An improved smaller biotin ligase for BioID proximity labeling

Abstract

A smaller promiscuous biotin ligase for proximity biotinylation called BioID2 enables more-selective targeting of fusion proteins, requires less biotin supplementation, exhibits enhanced labeling of proximate proteins, and demonstrates the use of a flexible linker to modulate the biotin-labeling radius.

RNA–protein interaction detection in living cells

“…We identified four biotin ligases, in addition to E. coli BirA and Aquifex aeolicus (BioID2), which contain RBAM (Fig. 4a) 34 . Each of the mutant BirA*s were tagged with HA and transfected at equal amounts.…”

Analysis of K-Ras Interactions by Biotin Ligase Tagging

“…We have modified the promiscuous biotin ligase tagging system (85)(86)(87)(88) to analyze the protein interaction networks of the G12D, WT, S17N, and C185S/G12D K-Ras proteins. As shown, our chimeric BirA*Ras proteins were expressed as expected, localized as predicted, and their localization patterns matched the patterns of the proteins they biotinylated (Figures 1-4).…”

Filling the Void: Proximity-Based Labeling of Proteins in Living Cells

“…As the labeling radius of BioID is limited, it can be used to map the population and spatial distribution of proteins within large structures by application to proteins throughout the structure, as was demonstrated at the nuclear pore complex [12]. If a larger labeling radius is desired, for example to capture more constituents within a large protein complex, it can be increased by insertion of flexible linkers between the bait and the ligase [23]. BioID also captures protein associations over a period of time and independent of stable interactions, making it an effective approach in identifying novel substrates of proteins with dynamic and transient protein associations such as the E3 ubiquitin ligase, β-TrCP1 [24].…”