REVIEW: Quality Control: Proteins and Organelles
V. N. Luzikov
Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State
University, Moscow, 119899 Russia; fax: (095) 939-3181; E-mail:
luzikov@genebee.msu.su
Received July 16, 2001
This review summarizes materials on the mechanisms of intracellular
degradation of proteins whose topogenesis is disturbed at one stage or
another. Chaperone and proteolytic systems involved in this process in
the endoplasmic reticulum, mitochondria, and chloroplasts of eucaryotic
cells as well as those in distinct subcellular compartments of
procaryotic cells are considered. The available data suggest that
living cells contain numerous systems keeping under control both
folding of newly synthesized and newly imported polypeptide chains and
their incorporation into heterooligomeric complexes. The point of view
is elaborated that organelle formation is controlled not only at the
level of individual protein molecules but also at the supermolecular
level when whole organelles incapable of carrying out their integral
key functions become targets for partial or total elimination. This
type of control is realized through an autophagic mechanism
involvinglysosomes/vacuoles.
KEY WORDS: protein, folding, oligomerization, glycosylation,
chaperones, proteases, quality control, ERAD, bacterial cells,
mitochondria, chloroplasts, peroxisomes, autophagy