When do leaves commit to their phenotypic fate? Developmental point of no return on the early leaves from the det2-1 mutant of Arabidopsis thaliana

Leaves are extremely diverse in size and shape throughout the plant kingdom. Understanding processes that regulate how leaves grow and acquire their shape is essential for a better understanding of plant physiology and development. Here, we focus on, specifically in unveiling the presence of specific time points that can affect the whole morphology of an organ such as the leaf. The project emphasized in studying the developmental point of no return in the det2 (deetiolated2) mutant of Arabidopsis thaliana, which is characterized by its dwarfed, curly, and dark leaves. This phenotype can be reversed by supplementing the growth media with brassinosteroids, making it an excellent model for categorizing a developmental point of no return of the leaf. This was carried out by exposing det2 seedlings, and Col-0 as a control, to brassinosteroids on specific days in their development, while keeping a strict photographic record of the everyday growth. When comparing between both phenotypes and between plants not exposed to brassinosteroids, we detected that there was a gradual decline in the possibility of reversing the det2 leaf phenotype as the seedlings in later developmental stages were completely unaffected by the exogenous brassinosteroids. Our preliminary findings suggest that the presumed developmental point of no return in det2 leaves takes place in the early stages of development.

The internship has helped me settle the objectives I want to achieve through my career on both short term and long term, specially since I´m on the turning point of my career before going into research as a profession. The people I´ve met during the past months have opened my mind towards the conclusion of the inexistence of a linear pathway in research. Everyone has their own way of finding success through the things they are passionate about, understanding the human component in research is always essential. The experience I gained academically, professionally and personally during the summer will open doors to the future and thanks to that I´m more excited than ever when talking about the future. The work I did with Adrienne Roeder and Maura Zimmerman is invaluable in any term possible, their help was essential for sorting out the uncertainty of the future. I´m enthusiastic of the future towards grad school and the possibility of working in topics i´m really interested in researching in plant biology.