Stick insects (Phasmatodea) possess ancestral antimicrobial peptide genes lost by later insect lineages, revealing evolutionary plasticity in innate immunity across insects.
Ancestral genes preservedStick insects retain innate immunity genes that later insect lineages have lost
What the researchers found
Stick insects possess a unique AMP repertoire including ancestral innate immunity genes lost by later insect clades, revealed by immune challenge and transcriptomic analysis.
Why it matters
Understanding the evolutionary history of antimicrobial peptides across insects reveals how immunity diversifies and may uncover novel AMPs with unique antimicrobial properties.
The numbers in context
5 AMP families; 45 LPS-binding proteins; multiple novel cysteine-rich peptides identified
How the study worked
Immune challenge of Peruphasma schultei stick insects with microbial elicitor mixture. Transcriptomic analysis of the immune response to identify and characterize antimicrobial peptide genes.
Who was studied
Peruphasma schultei (stick insect species)
What this study cannot tell us
Single species studied. Functional characterization of identified AMPs not complete. Ecological significance of the unique repertoire unclear.
How to read the evidence
Preliminary — transcriptomic discovery study identifying novel AMP genes; functional characterization ongoing.
When this study was published
Published in 2020; insect antimicrobial peptide diversity continues to be explored as a source of novel compounds.
The bigger picture
Insects are the most species-rich animal group and represent a vast, largely untapped source of antimicrobial peptides. Studying ancestral lineages like stick insects reveals immunity genes that evolution explored but later discarded in other groups.
Questions still open
- Do any of the ancestral stick insect AMPs have therapeutic potential against human pathogens?
- Why were these immunity genes lost in later-evolving insect orders?
- Do other hemimetabolous insects retain similar ancestral AMP genes?
Common questions
Why study stick insect immunity?
Could insect peptides become human medicines?
Read the original research
The unique antimicrobial peptide repertoire of stick insects.
Developmental and comparative immunology, 103, 103471
Citation
Shelomi, Matan; Jacobs, Chris; Vilcinskas, Andreas; Vogel, Heiko. (2020). The unique antimicrobial peptide repertoire of stick insects.. Developmental and comparative immunology, 103, 103471. https://doi.org/10.1016/j.dci.2019.103471