Related Experiment Video
Updated: Sep 9, 2025
09:13
Gene Expression Profiling of Infecting Microbes Using a Digital Bar-coding Platform
Published on: January 13, 2016
8.2K
Variation in Gene Expression Across Infection Status and Elevation in a Hawaiian Honeycreeper
Loren Cassin-Sackett1,2, Katherine M McClure1,3, Taylor E Callicrate1,4
1Center for Conservation Genomics, Smithsonian Conservation Biology Institute National Zoological Park Washington DC USA.
Ecology and Evolution
|September 5, 2025
Summary
Hawai
Area of Science:
- * Evolutionary biology
- * Ornithology
- * Immunology
Background:
- * Introduced pathogens, like the malaria parasite *Plasmodium relictum*, have caused severe declines in Hawaiian honeycreepers.
- * Avian malaria has led to extinctions and population crashes, particularly impacting Hawaiian honeycreepers.
- * Some Hawaiian honeycreeper populations, like the Hawai'i 'amakihi (*Chlorodrepanis virens*), exhibit varying immunity to avian malaria.
Purpose of the Study:
- * To investigate the genetic basis of adaptation to *Plasmodium relictum* in Hawaiian honeycreepers.
- * To identify genes and pathways involved in immunity to avian malaria in Hawai'i 'amakihi.
- * To explore potential trade-offs between immune response and environmental factors in different elevations.
Main Methods:
- * Transcriptome sequencing of low-elevation (immune) and high-elevation (non-immune) Hawai'i 'amakihi.
- * Differential gene expression analysis between infected/uninfected and low/high-elevation birds.
- * Gene set enrichment analysis to identify biological functions and pathways associated with immune response.
Main Results:
- * Infected birds showed significant differential gene expression related to immune response pathways.
- * Several top immune-related genes in Hawai'i 'amakihi were previously linked to malaria immunity and other infectious diseases.
- * A subset of genes, including those involved in metabolism and immune response, showed higher expression in high-elevation birds, suggesting potential trade-offs.
Conclusions:
- * A specific set of genes contributes to malaria immunity in Hawai'i 'amakihi.
- * Antagonistic interactions may exist between pathogen response and elevation-associated environmental factors.
- * Understanding these interactions is crucial for conserving Hawaiian honeycreepers in high-elevation refugia facing increasing malaria exposure.
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