mTagBFP2 Fused to Human PCNA
Blue fluorescent proteins are notorious for being very dim and having low photostability. Newly developed coral derivatives emitting in the blue region may improve multicolor imaging using fluorescent proteins that require blue as one of the complementary colors. mTagBFP and the improved mTagBFP2 are bright and photostable coral derivatives that may serve as useful blue markers in live-cell imaging. The cell culture presented in the digital image above is shown expressing a mEmerald fusion tag with proliferating cell nuclear antigen (PCNA), highlighting replication centers in the nuclei of cells in early G1 and S phase of the cell cycle. PCNA, which is a cofactor of DNA polymerase delta, is important for the synthesis of DNA and its repair.