Valerie Chen
Year: 2017

“Understanding the Function of MBP3 gene in Tomato Fruit Development and Ripening”


Project Summary

The cultivated tomato fruit, Solanum lycopersicum, is an important component of the human diet. By studying genes that are involved in tomato fruit ripening, scientists can manipulate fruit development to create better products with increased nutrition, quality and taste. The Sl-MBP3 gene is a transcription factor gene that affects the development of tomato fruit tissue. Downregulation of this gene through RNA interference (RNAi) causes a full flesh phenotype (tomato fruit without jelly), whereas in tomatoes where this gene is expressed the fruit contains jelly in which seeds are encased.

The purpose of this project is to look for possible differences in cell size and structure between the Sl-MBP3 RNAi full flesh tomato fruit and the normal tomato with jelly (control). In order to do this, we prepared tomato fruit tissues so the cells could be clearly observed under a microscope. For preparation, tissue samples from various stages of both the mutant and control tomatoes were fixed in a formalin solution and embedded in paraffin. They were cut into sections with a microtome and stained with toluidine blue. Lastly, they were examined under a microscope. We showed that in early stages of fruit development,

MBP3-RNAi fruit and control fruit have similar cell structure. However, differences in cell adhesion and consequently the differences in cell shape were observed at the mature green stage when fruit starts gelatinizing. This observation suggests a possible function of Sl-MBP3 gene in regulating some of the cell wall enzymes that that play a key role in gelatinization of tomato fruit during ripening.

My Experience:

My time at BTI this summer has been a valuable learning experience. Before this internship, I had never worked in a lab before, but now I can say I truly enjoyed it. The Giovannoni lab is full of amazing people that contributed to the overall friendly atmosphere of the lab. Throughout these past six weeks, I’ve learned how to work in a professional setting, new lab techniques, such as how to prepare slides in order to study cells under a microscope, and how to conduct scientific research. I’ve discovered that plant biology research is fascinating, as well as crucial for better understanding of the environment and improving human health. I would like to thank my mentor, Julia Vrebalov. I thoroughly enjoyed working with her and learning from her these past weeks. She guided me through my research, yet she allowed me to work independently as well so I could learn and grow as a student. I am very thankful for the internship for giving me this incredible opportunity.