fairfolio
Saved Projects

Investigating the Genes and Biochemical Pathway Responsible for Caffeine Production in Ilex vomitoria (Yaupon Holly)

ISEF · 2025 Plant Sciences Fourth Award

Tong, Claire, Yao, Janelle, Goel, Aanya · Kalamazoo Area Mathematics and Science Center

Is this your project?

Overview

Coffee and tea are among the world's most popular drinks, containing large quantities of caffeine, a central nervous system stimulant. Many plants have been shown to produce caffeine by using three genes either labeled caffeine synthase (CS) or xanthine methyltransferase (XMT). One plant that produces caffeine is Ilex vomitoria (Yaupon Holly), one of the only two caffeine-producing plants in North America. It is closely related to Ilex paraguariensis (Yerba Mate), the only other known Ilex species capable of producing caffeine. We investigated three hypotheses: (1) we tested the presence of caffeine synthase type genes in Ilex vomitoria, (2) we tested whether the genes responsible for caffeine synthesis in Ilex vomitoria and Ilex paraguariensis were closely related, and (3) we tested for similarities in the biochemical pathways for caffeine production in the two species. To investigate these hypotheses, we first conducted transcriptome sequencing. Then, we identified caffeine synthase genes that were present in the Ilex vomitoria RNA sequence, and there was a clear lack of XMT genes. To amplify our three candidate genes, we conducted Reverse Transcriptase-Polymerase Chain Reaction. Afterwards, these genes were cloned and transformed into Escherichia coli. We used an enzyme assay to test these enzymes from our cultures, creating a phylogenetic tree to analyze this data. The tree indicated that IvRT1 is closely related to IpCS3 and that IvRT8 is closely related to IpCS2. However, there was no sequence in the Ilex vomitoria transcriptome that closely matches IpCS1. Lastly, our enzyme assay showed that IvRT8 methylates 3-methylxanthine to produce theobromine, as expected. This result is similar to the known biochemical pathway of Ilex paraguariensis.

Working on something like this? See what's been done and what's still open.

Awards (1)

Competition history

Resources

Related projects

Closest projects by meaning, across every fair and year in the corpus.

Browse more like this

Report a problem

Source: Regeneron International Science and Engineering Fair

Save projects to your library

Sign in with Google to keep track of projects you find interesting, organized into folders. An account also raises your daily allowance for “Has this been done?”, and lets you create a key for the MCP server with a much higher limit than anonymous use. Browsing stays public.

Continue with Google