• Isaya, Grazia (PI)

Project: Research project

Project Details


Proteolytic processing of imported precursors is a crucial step in the
biogenesis of mitochondrial enzymes. It is our aim to study the
proteolytic removal of amino-terminal octapeptides from the mitochondrial
intermediate proteins. This cleavage event is unique to a sub-group of
mitochondrial enzymes and is specifically catalyzed by a mitochondrial
intermediate peptidase (MIP), likely to represent the first member of a
new family of endopeptidases. The main objective of this research
proposal is the characterization of MIP. The experiments proposed are
designed: 1) to determine the structural features of the MIP family; 2)
to establish the mechanism of action of MIP and define the elements that
direct recognition and cleavage of the mitochondrial intermediate
proteins; 3) to investigate the importance of MIP function for
mitochondrial homeostasis and cell viability. The experimental design
will require expression of the MIP gene in vitro and in vivo, and
reconstitution of MIP biogenesis and activity. The functional studies
will involve analysis of biological and biochemical aspects of MIP
inactivation in Saccharomyces cerevisiae. Specific techniques employed
will include: cloning, sequencing and manipulation of cDNA; genetic
manipulation in S. cerevisiae; isolation of mitochondria from rat liver
and S. cerevisiae; over-expression of recombinant proteins in E. coli;
PCR amplification; DNA and protein blotting. This study may provide
information at the level of a) components of the mitochondrial protein
import apparatus; b) novel mechanisms of endoproteolytic activity; c) new
pathways of mitochondrial disfunction.
Effective start/end date9/30/928/31/96


  • National Institutes of Health
  • National Institutes of Health: $183,951.00
  • National Institutes of Health: $172,854.00


  • Medicine(all)
  • Biochemistry, Genetics and Molecular Biology(all)


Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.