Grey Fox Lung Cells with mEmerald-α-Actinin and mCherry-PDHA1
Actin filaments are organized into various types of packages and gel-like networks in animal cells. The form that the cytoskeletal filaments take depends on the function they are expected to carry out and the type of proteins that bind them. For example, in the microspikes, actin filaments are organized into tight parallel bundles by fimbrin, which possesses actin-binding sites located closely to one another in the polypeptide chain.
PDHA1 is a pyruvate dehydrogenase complex enzyme often utilized in microscopy applications as a mitochondrial marker. The complex that the enzyme forms with dihydrolipoyl transacetylase (DLAT) and dihydrolipoyl dehydrogenase (DLD) is involved in catalyzing the conversion of pyruvate to acetyl-CoA. The featured fox lung cells are shown expressing mCherry fused to PDHA1 and mEmerald fused to alpha-actinin. Cellular structures rich in actin, such as stress fibers, are highlighted by the latter fusion because alpha-actinin is an actin-binding protein.
The green fluorescent protein mEmerald exhibits peak excitation at 487 nanometers and peak emission at 509 nanometers. Both the brightness and photostability of mEmerald are greater than that of EGFP, from which it was derived. mCherry is a red fluorescent protein generated by the directed evolution of mRFP1. Excitation and emission maxima of mCherry occur at 587 and 610 nanometers, respectively.