFA addition. Absence of SHB also resulted in a gradual decline of VEGFR2 co-localization with FAK under basal (prior to VEGFA addition) conditions. A similar basal response was observed with expression of the Y1175F-VEGFR2 mutant in wild type EC. The distribution of focal adhesions in SHB-deficient EC was altered with a primarily perinuclear location. These live cell data implicate SHB as a key component regulating FAK activity in response to VEGFA/VEGFR2.
Keywords:
VEGFR2; FAK; SHB; TIRF; focal adhesions; angiogenesis