The boron efflux transporter ROTTEN EAR is required for maize inflorescence development and fertility

Chatterjee, M, Tabi Z, Galli M, Malcomber S, Buck A, Muszynski M, Gallavotti A.  2014.  

Journal:

Plant Cell

Issue Number:

26

Pages:

2962-2977

Abstract:

Although boron has a relatively low natural abundance, it is an essential plant micronutrient. Boron deficiencies cause major
crop losses in several areas of the world, affecting reproduction and yield in diverse plant species. Despite the importance of
boron in crop productivity, surprisingly little is known about its effects on developing reproductive organs. We isolated
a maize (Zea mays) mutant, called rotten ear (rte), that shows distinct defects in vegetative and reproductive development,
eventually causing widespread sterility in its inflorescences, the tassel and the ear. Positional cloning revealed that rte
encodes a membrane-localized boron efflux transporter, co-orthologous to the Arabidopsis thaliana BOR1 protein.
Depending on the availability of boron in the soil, rte plants show a wide range of phenotypic defects that can be fully
rescued by supplementing the soil with exogenous boric acid, indicating that rte is crucial for boron transport into aerial
tissues. rte is expressed in cells surrounding the xylem in both vegetative and reproductive tissues and is required for
meristem activity and organ development.We show that low boron supply to the inflorescences results in widespread defects in
cell and cell wall integrity, highlighting the structural importance of boron in the formation of fully fertile reproductive organs.

Related External URL:

http://www.plantcell.org/content/26/7/2962.full
Citation:
Chatterjee, M, Tabi Z, Galli M, Malcomber S, Buck A, Muszynski M, Gallavotti A.  2014.  The boron efflux transporter ROTTEN EAR is required for maize inflorescence development and fertility. Plant Cell. (26):2962-2977.