DECUSSATE network with flowering genes explains the variable effects of qDTY12.1 to rice yield under drought across genetic backgrounds

• Published in: The plant genome Vol. 15; no. 1; pp. e20168 - n/a
• Main Authors: Sanchez, Jacobo, Kaur, Pushpinder Pal, Pabuayon, Isaiah C. M., Karampudi, Naga Bhushana Rao, Kitazumi, Ai, Sandhu, Nitika, Catolos, Margaret, Kumar, Arvind, los Reyes, Benildo G.
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01.03.2022; Wiley
• Subjects: Agricultural production; Chromosomes; Cultivars; Cytokinins; Drought; Droughts; Fines & penalties; Flowering; Genes; Genetic Background; Genomes; Hypotheses; Oryza - genetics; Plant Leaves - genetics; Quantitative Trait Loci; Rain; Rice; Signal transduction; Transcription
• ISSN: 1940-3372; 1940-3372
• DOI: 10.1002/tpg2.20168

The impact of qDTY12.1 in maintaining yield under drought has not been consistent across genetic backgrounds. We hypothesized that synergism or antagonism with additive‐effect peripheral genes across the background genome either enhances or undermines its full potential. By modeling the transcriptional networks across sibling qDTY12.1‐introgression lines with contrasting yield under drought (LPB = low‐yield penalty; HPB = high‐yield penalty), the qDTY12.1‐encoded DECUSSATE gene (OsDEC) was revealed as the core of a synergy with other genes in the genetic background. OsDEC is expressed in flag leaves and induced by progressive drought at booting stage in LPB but not in HPB. The unique OsDEC signature in LPB is coordinated with 35 upstream and downstream peripheral genes involved in floral development through the cytokinin signaling pathway. Results support the differential network rewiring effects through genetic coupling–uncoupling between qDTY12.1 and other upstream and downstream peripheral genes across the distinct genetic backgrounds of LPB and HPB. The functional DEC‐network in LPB defines a mechanism for early flowering as a means for avoiding the drought‐induced depletion of photosynthate needed for reproductive growth. Its impact is likely through the timely establishment of stronger source‐sink dynamics that sustains a robust reproductive transition under drought. Core Ideas Optimal effect of qDTY12.1 on yield maintenance under drought is defined largely by its interaction with the genetic background. The qDTY12.1‐encoded DECUSSATE gene (OsDEC) is a putative regulator of flowering during drought through cytokinin signaling. OsDEC is the core of a drought response genetic network at reproductive transition, comprised of flowering‐associated genes from across the genome. Coupling of qDTY12.1‐encoded OsDEC allele with a battery of compatible peripheral flowering‐associated genes across the genome creates an optimal flowering response genetic network during drought. Optimal OsDEC network facilitates an earlier transition to flowering and efficiently channels photosynthates from the progressively depleting vegetative source to maintain the strength of reproductive sink.