Abstract:
:The coordinated redistribution of sugars from mature "source" leaves to developing "sink" leaves requires tight regulation of sugar transport between cells via plasmodesmata (PD). Although fundamental to plant physiology, the mechanisms that control PD transport and thereby support development of new leaves have remained elusive. From a forward genetic screen for altered PD transport, we discovered that the conserved eukaryotic glucose-TOR (TARGET OF RAPAMYCIN) metabolic signaling network restricts PD transport in leaves. Genetic approaches and chemical or physiological treatments to either promote or disrupt TOR activity demonstrate that glucose-activated TOR decreases PD transport in leaves. We further found that TOR is significantly more active in mature leaves photosynthesizing excess sugars than in young, growing leaves, and that this increase in TOR activity correlates with decreased rates of PD transport. We conclude that leaf cells regulate PD trafficking in response to changing carbohydrate availability monitored by the TOR pathway.
journal_name
Proc Natl Acad Sci U S Aauthors
Brunkard JO,Xu M,Scarpin MR,Chatterjee S,Shemyakina EA,Goodman HM,Zambryski Pdoi
10.1073/pnas.1919196117subject
Has Abstractpub_date
2020-03-03 00:00:00pages
5049-5058issue
9eissn
0027-8424issn
1091-6490pii
1919196117journal_volume
117pub_type
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