Engineered p27 Polypeptide for Stable Cdk4 Cyclin D Trimeric Complex
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current inhibitors of cyclin-dependent kinases (Cdk) 4 and 6 face challenges in effectively targeting the active form of these enzymes in cells, particularly due to the technical difficulties in generating the active form of p27, which is essential for forming functional complexes with Cdk4 or Cdk6 and cyclin D.
Innovation Solution
The development of a polypeptide comprising an engineered p27 with specific amino acid substitutions at positions Y74, Y88, and Y89, which forms a trimeric protein complex with Cdk4 or Cdk6 and cyclin D, enhancing the stability and activity of these complexes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the dimeric Cdk4-CycD complex is used for inhibitor screening, then the technical challenges of generating active p27 are avoided, but the complex does not readily form in all cells and certain complexes including p27 may be resistant to treatments
Solution Approach 1:
The patent applies parameter changes by modifying the amino acid sequence of p27 through specific substitutions (Y74, Y88, and Y89 positions) to create an engineered p27 that can be readily produced in active form. This engineering approach changes the biochemical parameters of p27 to enable stable trimeric complex formation with Cdk4/6 and cyclin D, resolving the contradiction between ease of manufacture and reliability of complex formation.
2Ease of manufacture
If inhibitors are developed using Cdk4-CycD dimeric complexes, then production is simplified, but the inhibitors may not effectively target the active trimeric form present in cells
Solution Approach 1:
The patent applies preliminary action by pre-phosphorylating the engineered p27 at specific tyrosine residues (Y74, Y88, Y89) before forming the trimeric complex with Cdk4/6 and cyclin D. This preliminary phosphorylation action ensures that the complex is generated in its active, cellular-relevant form, allowing inhibitors to be screened against the physiologically relevant trimeric structure rather than the simplified dimeric form.
3Reliability
If wild-type p27 is used to form the trimeric complex, then the complex reflects natural structure, but generating the active form presents technical challenges
Solution Approach 1:
The patent introduces an engineered p27 as an intermediary that bridges the gap between wild-type p27 and the active trimeric complex. The engineered p27 contains specific amino acid substitutions that facilitate its production in active form while maintaining the ability to form physiologically relevant trimeric complexes with Cdk4/6 and cyclin D, thus serving as a manufacturable proxy for wild-type p27.
Data Source
AI summary
The disclosure provides polypeptides comprising an engineered p27, or a fragment thereof such polypeptides may be used to form trimeric protein complexes with a cyclin-dependent kinase 4 (Cdk4) (or a variant thereof) or Cdk6 (or a variant thereof), and a cyclin D (CycD) or a variant thereof.