What is the Ubricvitation of Protein?

Protein ubiquitination is a regulatory process that occurs in a cell for degradation of protein molecules. During the process, small proteins known as ubiquitins are associated with protein molecules to be degraded. These ubiquitin molecules effectively indicate protein to degrade with proteosome or protein degrader. There are several steps in protein quarters, all of which are important for normal cellular processes, as cells constantly create and degrade new proteins in response to environmental changes. This step in protein quarters is energy dependent, which means that the cell requires the cell to spend energy through adenosine triphosphate (ATP). E _{2 or the enzyme conjugating ubiquitin is used in the second step in a process where other chemical r RDOs to eaction known as transsthioesterification.}

Once Ubiquitin has gone through these two steps, it binds to e _{3 or ubikvitin-protein league. In human cells there are more than 100 e 3 enzymes, each of which is specific to one protein, known as a substrate or target protein. Because there are also many E 2 molecules, different combinations of three main enzymes allow a high level of specificity for each substrate. This helps the cell carefully monitor intracellular conditions and streamline the process of choosing protein for degradation. The activated enzyme E 3 is bound to the substrate and the ubikvitin molecule, combines both molecules and performs protein quarters throughout the cell.}

At least three or four ubiquitin molecules are usually needed to signal a protein substrate proteosomom. Other protein quarters can often be achieved by the same e _{3 , which initiates the first addition of the ubikvitin molecule. Once the substrate has a sufficiently long ubiquitin chain, the proteosome fears it and degrades it back into the amino acids, building blocks for larger protrumeiny.}

Protein ubiquitination does not always signal the molecule for degradation. The ubiquitin molecules sometimes direct the substrate to move to another part of the cell, while at other times they simply change its function. When ubiquitin is used for these signal purposes, it is generally present as only one connected unit, although there are several rare cases where more than one ubiquitin molecule will still act to modify, unlike degradation. Cells also contain special enzymes known as deubicitinases that can remove ubiquitin molecules from marked proteins and reverse the process.