Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
, 8 (11)

Autophagy and Nutrients Management in Plants

Affiliations
Review

Autophagy and Nutrients Management in Plants

Qinwu Chen et al. Cells.

Abstract

Nutrient recycling and mobilization from organ to organ all along the plant lifespan is essential for plant survival under changing environments. Nutrient remobilization to the seeds is also essential for good seed production. In this review, we summarize the recent advances made to understand how plants manage nutrient remobilization from senescing organs to sink tissues and what is the contribution of autophagy in this process. Plant engineering manipulating autophagy for better yield and plant tolerance to stresses will be presented.

Keywords: iron; leaf senescence; nitrogen remobilization; nitrogen use efficiency; plant proteases; zinc.

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Schematic representation of macro-autophagy and micro-autophagy pathways in plants. Nutrient availability controls the TOR (target of rapamycin) kinase activity that, in turn, regulates post-transcriptionally maro-autophagy through the phosphorylation of ATG1 and ATG13 (autophagy proteins 1 and 13). After nucleation of the pre-autophagosome structures, the autophagy ATG9, ATG18, and ATG2 proteins (in blue) are involved in the expansion of the membrane of the autophagosome. Several autophagy (ATG) proteins (in orange) involved in the conjugation of ATG8 to phosphatidyl-ethanolamine facilitate ATG8 anchorage to the membrane of the pre-autophagosome and per se autophagosome formation and enclosure. The ATG8-interacting motifs facilitate the capture of cargoes to be driven to the central vacuole for degradation. Micro-autophagy consists of the invagination of the tonoplast and participates in the formation of anthocyanin vacuole inclusions (AVI).
Figure 2
Figure 2
Schematic representation of the different steps of nutrient recycling in plant cells. Chloroplast material and unwanted cytoplasmic material are driven to the central vacuole for degradation through the macro-autophagy pathway. Once delivered to the vacuole lumen, autophagic bodies (inner membrane of autophagosome and cargoes) are degraded by the resident proteases and hydrolases. The nutrients released are exported to the cytosol and using transporters or canals. Once inside the cytosol, nutrients are either used for cell metabolism or released out of the cell for source to sink translocation. Interconversions of amino-acids occur in the cytosol to produce the glutamine and asparagine forms that are preferentially used for long-distance transport in the phloem. Many black boxes remain to be explored, especially regarding the docking of autophagosomes to the tonoplast and the transport of nutrients out of the vacuole and further out of the cell (question marks).
Figure 3
Figure 3
Modification of macro- and micronutrient fluxes in autophagy mutants and overexpressors in Arabidopsis. The green and blue arrows indicate the lack (as percentages) of micro and macro-nutrient allocation to the seeds in the atg5 knock out (atg5-KO) mutant relative to wild type. The red arrows indicate the extra nitrogen remobilization measured in ATG8 Arabidopsis overexpressors, by comparison, to the control line under plethoric nitrate conditions.

Similar articles

See all similar articles

Cited by 2 articles

References

    1. Dikic I. Proteasomal and autophagic degradation systems. Annu. Rev. Biochem. 2017;86:193–224. doi: 10.1146/annurev-biochem-061516-044908. - DOI - PubMed
    1. Masclaux-Daubresse C., Chen Q., Havé M. Regulation of nutrient recycling via autophagy. Curr. Opin. Plant. Biol. 2017;39:8–17. doi: 10.1016/j.pbi.2017.05.001. - DOI - PubMed
    1. Hershko A., Ciechanover A. The ubiquitin system. Annu. Rev. Biochem. 1998;67:425–479. doi: 10.1146/annurev.biochem.67.1.425. - DOI - PubMed
    1. Li F., Vierstra R.D. Autophagy: A multifaceted intracellular system for bulk and selective recycling. Trends Plant. Sci. 2012;17:526–537. doi: 10.1016/j.tplants.2012.05.006. - DOI - PubMed
    1. Pourcel L., Irani N.G., Lu Y., Riedl K., Schwartz S., Grotewold E. The Formation of anthocyanic vacuolar inclusions in Arabidopsis thaliana and implications for the sequestration of anthocyanin pigments. Mol. Plant. 2010;3:78–90. doi: 10.1093/mp/ssp071. - DOI - PMC - PubMed

Publication types

Feedback