Light controls stamen elongation via cryptochromes, phytochromes and COP1 through HY5 and HYH. (13th April 2020)

• Record Type: Journal Article
• Authors: Marzi, Davide; Brunetti, Patrizia; Mele, Giovanni; Napoli, Nadia; Calò, Lorenzo; Spaziani, Erica; Matsui, Minami; De Panfilis, Simone; Costantino, Paolo; Serino, Giovanna; Cardarelli, Maura
• Is Part Of: Plant journal. Volume 103:Number 1(2020)
• Page Start: 379
• Page End: 394
• Publication Date: 2020-04-13
• Subjects: plant reproduction -- light signaling -- stamen -- auxin -- COP1 -- HY5 -- IAA19 -- phytochrome -- cryptochrome -- Arabidopsis thaliana; Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.14736
• Languages: English
• ISSNs: 0960-7412

Abstract

SUMMARY: In Arabidopsis, stamen elongation, which ensures male fertility, is controlled by the auxin response factor ARF8, which regulates the expression of the auxin repressor IAA19 . Here, we uncover a role for light in controlling stamen elongation. By an extensive genetic and molecular analysis we show that the repressor of light signaling COP1, through its targets HY5 and HYH, controls stamen elongation, and that HY5 – oppositely to ARF8 – directly represses the expression of IAA19 in stamens. In addition, we show that in closed flower buds, when light is shielded by sepals and petals, the blue light receptors CRY1/CRY2 repress stamen elongation. Coherently, at flower disclosure and in subsequent stages, stamen elongation is repressed by the red and far‐red light receptors PHYA/PHYB. In conclusion, different light qualities – sequentially perceived by specific photoreceptors – and the downstream COP1–HY5/HYH module finely tune auxin‐induced stamen elongation and thus male fertility. Significance Statement: In Arabidopsis auxin‐induced stamen elongation is essential for optimizing the transfer of pollen grains onto the pistil to allow successful fertilization. Here we show that different light qualities, via the conserved COP1–HY5/HYH module, finely tune auxin‐induced stamen elongation and thus male fertility.