The Relationship between AGAMOUS and Cytokinin Signaling in the Establishment of Carpeloid Features

• Main Authors: Andrea Gómez-Felipe, Daniel Kierzkowski, Stefan de Folter
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: Plants
• Subjects: AGAMOUS; cytokinin signaling; carpel; gynoecium; transcription factors; CRC
• Online Access: https://www.mdpi.com/2223-7747/10/5/827

Gynoecium development is dependent on gene regulation and hormonal pathway interactions. The phytohormones auxin and cytokinin are involved in many developmental programs, where cytokinin is normally important for cell division and meristem activity, while auxin induces cell differentiation and organ initiation in the shoot. The MADS-box transcription factor AGAMOUS (AG) is important for the development of the reproductive structures of the flower. Here, we focus on the relationship between AG and cytokinin in <i>Arabidopsis thaliana</i>, and use the weak <i>ag-12</i> and the strong <i>ag-1</i> allele. We found that cytokinin induces carpeloid features in an AG-dependent manner and the expression of the transcription factors <i>CRC</i>, <i>SHP2</i>, and <i>SPT</i> that are involved in carpel development. AG is important for gynoecium development, and contributes to regulating, or else directly regulates <i>CRC</i>, <i>SHP2</i>, and <i>SPT</i>. All four genes respond to either reduced or induced cytokinin signaling and have the potential to be regulated by cytokinin via the type-B ARR proteins. We generated a model of a gene regulatory network, where cytokinin signaling is mainly upstream and in parallel with AG activity.