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  • AtSTP8, an endoplasmic reticulum‐localised monosaccharide transporter from Arabidopsis, is recruited to the extrahaustorial membrane during powdery mildew infection
Title: AtSTP8, an endoplasmic reticulum‐localised monosaccharide transporter from Arabidopsis, is recruited to the extrahaustorial membrane during powdery mildew infection
Summary Biotrophic pathogens are believed to strategically manipulate sugar transport in host cells to enhance their access to carbohydrates. However, mechanisms of sugar translocation from host cells to biotrophic fungi such as powdery mildew across the plant–haustorium interface remain poorly understood.To investigate this question, systematic subcellular localisation analysis was performed for all the 14 members of the monosaccharide sugar transporter protein (STP) family inArabidopsis thaliana. The best candidate AtSTP8 was further characterised for its transport properties inSaccharomyces cerevisiaeand potential role in powdery mildew infection by gene ablation and overexpression in Arabidopsis.Our results showed that AtSTP8 was mainly localised to the endoplasmic reticulum (ER) and appeared to be recruited to the host‐derived extrahaustorial membrane (EHM) induced by powdery mildew. Functional complementation assays inS. cerevisiaesuggested that AtSTP8 can transport a broad spectrum of hexose substrates. Moreover, transgenic Arabidopsis plants overexpressingAtSTP8showed increased hexose concentration in leaf tissues and enhanced susceptibility to powdery mildew.Our data suggested that the ER‐localised sugar transporter AtSTP8 may be recruited to the EHM where it may be involved in sugar acquisition by haustoria of powdery mildew from host cells in Arabidopsis.  more » « less
Award ID(s):
1901566
PAR ID:
10450773
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
230
Issue:
6
ISSN:
0028-646X
Page Range / eLocation ID:
p. 2404-2419
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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