His6-Poly-Ubiquitinated p53, human recombinant

p53 acts as a tumor suppressor in many tumor types; induces growth arrest or apoptosis depending on the physiological circumstances and cell type. Involved in cell cycle regulation as a trans-activator that acts to negatively regulate cell division by controlling a set of genes required for this process. Prevents CDK7 kinase activity when associated to CAK complex in response to DNA damage, thus stopping cell cycle progression. E3 ligase MDM2 mediated ubiquitin conjugation of p53 and subsequent p53 down-regulation via proteasomal degradation interrupts this crucial role, contributing to tumorogenesis (and cancer). This product consists of His6-p53 protein ubiquitinated by MDM2, and subsequently purified from conjugation-reaction proteins/ enriched post-conjugation. Western blot analysis shows multiple states of poly-ubiquitination, and deconjugation with USP7 shows purified ubiquitinated p53 can function as a native substrate.