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Title: Rhomboid-mediated cleavage of the immune receptor XA21 protects grain set and male fertility in rice
To maintain growth and to successfully reproduce, organisms must protect key functions in specific tissues, particularly when countering pathogen invasion using internal defensive proteins that may disrupt their own developmental processes. The rice immune receptor XA21 confers race-specific resistance againstXanthomonas oryzaepv.oryzae, which causes the deadly disease bacterial leaf blight. Here, we demonstrate that XA21 is cleaved by the rhomboid-like protease OsRBL3b, likely within its transmembrane domain.OsRBL3bmRNA transcripts are preferentially expressed in rice spikelets. Rice plants expressingXa21but lacking a functionalOsRBL3bdisplayed impaired anther dehiscence and pollen viability, resulting in male sterility and yield reduction with high levels of XA21 protein present in spikelets during anthesis. In leaves,osrbl3bmutants expressing XA21 had normal levels of this resistance protein and disease immunity. This balance between reproduction and disease resistance through the specific expression of a rhomboid protease may be key to limiting the detrimental effects of an active immune response and may be useful in future for genetic improvement of crops.  more » « less
Award ID(s):
1748105
PAR ID:
10613889
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
National Academy of Sciences USA
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
122
Issue:
22
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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