Two rice caryopsis-specific transcription factors, ONAC127 and ONAC129, have
been found to respond to heat stress and are involved in the caryopsis
filling process. To know more about their functions, the researchers
obtained CRISPR-Cas9 induced mutants and overexpression lines of them. This
led them to the discovery that both knock-out and overexpression plants
exhibited incomplete filling and shrunken caryopses, which was more severe
when exposed to heat stress. Further analyses also showed that ONAC127 and
ONAC129 are mainly involved in stimulus response, cell wall construction,
and nutrient transport.



The findings may indicate that ONAC127 and ONAC129 regulate caryopsis
filling through sugar transportation and abiotic stress responses. Overall,
the study demonstrates the transcriptional regulatory networks involving
ONAC127 and ONAC129, which synchronizes several pathways to control
caryopsis development and heat stress response during the rice filling
stage.



[www.biorxiv.org]