A high-resolution gene expression map of the medial and lateral domains of the gynoecium of Arabidopsis

Abstract

Angiosperms are characterized by the formation of flowers, and in their inner floral whorl, one or various gynoecia are produced. These female reproductive structures are responsible for fruit and seed production, thus ensuring the reproductive competence of angiosperms. In Arabidopsis (Arabidopsis thaliana), the gynoecium is composed of two fused carpels with different tissues that need to develop and differentiate to form a mature gynoecium and thus the reproductive competence of Arabidopsis. For these reasons, they have become the object of study for floral and fruit development. However, due to the complexity of the gynoecium, specific spatio-temporal tissue expression patterns are still scarce. In this study, we used precise laser-assisted microdissection and high-throughput RNA sequencing to describe the transcriptional profiles of the medial and lateral domain tissues of the Arabidopsis gynoecium. We provide evidence that the method used is reliable and that, in addition to corroborating gene expression patterns of previously reported regulators of these tissues, we found genes whose expression dynamics point to being involved in cytokinin and auxin homeostasis and in cell cycle progression. Furthermore, based on differential gene expression analyses, we functionally characterized several genes and found that they are involved in gynoecium development. This resource is available via the Arabidopsis eFP browser and will serve the community in future studies on developmental and reproductive biology.

The role of D3-type cyclins is related to cytokinin and the bHLH transcription factor SPATULA in Arabidopsis gynoecium development

“…All this evidence suggests that CYCD3;2 and CYCD3;3 could play a role in the endocycle control and differentiation of the lateral and medial tissues in the gynoecium, but more studies are required. Note that no promoter CYCD3;1::GUS activity was detected in the gynoecium, but in the recently reported gynoecium expression map by Luna-García et al ( 2024 ), CYCD3;1 expression is detected in the medial and lateral domains of the gynoecium . This means that we must reserve strong conclusions on the lack of CYCD3;1 involvement during gynoecium development.…”