Fluorescent proteins (FPs) have been used as protein tags since the mid-1990s mainly for cell biology and fluorescence microscopy. These tags have not only revolutionized cell biology by enabling the imaging of almost any protein, they are also used in biochemical applications. An important example is the immunoprecipitation and affinity purification of FP-tagged proteins, which was enabled by the development of affinity resins with high yield, purity, and affinity such as ChromoTek’s Nano-Traps (https://www.chromotek.com/products/detail/product-detail/nano-traps/).
In this blog we provide a review of
Chromotek’s GFP- binding protein, an anti- GFP Nanobody, is a very small and effective tool for binding and visualizing GFP-tagged proteins. In their recent publication, Modi et al. successfully functionalized quantum dots with the GFP- Nanobody (QD GFP- Nanobody). Thus, they created a small GFP- specific label with a very strong fluorescent signal.
What makes on-bead digestion favorable?
Just pull down your protein of interest with immobilized nanobodies, also termed VHHs or single domain antibodies. Then follow the on-bead digestion protocol (see below) and submit the digest to your core facility for effective mass spectrometer analysis of (co-) precipitated proteins.
Life science laboratories apply green fluorescent proteins (GFP) to study protein localization, interaction and dynamics in fluorescence microscopy. Immunoprecipitation (IP), mass spectrometry (MS), co-immunoprecipitation (Co-IP) and/or affinity purification investigate more aspects including posttranslational modifications (PTMs), DNA binding, and protein-protein interaction. Here, we compare two different antibody systems for immunoprecipitation of GFP-fusion proteins: GFP-Trap and anti-GFP IgG antibody
ChromoTek Nano-Boosters are ideal for Super-Resolution and “traditional” fluorescence microscopy because of their high affinity and extremely small size of just 2 to 3 nm. Technically speaking, the GFP-and RFP-Boosters are composed of the highly specific GFP- or RFP-binding domains of alpaca antibodies (also called “nanobodies”), covalently coupled to a selection of fluorescent dyes.