Unconventional Protein Secretion in Plants.
Unconventional protein secretion (UPS) describes secretion pathways that bypass one or several of the canonical secretion pit-stops on the way to the plasma membrane, and/or involve the secretion of leaderless proteins. So far, alternatives to conventional secretion were primarily observed and studied in yeast and animal cells. The sessile lifestyle of plants brings with it unique restraints on how they adapt to adverse conditions and environmental challenges. Recently, attention towards unconventional secretion pathways in plant cells has substantially increased, with the large number of leaderless proteins identified through proteomic studies. While UPS pathways in plants are certainly not yet exhaustively researched, an emerging notion is that induction of UPS pathways is correlated with pathogenesis and stress responses. Given the multitude UPS events observed, comprehensively organizing the routes proteins take to the apoplast in defined UPS categories is challenging. With the establishment of a larger collection of studied plant proteins taking these UPS pathways, a clearer picture of endomembrane trafficking as a whole will emerge. There are several novel enabling technologies, such as vesicle proteomics and chemical genomics, with great potential for dissecting secretion pathways, providing information about the cargo that travels along them and the conditions that induce them.
Department of Plant Sciences, University of California, Asmundson Hall, One Shields Avenue, Davis, CA, 95616, USA.
Destiny J
DJ
Davis
Center for Organelle Biogenesis and Function, School of Life Sciences, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
Byung-Ho
BH
Kang
Department of Plant Sciences, University of California, Asmundson Hall, One Shields Avenue, Davis, CA, 95616, USA.
Angelo S
AS
Heringer
Department of Plant Sciences, University of California, Asmundson Hall, One Shields Avenue, Davis, CA, 95616, USA. tewilkop@ucdavis.edu.
Thomas E
TE
Wilkop
Department of Plant Sciences, University of California, Asmundson Hall, One Shields Avenue, Davis, CA, 95616, USA. gdrakakaki@ucdavis.edu.
Georgia
G
Drakakaki
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005089:Exocytosis; D055354:Exosomes / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D008561:Membrane Fusion; D015388:Organelles / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D021381:Protein Transport; D040901:Proteomics; D055571:Secretory Pathway; D022142:Secretory Vesicles / Q000378:metabolism; D015003:Yeasts / Q000378:metabolism
D010940:Plant Proteins
Chemical genomics; Endomembrane trafficking; Leaderless proteins; Protein secretion; Signal peptide; Unconventional protein secretion (UPS); Vesicle proteomics