Roshini graduated from the Madurai Kamaraj University in India. Results of her previous work were published in Journal of Bacteriology, November 2010, p. 6039-6044, Vol. 192, No. 22; Evidence that the supE44 Mutation of Escherichia coli Is an Amber Suppressor Allele of glnX and that It Also Suppresses Ochre and Opal Nonsense Mutations; B. Singaravelan, B. R. Roshini,, and M. Hussain Munavar

Since October 2010, she's been a member of the IGSDHD program. During the rotation period she worked at the laboratory of:

  • Prof. Karin Schnetz, project: "Characterization of YjjQ by identification of its target genes in Escherichia coli
  • Dr. Niels Gehring, project: "Studying mRNA export in mammalian cells”
  • Prof. Jürgen Dohmen, project: " Role of antizyme in ubiquitin-independent proteasomal degradation of ODC"

Since April 2011, she's been working on her PhD project in the group of Prof. Dohmen.

Project description

Polyamines are essential organic polycations which have been implicated in various cellular processes. Cellular polyamine concentrations are regulated mainly at the level of synthesis but also at the level of catabolism and export. Elevated cellular polyamine levels lead to the induction of antizyme translation by a highly conserved mechanism involving +1 ribosomal frameshifting. The antizyme targets ornithine decarboxylase (ODC), the rate limiting enzyme in polyamine biosynthesis for ubiquitin-independent degradation by the 26S proteasome. The N-terminal degron of ODC and the antizyme are essential for the effective degradation of ODC. Polyamines also regulate antizyme levels by blocking its ubiquitin-dependent protein degradation. In this study, the mechanisms of regulating polyamine levels by the antizyme are dissected