MRGSHHHHHH GMASMTGGQQ MGRDLYDDDD KDRWGSMANI AVQRIKREFK EVLKSEETSK NQIKVDLVDE NFTELRGEIA GPPDTPYEGG RYQLEIKIPE TYPFNPPKVR FITKIWHPNI SSVTGAICLD ILKDQWAAAM TLRTVLLSLQ ALLAAAEPDD PQDAVVANQY KQNPEMFKQT ARLWAHVYAG APVSSPEYTK KIENLCAMGF DRNAVIVALS SKSWDVETAT ELLLSN.
Ubiquitin-Conjugating Enzyme E2K, also known as UBE2K, is a crucial component of the ubiquitination pathway, which is essential for regulating protein turnover and maintaining cellular homeostasis. This enzyme is part of the E2 family of ubiquitin-conjugating enzymes, which play a central role in the ubiquitination process by transferring ubiquitin from the E1 activating enzyme to the substrate protein, often with the help of an E3 ligase .
The preparation of human recombinant Ubiquitin-Conjugating Enzyme E2K typically involves recombinant DNA technology. The gene encoding UBE2K is cloned into an expression vector, which is then introduced into a suitable host cell, such as Escherichia coli or yeast. The host cells are cultured under conditions that promote the expression of the recombinant protein. After expression, the protein is purified using techniques such as affinity chromatography, which exploits the specific binding properties of the protein to isolate it from other cellular components .
The ubiquitination process involves a series of enzymatic reactions that tag proteins with ubiquitin, marking them for degradation by the proteasome. The process begins with the activation of ubiquitin by an E1 enzyme, which forms a thioester bond with ubiquitin. The activated ubiquitin is then transferred to the active-site cysteine of the E2 enzyme, including UBE2K, via a transthiolation reaction .
UBE2K, in conjunction with an E3 ligase, facilitates the transfer of ubiquitin to the substrate protein. The E3 ligase binds both the E2-ubiquitin complex and the substrate, positioning them for the transfer of ubiquitin to a lysine residue on the substrate protein. This ubiquitination can result in the formation of polyubiquitin chains, which signal the proteasome to degrade the tagged protein .
UBE2K is involved in various cellular processes, including the regulation of protein degradation, cell cycle progression, and response to stress. Dysregulation of ubiquitination can lead to various diseases, including cancer, neurodegenerative disorders, and immune system dysfunctions. Therefore, understanding the function and regulation of UBE2K is crucial for developing therapeutic strategies targeting these pathways .