5 results about "Marker enzymes" patented technology

The invention relates to a method for marking neurons and application of the neurons to unicellular reconstruction of the neurons. The method comprises the following steps: expressing a proximity marker enzyme with enhanced solubility in a target neuron, and providing biotin to the target neuron so as to form biotinylated protein in the neuron; carrying out integral sample dyeing on the biotinylated protein by using monovalent streptavidin coupled with a detectable marker; imaging the dyed sample to obtain a neuron structure image; and reconstructing the morphological structure of the single neuron based on the image data.

The invention discloses a polymer enzyme-labeled secondary antibody compound, a preparation method and an immunodetection kit, and relates to the technical field of immunodetection. The complex comprises a polymer enzyme cluster and a secondary antibody, the polymer enzyme cluster comprises at least one multi-arm polyethylene glycol skeleton, and the arm tail end of the multi-arm polyethylene glycol skeleton is covalently connected with a plurality of labeled enzyme molecules; the secondary antibody is covalently linked with the polymer enzyme cluster through a polyethylene glycol connecting bridge molecule, or covalently linked with an activating group of the polymer enzyme cluster through a surface functional group of the secondary antibody; the chain length of the polyethylene glycol connecting bridge molecule is smaller than that of the arm forming the multi-arm polyethylene glycol skeleton. According to the invention, PEG chains with different lengths are used for connecting the labeled enzyme and the antibody, so that the contradiction that high signal amplification and high enzyme activity retention, high sensitivity and low background, and large-size compounds and good tissue penetrability are difficult to consider at the same time in the prior art is solved; and in the immunodetection, the excellent comprehensive performance of high sensitivity, strong specificity and low background staining is shown.

The invention belongs to the technical field of cellular neurobiology, and relates to a method for capturing a dynamic interaction group of fusion protein and intracellular amyloid protein and application of the method. In the capturing method, the fusion protein is formed by fusing tandem repeat amyloid protein and proximity marker enzyme through flexible connecting peptide; through the design of the tandem repeat sequence of the amyloid A beta, the flexible connecting peptide, the proximity marker enzyme and the like, the local multivalence of the protein is remarkably improved, the saturation concentration required by phase separation is further reduced exponentially, more and more lasting liquid condensates can be stably formed in cells, and the phase separation efficiency is improved. Thus, the metastable oligomer droplets formed by the liquid aggregate are stabilized under physiological conditions. Fluorescence bleaching recovery verifies that the agglomerate generated by the method has pathological liquid-solid phase change characteristics (no fluorescence recovery), and successfully simulates the aging process of amyloid protein. The invention provides a powerful tool for researching a phase separation mediated pathogenic mechanism in amyloid protein related neurodegenerative diseases (such as Alzheimer's disease) and screening a therapeutic drug for agglutinate aging or protein hijacking.

Disclosed are compositions comprising a ligandable tag, a linker, and a labeling enzyme, wherein the linker attaches the ligandable tag to the labeling enzyme. Disclosed are nucleic acid sequences capable of encoding one or more of the disclosed protein based compositions. Disclosed are compositions comprising a ligand conjugated to a molecule of interest. Disclosed are systems comprising a labeling composition and a targeting composition, wherein the labeling composition comprises a ligandable tag, a linker, and a labeling enzyme, wherein the linker attaches the ligandable tag to the labeling enzyme, wherein the targeting composition comprises a ligand conjugated to a molecule of interest, wherein the ligand of the targeting composition is a ligand for the ligandable tag of the labeling composition. Disclosed are methods of using the disclosed compositions and systems.

The present invention relates to a nanobody-proximity labeling enzyme fusion protein and the use thereof. Specifically, provided is a fusion protein used for proximity labeling; the fusion protein comprises (a) a nanobody and (b) a proximity labeling enzyme which are operably linked; optionally, there is a peptide linker between the nanobody and the proximity labeling enzyme. The nanobody-proximity labeling enzyme fusion protein is obtained by means of in vitro expression and purification; and said fusion protein uses an antibody to target a target protein, and therefore is not dependent on an overexpression system and is compatible with various types of cells, tissue and clinically immobilized specimens. The fusion protein can target to proteins having post-translational modifications and various organelles, such as membraneless organelles, and can reach a 100% accuracy of localization.