Targeted Protein Degradation Method Based On Trim21-mediated Ubiquitination

Proteins are essential constituents of which all living organisms are compsed.Its expression and degradation are fundamental to cell function and physiological status of organisms.In general,the protein level is precisely regulated by the regulatory network.However,in some cases,abnormal expression and misfolding of protein might occur and often lead to abnormal accumulation of dysfunctional protein in cells,subsequently leading to the development of various diseases.Therefore,protein interference technology should be explored,to provide not only important means to analyse the function of proteins,but also effective prevention and treatment strategies for diseases caused by protein dysfunction.Among multiple endogenous protein degradation pathways,the ubiquitin-proteasome pathway is the foremost pathway in the human body with high efficiency and specificity.Thus,redirection of the ubiquitin-proteasome pathway for degradation of target proteins has become the focus of researches.Over the past two decades,targeted protein degradation technologies,such as technologies of E3 ligase modification and PROTACs technology,have successfully re-oriented the ubiquitin-proteasome pathway and thus degraded many pathogenic proteins and even "undruggable" targets,showing great potential and clinical value.In the present research,we proposed a novel protein degration technology by integrating the function of E3 ligase Trim21 and expression of chimeric antibody.This degradation system was termed Pr.Predator.To demonstrate the degradation efficiency of Predator system,two protein targets,free GFP and membrane protein Erb B3 were chosen.we designed cooresponding Predator system and explored its degradation ability both at the molecular,signaling and cellular levels.Moreover,ligands-receptor interaction was introduced to glucagon receptor Predator system,and we demonstrated that ligands-based target module is capable of target recognition and degradation.In conclusion,the design and exploration of the Predator system in this research can provide references for the design of ubiquitination-based protein degradation technology and a new technical method for lossof-function research of life science.Also,Predator system might exhibit a novel approach for protein dysfunction-related clinical treatment.