Cynipid wasps reprogram host metabolism in developing galls

Northen Lab researchers Vlastimil Novak, Benjamin Bowen, Katherine Louie, and Trent Northen along with collaborators at University of California Berkeley, Joint BioEnergy Institute, LBNL, and Suranaree University of Technology co-authored the paper “Cynipid wasps systematically reprogram host metabolism and restructure cell walls in developing galls”. Galls are structures created by many insects to shelter their larva throughout development and allow them to feed on the host plant. This research provides insight to the underlying mechanism of gall development and highlights how cynipid wasps can alter the metabolite profile of host plants.

Based on existing literature, multiple separate mechanisms of gall induction are presumed to exist. The Northen lab’s efforts focused on creating metabolomic profiles of galled and ungalled leaf tissues to better understand the basis of these mechanisms. Comparing galled and ungalled tissues, there were very distinct metabolic differences in concentration of auxin and abscisic acid. However, we also observed a dramatic increase in the concentration of certain metabolites in morphologically different galled tissues, such as abscisic acid in urchin galls and hexose phosphates in cone galls. These metabolites are suggested to be key in achieving the specific morphology of each gall system, while those who did not change as drastically are suggested to be part of the shared induction mechanism. Our metabolomic results revealed increases in several compounds, such as gallotannins and some flavonoids, and decreases in acylglycerols and apocarotenoids within galled tissues. These findings helped us determine that each gall type is distinct from each other and leaf tissues.

Image: Venn diagram of the untargeted metabolomics mass features in galled and ungalled leaf tissues.

To explore more about these metabolomic findings as well as results from RNA sequencing, 3D light microscopy, and other key methods, read the full article here.

Kasey Markel, Vlastimil Novak, Benjamin P Bowen, Yang Tian, Yi-Chun Chen, Sasilada Sirirungruang, Andy Zhou, Katherine B Louie, Trent R Northen, Aymerick Eudes, Henrik V Scheller, Patrick M Shih, Cynipid wasps systematically reprogram host metabolism and restructure cell walls in developing galls, Plant Physiology, Volume 195, Issue 1, May 2024, Pages 698–712,