Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Split-Inteins for Simultaneous, site-specific conjugation of Quantum Dots to multiple protein targets In vivo | Charalambous et al. Journal of Nanobiotechnology 2011 9 37 http content 9 1 37 JOURNAL OF NANOBIOTECHNOLOGY RESEARCH Open Access Split-Inteins for Simultaneous site-specific conjugation of Quantum Dots to multiple protein targets In vivo Anna Charalambousf Ioanna Antoniadesf Neophytos Christodoulou and Paris A Skourides Abstract Background Proteins labelled with Quantum Dots QDs can be imaged over long periods of time with ultrahigh spatial and temporal resolution yielding important information on the spatiotemporal dynamics of proteins within live cells or in vivo. However one of the major problems regarding the use of QDs for biological imaging is the difficulty of targeting QDs onto proteins. We have recently developed a DnaE split intein-based method to conjugate Quantum Dots QDs to the C-terminus of target proteins in vivo. In this study we expand this approach to achieve site-specific conjugation of QDs to two or more proteins simultaneously with spectrally distinguishable QDs for multiparameter imaging of cellular functions. Results Using the DnaE split intein we target QDs to the C-terminus of paxillin and show that paxillin-QD conjugates become localized at focal adhesions allowing imaging of the formation and dissolution of these complexes. We go on to utilize a different split intein namely Ssp DnaB mini-intein to demonstrate N-terminal protein tagging with QDs. Combination of these two intein systems allowed us to simultaneously target two distinct proteins with spectrally distinguishable QDs in vivo without any cross talk between the two intein systems. Conclusions Multiple target labeling is a unique feature of the intein based methodology which sets it apart from existing tagging methodologies in that given the large number of characterized split inteins the number of individual targets that can be simultaneously tagged is only limited by the number of QDs that can be spectrally distinguished within the cell. Therefore the
