Intracellular Staining by Flow Cytometry
|Detection of Twist‑1 in A549 Human Cell Line by Flow Cytometry. A549 human lung carcinoma cell line was stained with Mouse Anti-Human Twist‑1 Alexa Fluor® 647‑conjugated Monoclonal Antibody (Catalog # IC9160R, filled histogram) or isotype control antibody (Catalog # IC002R, open histogram). To facilitate intracellular staining, cells were fixed with Flow Cytometry Fixation Buffer (Catalog # FC004) and permeabilized with Flow Cytometry Permeabilization/Wash Buffer I (Catalog # FC005). View our protocol for Staining Intracellular Molecules.|
Twist-1 (Twist-related protein 1; also H-Twist and bHLHa38) is a 25‑27 kDa class B member of the bHLH transcription factor family of proteins. It is widely expressed in embryo, and select adult cells such as white adipocytes. In fat, Twist-1 induces fatty acid oxidation via PGC-1 alpha and CPT-1, and promotes MCP-1 and TNF-alpha secretion by adipocytes. In epithelium, Twist-1 dysregulation represses E-Cadherin and induces N-Cadherin expression, resulting in an epithelial-to-mesenchymal transition that can lead to cancer. Human Twist-1 is 202 amino acids (aa) in length. It contains a bHLH domain (aa 109-164) with an embedded DNA-binding motif. Twist-1 forms homodimers, and heterodimerizes with TCF3, HAND 1 and HAND 2. Two distinct mutations exist that may impact its dimerization pattern. There is one seven aa insertion after Ile135, and a second seven aa insertion after Pro139. A third unrelated variant shows a four Gly insert after Gly92. Full-length human Twist-1 shares 98% aa identity with mouse Twist-1.