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Tightening the pores to unload the phloem


Root growth depends on the shoot-to-root transport of assimilates through the phloem, which is connected to the meristems by plasmodesmata pores. A PHLOEM UNLOADING MODULATOR is now identified to regulate plasmodesmata internal organisation, leading to pores that appear tighter but are more efficient for transport.

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Fig. 1: Type I and type II plasmodesmata differ in symplastic conductivity.


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Correspondence to Yoselin Benitez-Alfonso.

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Amsbury, S., Benitez-Alfonso, Y. Tightening the pores to unload the phloem. Nat. Plants 5, 561–562 (2019).

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