Avian lung single-cell atlas elucidates evolutionary divergence in endothermic respiration

2026/03/19 by Yan Hao, Xiang Zhou, Qingshuo Zhao +10 · 1 voice · 1 citation
Biochemistry, Genetics and Molecular Biology · Medicine · #Congenital heart defects research #Neonatal Respiratory Health Research #Single-cell and spatial transcriptomics

paper · doi:10.1093/molbev/msag072

openalex publication_date 2026/03/19 · openalex created_date 2026/05/06 · openalex updated_date 2026/07/31

Abstract

The evolution of distinct lung architectures in birds (tubular air capillaries) and mammals (alveoli) represents a classic example of convergent evolution, yet their cellular differences remain poorly characterized. We present the comparative single-cell atlas of avian and mammalian lungs, revealing four key findings. First, we discover a persistent hybrid cell population (AT1/AT2) in neonatal and adult birds that disappears postnatally in mice, uncovering distinct strategies for lung maintenance. Second, cross-species comparisons highlight striking divergence in alveolar cell types, reflecting specialized adaptations to different respiratory demands. Third, avian lungs show unique molecular signatures in proliferation and saccular development pathways, potentially explaining their superior respiratory efficiency. Fourth, our viral receptor analysis uncovered differential ACE2 (SARS-CoV-2 receptor) expression but conserved EGFR (influenza A receptor), suggesting species-specific disease vulnerabilities. This work provides unprecedented insights into the evolutionary and developmental mechanisms shaping lung diversity in endotherms, with implications for respiratory biology, regenerative medicine, and zoonotic disease research.

Citations

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Cited by

• Highlight: comparative single-cell analysis reveals how birds and mammals build distinct lung architectures

Discussions

• Hao et al. compared single-cell atlas of avian and mammalian lungs, showing distinct developmental strategies for lung maintenance and lung cell types, and distinct patterns of coronavirus and influen [bsky, 3 points, 1 comments]

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