Agriculture Reference
In-Depth Information
basic monopartite NLS signals (NLS1, NLS2) and one NES motif are present in
p62 (Pankiv et al.
2010
), however the role of p62 in the nucleus is unclear. It is
speculated that, since in the nucleus in contrast to the cytoplasm, only proteasomal
degradation system takes place, p62 may act as a polyubiquitin targeting factor
carrying substrates to a nuclear pool of proteasomes. It could be also involved in the
transport of other proteins or it could act as a sensor of nuclear and cytosolic
proteotoxic stress. The role of NLS and NES motifs and the significance of nuclear
localization have not yet been investigated in NBR1-like proteins.
Conclusions and Future Perspectives
Within this chapter multiple reasons to continue studies on autophagy in
plants have been highlighted. Autophagy plays a protective role during
nutrient starvation (and other environmental stresses) by enhancing the
recycling of unwanted cellular materials. The process is evolutionarily con-
served. In animals, induction of autophagy results in extension of the life span
(Madeo et al.
2010
; Rubinsztein et al.
2011
), while defective autophagy has
been related to cancer, various neurodegenerative and immune-related dis-
eases (Todde et al.
2009
). Various genetic, pharmacological or nutritional
approaches designed to improve autophagy in human may be a future strategy
of choice to avoid or delay aging-associated pathologies. Such potential
therapies still need further extensive investigation. Considering the strong
conservation of the process and the participating proteins, studies on
autophagy in plants can give clues to this area of medical research by
providing inexpensive testing models for novel drugs and treatments. Addi-
tionally, in plants, autophagy is involved in regulation of the lifespan (Minina
et al.
2013
).
Sufficient knowledge of these mechanisms may allow for controlled
genetic or molecular manipulations of plant metabolism. All modifications
leading to moderate up-regulation of autophagy may have a positive impact
on plant biomass and crop yield. Studies on regulation of the specificity of
autophagy and its role in maintaining proteostasis (protein homeostasis), as
well as overall homeostasis, have become very active areas of research.
Nevertheless many important questions remain unanswered. The problems
still to be elucidated include the regulation of the specificity of the autophagy
process and its role in maintaining proteostasis (protein homeostasis), as well
as overall homeostasis in plants and other living organisms,
including
humans.
Acknowledgements M.C.-R. was supported by the Marie Curie Initial Training Network
BIONUT (project No. 264296). K. Z-R is supported by National Science Centre, Poland (project
No. 201/05/N/NZ1/00699). Research in A.S. lab is also supported by the Polish Ministry of
Science and Higher Education (project No. W16/7.PR/2011).
