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Title: OsSWEET11b , a potential sixth leaf blight susceptibility gene involved in sugar transport‐dependent male fertility

SWEETs play important roles in intercellular sugar transport. Induction of SWEET sugar transporters by Transcription Activator‐Like effectors (TALe) ofXanthomonasssp. is key for virulence in rice, cassava and cotton.

We identified OsSWEET11b with roles in male fertility and potential bacterial blight (BB) susceptibility in rice. While singleossweet11aor11bmutants were fertile, double mutants were sterile. As clade III SWEETs can transport gibberellin (GA), a key hormone for spikelet fertility, sterility and BB susceptibility might be explained by GA transport deficiencies. However, in contrast with the Arabidopsis homologues, OsSWEET11b did not mediate detectable GA transport. Fertility and susceptibility therefore are likely to depend on sucrose transport activity.

Ectopic induction ofOsSWEET11bby designer TALe enabled TALe‐freeXanthomonas oryzaepv.oryzae(Xoo) to cause disease, identifyingOsSWEET11bas a potential BB susceptibility gene and demonstrating that the induction of host sucrose uniporter activity is key to virulence ofXoo. Notably, only three of six clade III SWEETs are targeted by knownXoostrains from Asia and Africa.

The identification of OsSWEET11b is relevant for fertility and for protecting rice against emergingXoostrains that targetOsSWEET11b.

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Author(s) / Creator(s):
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Publisher / Repository:
Date Published:
Journal Name:
New Phytologist
Page Range / eLocation ID:
p. 975-989
Medium: X
Sponsoring Org:
National Science Foundation
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