Brassinosteroid receptors reveal conserved features of exon-embedded gene regulation

Denia-Mondejar, R.; Brunot-Garau, P.; Ma, X.; Serrano-Mislata, A.; Dolores Gomez, M.; Latrasse, D.; Benhamed, M.; Hardtke, C. S.; Blanco-Tourinan, N.

doi:10.64898/2026.09.21.753065

bioRxiv · 10.64898/2026.09.21.753065

Brassinosteroid receptors reveal conserved features of exon-embedded gene regulation

Denia-Mondejar, R.·Brunot-Garau, P.·Ma, X.·Serrano-Mislata, A.·Dolores Gomez, M.·Latrasse, D.·Benhamed, M.·Hardtke, C. S.·Blanco-Tourinan, N.

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Abstract

Precise quantitative and spatial control of plant gene expression is typically attributed to cis-regulatory elements in promoters and other non-coding sequences. The extent to which exon-encoded regulatory information shapes plant gene expression and how remains unclear. Here we used BRASSINOSTEROID INSENSITIVE 1 (BRI1) as a model locus and found that it contains an exonic enhancer (EE), which is essential to establish the spatial BRI1 expression pattern. Its disruption restricts BRI1 expression and impairs BRI1-dependent root growth, linking exon-encoded regulatory information and development. The BRI1 EE acts in concert with its promoter, and related receptor kinase genes likewise harbor regulatory information within their coding sequences. Genome-wide surveys show that candidate EEs are associated with highly connected chromatin interaction networks and transcriptionally active loci. Moreover, species comparisons suggest that common features of exon-encoded regulatory information extend across diverse plant lineages. Thus, exon-encoded regulatory information is a vital component of plant gene regulation.

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Denia-Mondejar, R., Brunot-Garau, P., Ma, X., Serrano-Mislata, A., Dolores Gomez, M., Latrasse, D., Benhamed, M., Hardtke, C. S., Blanco-Tourinan, N.. 2026-09-23. Brassinosteroid receptors reveal conserved features of exon-embedded gene regulation. https://doi.org/10.64898/2026.09.21.753065

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