Maize field in Missouri, 2018, Margot Bezrutczyk
"Heritable...with its reams of field-trial data, represents a sort of Googlification of the breeding process, making it possible for breeders to search and explore the large number of possible genetic combinations for a given crop"
beneficial plant-microbe interactions
Illustration by Kent Leech
Our latest research from my team at JGI made the cover of Nature Plants!
We developed the first spatially-resolved single cell transcriptome of a plant-fungal interaction.
https://www.nature.com/articles/s41477-024-01666-3
Here's an interview about my work at the Joint Genome Institute with science comedian Brian Malowe:
An interview with Menaka Willhelm about my single-cell genomics work, for the Genome Insider podcast:
sugar transport in maize
Sugar is the currency of the biological world, and maize is grown primarily for the sugars (and other carbohydrates) in its kernels. We found evidence for a novel route that sugar takes on its way to the kernel from the leaf, and discovered several transport proteins necessary for this process.
Using single cell sequencing, we identified a subset of bundle sheath cells in the maize leaf:
We confirmed the localization key marker genes for this bundle sheath cell sub-type: ZmSWEET13a, SWEET13b, and SWEET13c. The mRNA transcripts from these genes were detected only in abaxial bundle sheath cells: likely a newly discovered subfunctionalization of this cell type.
We propose a novel route for sugar to enter phloem in the maize leaf minor veins (rank-2 intermediate veins), which are the most numerous and critical for sugar transport out of the leaf.
During this research we optimized a protocol for in situ hybridization in mature plant leaf tissue: https://doi.org/10.1016/j.xpro.2021.100398
Using a multiplexed CRISPR-Cas9-mediated knockout strategy, we confirmed that the bidirectional sucrose transporters SWEET13a, SWEET13b, and SWEET13c are critical for phloem loading in maize:
