I am using Click-iT AHA (L-azidohomoalanine) kit to label nascent proteins in live cells, then detecting with TAMRA alkyne after fixation and permeabilization and a click reaction. But I'm seeing nucleolar labeling in the cells. It this expected?
Yes. All proteins synthesized during the time the AHA is present will be detected, and they may be all over the cell. Our imaging shows strong labeling in the nucleoli and cytoplasm, as well as nuclear labeling.
Selective identification of newly synthesized proteins in mammalian cells using bioorthogonal noncanonical amino acid tagging (BONCAT).
Authors:Schuman EM
Journal:Proceedings of the National Academy of Sciences of the United States of America
PubMed ID:16769897
In both normal and pathological states, cells respond rapidly to environmental cues by synthesizing new proteins. The selective identification of a newly synthesized proteome has been hindered by the basic fact that all proteins, new and old, share the same pool of amino acids and thus are chemically indistinguishable. We ... More
In situ visualization and dynamics of newly synthesized proteins in rat hippocampal neurons.
Authors:Schuman EM
Journal:Nature neuroscience
PubMed ID:20543841
Protein translation has been implicated in different forms of synaptic plasticity, but direct in situ visualization of new proteins is limited to one or two proteins at a time. Here we describe a metabolic labeling approach based on incorporation of noncanonical amino acids into proteins followed by chemoselective fluorescence tagging ... More
Two-color labeling of temporally defined protein populations in mammalian cells.
Authors:Tirrell DA
Journal:Bioorganic & medicinal chemistry letters
PubMed ID:18774715
The proteome undergoes complex changes in response to disease, drug treatment, and normal cellular signaling processes. Characterization of such changes requires methods for time-resolved protein identification and imaging. Here, we describe the application of two reactive methionine (Met) analogues, azidohomoalanine (Aha) and homopropargylglycine (Hpg), to label two protein populations in ... More
Fluorescence visualization of newly synthesized proteins in mammalian cells.
Authors:Tirrell DA
Journal:Angewandte Chemie (International ed. in English)
PubMed ID:17036290
Noncanonical amino acid tagging enables the selective fluorescent visualization of newly synthesized proteins in mammalian cells (see the picture). Susceptibility to tagging is determined by the spatial and temporal character of the protein synthesis, thus providing a complement to methods which identify relevant members of the proteome. ... More
Spatial coupling of mTOR and autophagy augments secretory phenotypes.
Authors:Narita M., et al
Journal:Science (New York, N.Y.)
PubMed ID:21512002
Protein synthesis and autophagic degradation are regulated in an opposite manner by mammalian target of rapamycin (mTOR), whereas under certain conditions it would be beneficial if they occurred in unison to handle rapid protein turnover. We observed a distinct cellular compartment at the trans side of the Golgi apparatus, the ... More