Biophysical investigations of the interaction between substrate binding domain of Hsp40 and the RING finger domain of Retinoblastoma Binding Protein 6

Irrespective of the tireless efforts and resources that have been pumped into cancer elimination and management, the disease remains one of the foremost causes of death worldwide, with associated mortality and morbidity cases on the rise every year. The disease has therefore become a major public health concern as both the young and aged are greatly affected. For years, efforts have been directed towards finding permanent solutions for cancer, not only because of the risk of reoccurrence but also due to the non-specificity and side effects of current chemotherapy treatments. Protein-protein interactions have recently come onto the scene as potential targets for novel treatment and management options for the disease. Through a yeast-two hybrid study, the RING finger domain of the Retinoblastoma binding protein 6 (RBBP6) and the substrate binding domain of heat shock protein 40 (SBDHsp40) suggested a putative interaction between these two proteins. In this study molecular dynamic simulations were used to confirm the interaction between the proteins and associated binding parameters. This was followed by the recombinant expression of the proteins within two difference expression vectors and E. coli bacterial strains. The SBDHsp40 protein was purified using affinity chromatography while the RING finger domain protein was purified to homogeneity by affinity and size exclusion chromatography. Biophysical characterization in the form of Fourier Transform–infrared spectroscopy and Raman spectroscopy were then used to determine the functional groups within the proteins that made up their secondary structural elements. Due to time constraints, the experimental interactive studies could not be performed. However, the in-silico studies done confirm this putative interaction and form a basis for consequent application in the discovery of new anti-cancer drugs. Keywords: Cancer, heat shock protein 40 (Hsp40), protein-protein interaction (PPI), retinoblastoma-binding protein-6 (RBBP6), RING finger domain, substrate binding domain, ubiquitination.

Grantor dc:publisher.institution

Univeristy of Zululand

Year dc:date.issued

2022

Author dc:creator

• Mdunge, Sanele Maud Nondumiso

• Heat shock protein 40 (Hsp40)
• Protein-protein interaction (PPI)
• RING finger domain
• Ubiquitination

Licence

• https://devspace.unizulu.ac.za/bitstreams/094e8fce-c472-4e09-bf21-8fc32a8dddef/download