The Ubiquitin System

The conjugation of ubiquitin to other cellular proteins regulates a broad range of eukaryotic cell functions, including protein degradation, cell cycle regulation, DNA repair, transcription, and endocytosis. This is because ubiquitin can alter the activity of its target in a variety of ways, from targeting it to the proteasome for degradation to alter its localization or enzymatic activity. We focus on the role of this pathway in two important cellular processes: Protein Quality Control and Host-Pathogen interactions.

 

Protein Quality Control

Despite the aid of chaperones, a significant fraction of newly synthesized proteins ends up misfolded. Cells evolved protein quality control systems to ensure that these potentially toxic species are detected and eliminated. The best characterized of this mechanism is the ER-associated protein degradation (ERAD), which takes care of membrane and secretory proteins that are misfolded in the endoplasmic reticulum (ER). We are interested to investigate how proteins misfold? How are misfolded proteins identified, translocated and ubiquitinated during ERAD.

 

Host-Pathogen Interactions

Viruses hijack the host machinery to their own advantage. During infection, several host defense mechanisms are destabilized by the virus using the ubiquitin-proteasome pathway. We study the interactions between viral factors and host proteins to understand this process.  We regularly use NMR spectroscopy to study protein structure and dynamics. In addition, we employ various other biophysical, biochemical and computational tools.

 

Positions: We are actively looking for postdocs with a Phd in protein-chemistry/protein-Xray-crystallography/protein-NMR. Please apply with a detailed CV to rana@ncbs.res.in. Your CV should reflect your expertise and research interest.

 

Recent Publications

Surana P#, Gowda CM#, Tripathi V, Broday L, Das R., (2017) Structural and functional analysis of SMO-1, the SUMO homolog in Caenorhabditis elegans, PLoS One. 12(10):e0186622. #Equal Contribution

Nandwani N#, Surana P#, Udgaonkar JB*, Das R*, Gosavi S.*, (2017) Amino-acid composition after loop deletion drives domain swapping, Protein Sci. 26(10):1994-2002. #Equal Contribution, *Corresponding authors.

Amanullah A, Mishra R, Upadhyay A, Reddy PP, Das R, Mishra A., (2017), Indomethacin Elicits Proteasomal Dysfunctions Develops Apoptosis Through Mitochondrial Abnormalities, J Cell Physiol., doi: 10.1002/jcp.26081.

Sengupta I, Bhate S, Das R*, Udgaonkar J*, (2017), Salt-binding induced oligomerization of the mouse proin protein monitored by real time NMR, J. Mol. Biol., 429(12): 1852-1872. *Corresponding authors.

Chakrabarti KS, Li J, Das R*, Byrd RA*, (2017), Conformational dynamics and allostery in E2:E3 interactions driving ubiquitination: Ube2g2 and gp78, Structure, 25(5):794-805. *Corresponding authors.

Positions:

Students interested in Phd are requested to apply through the NCBS-PhD program. There are no summer/winter positions available.