Dr. Yury Chernoff
Associate Professor
School of Biology
Dr. Yury Chernoff
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Contact information:
- School of Biology
- 315 Ferst Drive
- IBB, Room 2304
- Atlanta, GA 30332, Mail Code: 0230
- Tel: 404-894-1157
- Fax: 404-894-0519
- Email:
Research Interests
Yeast molecular genetics: genetic control of protein biosynthesis, folding and aggregation; prions and protein-based inheritance; chaperones and stress response
Current Research
Prions were initially identified as proteins in an unusual conformation that cause neurodegenerative diseases in mammals, including humans. Infection depends on the prion's ability to convert an unmodified non-prion protein, encoded by the same host maintenance gene, into the prion conformation. Prion proteins form ordered fibrous aggregates, resembling those involved in other neural inclusion diseases, such as Huntington's disease or Alzheimer's disease. Moreover, many non-prion proteins can form amyloids in specific conditions. It is thought that amyloids represent one of the ancient types of the protein fold.
Some yeast non-Mendelian heritable elements, such as [URE3], [PSI+] or [RNQ+], closely resemble mammalian prions. This shows that heritable information can be coded in protein structures, in addition to information coded in the DNA sequence. Therefore, prions provide a basis for the protein-based inheritance in yeast (and possibly in other organisms).
Protein aggregates behave as "molecular tumors" at the subcellular level. While most aggregated proteins form "non-malignant tumors", prions form the "malignant tumors" that can spread to other cells. We have shown that the ability of the yeast prions to spread depends on the chaperone helpers producing the infectious "seeds". In this way, prions use the cellular stress defense systems to their own advantage. Chaperones could become potential targets in counteracting the prion diseases and other aggregation-related disorders.
Our current research is focused on the following topics: 1) role of the specific chaperones of the Hsp70 and Hsp100 groups, proteolytic systems and cytoskeletal assembly networks in formation and propagation of yeast prions; 2) molecular evolution of yeast prion proteins, and mechanisms of the so-called "species barrier" that prevents transmission of the amyloid state between related proteins of divergent amino acid sequences; 3) using yeast as a model system for studying mechanisms of aggregation and toxicity of proteins involved in mammalian neural inclusion diseases.