Caylyn Railey
Caylyn Railey
Faculty Advisor: Wojtek Pawlowsk
Year: 2019
Mentor: Duoduo Wang

Characterizing the Role of AM1 and MET1 in Early Meiosis via Virus Induced Gene Silencing

Understanding the constituents and the mechanisms of meiosis in plants could reveal major implications regarding plant development. The majority of genetic diversity is generated via recombination during Meiosis I. Interestingly, recombination events are not evenly distributed among the genome and repair is not particularly efficient. Previous research has shown that these discrepancies can be attributed to location on the chromosome or chromatin structure and availability. Previous studies have shown that crossovers tend to occur in hot spots that experience low level of DNA methylation. When these genetic areas are observed in Tomato or Arabidopsis, these areas are saturated with epigenetically modified heterochromatin by DNA and histone methylation. However, how DNA methylation influences the meiotic recombination landscape in crops with large and complex genomes has not been fully investigated yet due to the challenges of creating a viable stable mutant.

In this study, we leveraged virus induced gene silencing method to investigate if silencing Ameiotic1 (Am1) and Methtyltransferase1 (Met1) in maize will affect meiotic recombination in maize. Previous study has revealed that AM1 was involved in a series of meiotic events such as chromosome structure, telomere behavior, recombination, and meiotic cytoskeleton arrangement. Met1 is responsible for DNA methylation in CG context in maize and the function of met1 involved in meiosis is unknown. We used a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV) to silence AM1 and Met1 in maize and results showed that FoMV could infect maize leaf tissue effectively. Additionally, using Alexander’s Staining we found that in AM1 silenced maize, total pollen number was decreased and had a greater relative abundance of non-viable pollen.

 

My Experience

I have always been interested in plant science, but I never realized the breadth of the field until this summer. From the weekly seminars to the benchwork in the lab, I experienced the true extent of plant science and inquiry. The variety of my daily work and ability to tackle projects from new perspectives provided an environment that cultivated my skills as a researcher. All of of the guidance and support of my lab allowed me to be curious and learn new techniques. BTI and Cornell gave me the ability to experience an environment that constantly pushed me to think deeper. This exposure to plant science has only solidified my aspirations of obtaining a PhD. and becoming an advocate for global and human health.

Beyond the work in the lab and greenhouse, the ability to surround myself with like-minded people was extremely rewarding. It was so nice to be able to connect with peers that were just as excited about research as I was. I not only built a sound network of connections, but I have created new and lasting friendships.