TY - JOUR
T1 - A new genome allows the identification of genes associated with natural variation in aluminium tolerance in Brachiaria grasses
AU - Worthington, Margaret
AU - Perez, Juan
AU - Mussurova, Saule
AU - Silva-Cordoba, Alexander
AU - Castiblanco, Valheria
AU - Arango, Juan
AU - Jones, Charlotte
AU - Fernandez Fuentes, Narcis
AU - Skot, Leif
AU - Dyer, Sarah
AU - Tohme, Joe
AU - Di Palma, Federica
AU - Arango, Jacobo
AU - Armstead, Ian
AU - De Vega, Jose
N1 - This work was partially funded by a Biotechnology and Biology Sciences Research Council (BBSRC)’s Global Challenge Research Fund BB/P028098/1 and a BBSRC’s Newton Fund Postdoctoral Twinning Award BBS/OS/NW/000011.
PY - 2021/2/2
Y1 - 2021/2/2
N2 - Toxic concentrations of aluminium cations and low phosphorus availability are the main yield-limiting factors in acidic soils, which represent half of the potentially available arable land. Brachiaria grasses, which are commonly sown as forage in the tropics because of their resilience and low demand for nutrients, show greater tolerance to high concentrations of aluminium cations (Al3+) than most other grass crops. In this work, we explored the natural variation in tolerance to Al3+ between high and low tolerant Brachiaria species and characterized their transcriptional differences during stress. We identified three QTLs (quantitative trait loci) associated with root vigour during Al3+ stress in their hybrid progeny. By integrating these results with a new Brachiaria reference genome, we identified 30 genes putatively responsible for Al3+ tolerance in Brachiaria. We observed differential expression during stress of genes involved in RNA translation, response signalling, cell wall composition, and vesicle location homologous to aluminium-induced proteins involved in limiting uptake or localizing the toxin. However, there was limited regulation of malate transporters in Brachiaria, which suggests that exudation of organic acids and other external tolerance mechanisms, common in other grasses, might not be relevant in Brachiaria. The contrasting regulation of RNA translation and response signalling suggests that response timing is critical in high Al3+-tolerant Brachiaria.
AB - Toxic concentrations of aluminium cations and low phosphorus availability are the main yield-limiting factors in acidic soils, which represent half of the potentially available arable land. Brachiaria grasses, which are commonly sown as forage in the tropics because of their resilience and low demand for nutrients, show greater tolerance to high concentrations of aluminium cations (Al3+) than most other grass crops. In this work, we explored the natural variation in tolerance to Al3+ between high and low tolerant Brachiaria species and characterized their transcriptional differences during stress. We identified three QTLs (quantitative trait loci) associated with root vigour during Al3+ stress in their hybrid progeny. By integrating these results with a new Brachiaria reference genome, we identified 30 genes putatively responsible for Al3+ tolerance in Brachiaria. We observed differential expression during stress of genes involved in RNA translation, response signalling, cell wall composition, and vesicle location homologous to aluminium-induced proteins involved in limiting uptake or localizing the toxin. However, there was limited regulation of malate transporters in Brachiaria, which suggests that exudation of organic acids and other external tolerance mechanisms, common in other grasses, might not be relevant in Brachiaria. The contrasting regulation of RNA translation and response signalling suggests that response timing is critical in high Al3+-tolerant Brachiaria.
KW - Acid soils
KW - Brachiaria
KW - QTL mapping
KW - Urochloa
KW - aluminium tolerance
KW - differential expression
KW - genome assembly
KW - grass
UR - http://www.scopus.com/inward/record.url?scp=85101285086&partnerID=8YFLogxK
U2 - 10.1093/jxb/eraa469
DO - 10.1093/jxb/eraa469
M3 - Article
C2 - 33064149
SN - 0022-0957
VL - 72
SP - 302
EP - 319
JO - Journal of Experimental Botany
JF - Journal of Experimental Botany
IS - 2
ER -