Investigating the transcriptional regulation of auxin biosynthesis in Arabidopsis embryo

Survival of flowering plants is determined by the proper production of seed, whose shape and size are defined by the development of an embryo. Such mature embryo mimics the body pattern of the new plant that will develop after germination. Auxin is a key regulator of various aspects of plant development, including embryo morphogenesis.

Cellular auxin gradients, maintained by auxin production along with signalling and transport, are essential for proper embryo development.

The embryonic local auxin biosynthesis appears spatiotemporally controlled, necessitating the presence of regulatory networks.

Also, it became evident that auxin plays a critical role as an integrator of environmental cues, notably high temperatures, known to impair seed production.

Thus, I aim at deciphering the molecular and genetic mechanisms behind the spatiotemporal regulation of auxin biosynthetic genes during embryo development, and how this regulatory network is impacted by heat stress.

In the proposed work, I will functionally dissect the contribution of AGL transcription factors, identified in a yeast one-hybrid screen as binding to auxin biosynthetic promoters, to the direct regulation of auxin biosynthetic pathways using multidisciplinary approaches such as genetics, metabolomics, and molecular biology.

Further, I will investigate whether high temperatures impact this regulation, notably at epigenetic levels.

Overall, the proposed work would serve as an excellent foundation to dissect the mechanisms responsible for local auxin biosynthesis during embryo development, which would pave the way to devise strategies for mitigating the effects of climate warming on seed and plant morphogenesis.