Ubiquitin is a 76aa polypeptide expressed in all eukaryotic cells, highly conserved from yeast to humans.
The modification of proteins by chains of ubiquitin mediates targeting of cytosolic and nuclear proteins for degradation by proteasomes.
Ubiquitination represents an essential cellular process affected by a multi-enzyme cascade involving classes of enzymes known as ubiquitin-activating enzymes (E1s), ubiquitin-conjugating enzymes (E2s or Ubcs) and ubiquitin-protein ligases (E3s).
E1 activates ubiquitin in an ATP-dependent manner with the formation of a thiol-ester linkage between the C-terminal of ubiquitin and E1.
Sequential, transient thiol-ester bonds then generate between the C-terminal of ubiquitin and specific cysteines of E2 and E3 enzymes.
These bonds culminate in the formation of an isopeptide linkage between the activated C-terminal of ubiquitin and the epsilon-amino group of a lysine on a target protein, or within another ubiquitin chain (usually K48 of ubiquitin) resulting in the generation of chains of ubiquitin (polyubiquitin or multiubiquitin) from 4-20 ubiquitin moieties.
Although the formation of K48-linked polyubiquitin chains on proteins constitutes a potent targeting signal for degradation in 26S proteasomes, ubiquitination is also reversible, and a number of not fully characterized deubiquitinating enzymes exist free in the cytosol.
Research exploring how proteasome targets ER-retained proteins for degradation suggests that ER chaperones (such as Cne1p/calnexin, Kar2p/BiP or other components of the protein processing or transport machineries) helped by cytosolic chaperones (such as members of the Hsp70 and DnaJ families) recognize, target and force misfolded, unassembled or aberrantly modified proteins through the translocon.
The retrotranslocated polypeptide chains are then released into the cytosol as soluble proteins or remain adhered to the cytosolic face of the ER membrane where deglycosylation and polyubiquitination followed by binding to the proteasome as well as degradation to peptides occurs.
Ubiquitination also participates in the internalization and degradation of plasma membrane proteins such as some of the TCR subunits while still ER-membrane associated.
Applications:Suitable for use in Flow Cytometry.
Other applications not tested.
Recommended Dilution:Flow Cytometry: 1:20Optimal dilutions to be determined by the researcher.
Storage and Stability:May be stored at 4°C for short-term only.
Aliquot to avoid repeated freezing and thawing.
Store at -20°C.
Aliquots are stable for 12 months after receipt.
For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
仕様
Size：50ug
Host：rabbit
Source Antibody：bovine
Grade：Affinity Purified
Purity：Purified by Protein A affinity chromatography.
Form：Supplied as a liquid in PBS, 0.09% sodium azide. Labeled with DyLight®488
