About TCF7
This gene encodes a member of the T-cell factor/lymphoid enhancer-binding factor family of high mobility group (HMG) box transcriptional activators. This gene is expressed predominantly in T-cells and plays a critical role in natural killer cell and innate lymphoid cell development. The encoded protein forms a complex with beta-catenin and activates transcription through a Wnt/beta-catenin signaling pathway. Mice with a knockout of this gene are viable and fertile, but display a block in T-lymphocyte differentiation. Alternative splicing results in multiple transcript variants. Naturally-occurring isoforms lacking the N-terminal beta-catenin interaction domain may act as dominant negative regulators of Wnt signaling. [provided by RefSeq, Oct 2016]

About Alexa Fluor 555
Alexa Fluor™ 555 (AF555, Alexa 555) has an excitation peak at 555 nm and an emission peak at 565 nm, and is spectrally similar to Cy®3 (GE Healthcare), TRITC, iFluor® 555 (ATT Bioquest) and iFluor® 560 (ATT Bioquest). Many flow cytometers are equipped with 532nm lasers, so while Alexa 555 can be used for flow cytometry, PE is more commonly used due to its brightness and spectral characteristics. This dye is commonly used for fluorescence microscopy applications.