Coordination of shoot apical meristem shape and identity by APETALA2 during floral transition in Arabidopsis

• Published in: Nature communications Vol. 15; no. 1; pp. 6930 - 16
• Main Authors: Bertran Garcia de Olalla, Enric, Cerise, Martina, Rodríguez-Maroto, Gabriel, Casanova-Ferrer, Pau, Vayssières, Alice, Severing, Edouard, López Sampere, Yaiza, Wang, Kang, Schäfer, Sabine, Formosa-Jordan, Pau, Coupland, George
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 13-08-2024; Nature Publishing Group; Nature Portfolio
• Subjects: 14/19; 14/35; 14/63; 38/39; 38/91; 631/449/1659; 631/449/2653/2657; 631/449/2679/2681; Arabidopsis; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Flowering; Flowers; Flowers - genetics; Flowers - growth & development; Flowers - metabolism; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Gene silencing; Height; Homeodomain Proteins - genetics; Homeodomain Proteins - metabolism; Humanities and Social Sciences; MADS Domain Proteins - genetics; MADS Domain Proteins - metabolism; Meristem - genetics; Meristem - growth & development; Meristem - metabolism; Meristems; multidisciplinary; Plants (botany); Plants, Genetically Modified; Science; Science (multidisciplinary); Shoots; Synchronism; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-51341-6

Plants flower in response to environmental signals. These signals change the shape and developmental identity of the shoot apical meristem (SAM), causing it to form flowers and inflorescences. We show that the increases in SAM width and height during floral transition correlate with changes in size of the central zone (CZ), defined by
CLAVATA3
expression, and involve a transient increase in the height of the organizing center (OC), defined by
WUSCHEL
expression. The APETALA2 (AP2) transcription factor is required for the rapid increases in SAM height and width, by maintaining the width of the OC and increasing the height and width of the CZ. AP2 expression is repressed in the SAM at the end of floral transition, and extending the duration of its expression increases SAM width. Transcriptional repression by SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) represents one of the mechanisms reducing AP2 expression during floral transition. Moreover, AP2 represses
SOC1
transcription, and we find that reciprocal repression of SOC1 and AP2 contributes to synchronizing precise changes in meristem shape with floral transition.
Bertran Garcia de Olalla, Cerise and colleagues discovered that the transcription factor APETALA2 has a dual role at the shoot tip of Arabidopsis, where it both mediates changes in the timing of flowering and in the morphology of the shoot apex.