BCAR3

Breast tumors are initially dependent on estrogens for growth and progression and can be inhibited by anti-estrogens such as tamoxifen. However, breast cancers progress to become anti-estrogen resistant. Breast cancer anti-estrogen resistance gene 3 was identified in the search for genes involved in the development of estrogen resistance. The gene encodes a component of intracellular signal transduction that causes estrogen-independent proliferation in human breast cancer cells. The protein contains a putative src homology 2 (SH2) domain, a hall mark of cellular tyrosine kinase signaling molecules, and is partly homologous to the cell division cycle protein CDC48. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2012]

BCAR3, NSP Family Adaptor Protein

Acts as an adapter protein downstream of several growth factor receptors to promote cell proliferation, migration, and redistribution of actin fibers (PubMed:24216110).
Specifically involved in INS/insulin signaling pathway by mediating MAPK1/ERK2-MAPK3/ERK1 activation and DNA synthesis (PubMed:24216110).
Promotes insulin-mediated membrane ruffling (By similarity).
In response to vasoconstrictor peptide EDN1, involved in the activation of RAP1 downstream of PTK2B via interaction with phosphorylated BCAR1 (PubMed:19086031).
Inhibits cell migration and invasion via regulation of TGFB-mediated matrix digestion, actin filament rearrangement, and inhibition of invadopodia activity (By similarity).
May inhibit TGFB-SMAD signaling, via facilitating BCAR1 and SMAD2 and/or SMAD3 interaction (By similarity).
Regulates EGF-induced DNA synthesis (PubMed:18722344).
Required for the maintenance of ocular lens morphology and structural integrity, potentially via regulation of focal adhesion complex signaling (By similarity).
Acts upstream of PTPRA to regulate the localization of BCAR1 and PTPRA to focal adhesions, via regulation of SRC-mediated phosphorylation of PTPRA (By similarity).
Positively regulates integrin-induced tyrosine phosphorylation of BCAR1 (By similarity).
Acts as a guanine nucleotide exchange factor (GEF) for small GTPases RALA, RAP1A and RRAS (By similarity).
However, in a contrasting study, lacks GEF activity towards RAP1 (PubMed:22081014).

Endothelin receptor signaling pathway Source: UniProtKB
Insulin receptor signaling pathway Source: UniProtKB
Lens morphogenesis in camera-type eye Source: Ensembl
Positive regulation of DNA replication Source: UniProtKB
Positive regulation of epidermal growth factor receptor signaling pathway Source: UniProtKB
Positive regulation of GTPase activity Source: UniProtKB
Positive regulation of MAPK cascade Source: UniProtKB
Positive regulation of peptidyl-serine phosphorylation Source: GO_Central
Response to drug Source: ProtInc
Signal transduction Source: ProtInc
Small GTPase mediated signal transduction Source: InterPro

Cytoplasm; Focal adhesion. Localization to focal adhesions depends on interaction with PTPRA.

Phosphorylated on tyrosine residues.