Rudhira/BCAS3 couples microtubules and intermediate filaments to promote cell migration for angiogenic remodeling

Abstract

Blood vessel formation requires endothelial cell (EC) migration that depends on dynamic remodeling of the cytoskeleton. Rudhira/Breast Carcinoma Amplified Sequence 3 (BCAS3) is a cytoskeletal protein essential for EC migration and sprouting angiogenesis during mouse development and is implicated in metastatic disease. Here, we report that Rudhira mediates cytoskeleton organization and dynamics during EC migration. Rudhira binds to both microtubules (MTs) and vimentin intermediate filaments (IFs) and stabilizes MTs. Rudhira depletion impairs cytoskeletal cross-talk, MT stability, and hence focal adhesion disassembly. The BCAS3 domain of Rudhira is necessary and sufficient for MT-IF cross-linking and cell migration. Pharmacologically restoring MT stability rescues gross cytoskeleton organization and angiogenic sprouting in Rudhira-depleted cells. Our study identifies the novel and essential role of Rudhira in cytoskeletal cross-talk and assigns function to the conserved BCAS3 domain. Targeting Rudhira could allow tissue-restricted cytoskeleton modulation to control cell migration and angiogenesis in development and disease.

Mechanical and Non‐Mechanical Functions of Filamentous and Non‐Filamentous Vimentin

“…In addition to the crosslinker plectin and multiple plus and minus end directed molecular motors [ 16 ] that link VIFs to microtubules, the protein Rudhira/Breast Carcinoma Amplified Sequence 3 (BCAS3) also links vimentin to microtubules and leads to MT stabilization, an effect that is essential for endothelial cell motility, focal adhesion dynamics, and angiogenesis. [ 17 ] Carmil, a protein that interacts with actin capping protein and hence affects actin dynamics also binds VIFs, suggesting a novel link between these two filament systems. [ 18 ] Another actin regulatory protein, girdin, that links protein kinase B (AKT) signaling to cytoskeletal dynamics was shown to bind vimentin by mass spectrometry and immunoprecipitation from pancreatic cancer cells.…”

The proppin Bcas3 and its interactor KinkyA localize to the early phagophore and regulate autophagy

“…S4B, Table S2). DDB_G0272949 is homologous to BCAS3, a gene upregulated in breast cancer and other malignancies [21,22], which is essential for angiogenesis and survival of mouse embryos [23], where BCAS3 localizes to microtubules and intermediate filaments [24,25]. To confirm the interaction of Dictyostelium Bcas3 with KnkA, we coexpressed MYC-tagged Bcas3 with KnkA-YFP in knkA − cells, performed immunoprecipitation with anti-MYC antibodies and probed the size-fractionated precipitate with GFP antibodies, or conversely immunoprecipitated with anti-GFP antibodies and probed the precipitate with anti-MYC antibodies ( Figure 4A).…”

“…bcas3 knockdown prevents cell migration and wound healing [24], while bcas3 knockout mice are embryonic lethal with severe defects in angiogenesis [23]. The BCAS3 domain is both necessary and sufficient for its binding to TUB/tubulin and VIM (vimentin) intermediate filaments and its role in cell migration, while its WD40 repeats have no obvious role [25].…”

GWAS Links New Variant in Long Non-Coding RNA LINC02006 with Colorectal Cancer Susceptibility

“…BCAS3 is a cytoskeletal WD repeat domain-containing protein essential for angiogenesis, both during the developmental process and in tumor metastasis [51,53]. By activating and recruiting cell division cycle 42 (CDC42) Rho-GTPase [54] and facilitating crosstalk between cytoskeleton elements, BCAS3 regulates cell polarity and focal adhesion assembly [55].…”