Denisse Rojas working with Arabidopsis in Fischer Lab
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My name is Denisse Rojas. I am a fifth-year undergraduate student -- a double major in Integrative Biology and Sociology -- and I grew up in the San Francisco Bay Area. 

I became interested in research after taking Bio 1A, an introductory course, my junior year. I was fascinated by genetics. In particular, I was intrigued by the structure and function of DNA and how it was initially discovered.


I was in awe of the x-ray crystallography of DNA which displayed its marvelous helix structure; how a muscle cell and a skin cell could have an identical genetic constitution yet carry out entirely different functions; and learning how Watson and Crick used various clues to elucidate the structure of DNA was like watching a fast-paced detective movie. I wanted to solve biological mysteries like Watson and Crick. 


I have been a member of Dr. Robert Fischer's lab for a year and a half, and I've enjoyed being able to apply knowledge I've learned in my science classes to a real, hands-on project. What I enjoy the most about PMB is that it's small and personal. After years of taking classes with 200+ students, majoring in a very large department, and frankly being overwhelmed at times by the size of the student body on campus, it has been a relief having a small niche of my own in PMB. 


I've formed close relationships with members in my lab and I'm always happy to see familiar faces around Koshland Hall.


In April 2011, I was fortunate to receive the Robert and Colleen Haas Scholarship. The Haas Scholars Program was established to support undergraduate student researchers from any department to conduct an independent research project for one year. With assistance from this program, I am currently undertaking a research project alongside my wonderful graduate student mentor, Rie Uzawa.


The project, "A Novel Mechanism of Silencing Transposable Elements", aims to give insight to small RNA regulation of transposable elements in the egg cell. Transposable elements (TEs) pose a threat to genome integrity because of their mobile nature -- TEs can replicate and disrupt normal gene function and cell activity. TE activity is suppressed by small interfering RNAs (siRNAs) and this regulation is especially important in reproductive cells.


Previous studies in the male gametophyte infer that siRNAs produced in the supporting vegetative cell translocate to the sperm cell to help prevent TE mutagenic activity. The project I am working on aims to observe a similar phenomenon in the female gametophyte. The goal of my research is to test the idea that siRNAs move from the supporting central cell to the egg cell and silence TE expression and movement in the egg.


Applying for the Haas Scholarship was a difficult process, but very rewarding. Applicants are required to submit a research proposal, and I didn't know where to begin. I had not written one before or had even engaged in extensive scientific literature. Luckily I had a great deal of help from all my lab members, my mentor Dr. Fischer, and Leah Carroll, the Haas Scholarship Coordinator.


I would recommend prospective applicants start as soon as possible! I have thoroughly enjoyed my time in the scholarship program. Since the scholarship is awarded to students from a variety of disciplines, I have learned about research projects very different than my own. I'm grateful to have met other students who are passionate about their research and hope that their perseverance can rub off on me. I look forward to continuing my research project and in being involved in the Haas Scholars Program.