Abstract The genusMyotisis one of the largest clades of bats, and exhibits some of the most extreme variation in lifespans among mammals alongside unique adaptations to viral tolerance and immune defense. To study the evolution of longevity-associated traits and infectious disease, we generated near-complete genome assemblies and cell lines for 8 closely related species ofMyotis. Using genome-wide screens of positive selection, analyses of structural variation, and functional experiments in primary cell lines, we identify new patterns of adaptation contributing to longevity, cancer resistance, and viral interactions in bats. We find thatMyotisbats have some of the most significant variation in cancer risk across mammals and demonstrate a unique DNA damage response in primary cells of the long-livedM. lucifugus. We also find evidence of abundant adaptation in response to DNA viruses - but not RNA viruses - inMyotisand other bats in sharp contrast with other mammals, potentially contributing to the role of bats as reservoirs of zoonoses. Together, our results demonstrate how genomics and primary cells derived from diverse taxa uncover the molecular bases of extreme adaptations in non-model organisms.
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Enhanced DNA Damage Response in a Clade of Long-Lived Bats Resolved Using Chromosome-Length Genome Assemblies
Lifespan is one of the most variable traits across the entire tree of life, and especially in mammals. Differences in lifespans between closely-related species provides a promising avenue for discovering novel pro-longevity pathways using evolutionary techniques. Previous studies focused on the evolution of longevity-associated traits, such as DNA damage response, have been hampered by a combination of low-quality genomes, low-phylogenetic coverage, or long evolutionary times, all of which can negatively affect their power to detect genes associated with longevity. In order to comprehensively study the evolution of aging and aging-associated traits in bats, we generated chromosome-level reference genomes and primary cell line libraries from a 10-million-year-old clade of 9 California Myotis species spanning a 3-fold range of lifespans. Increases and decreases in longevity independent of body size have evolved multiple times in this clade, providing a dynamic range which can be studied through functional genomics. Leveraging both genomes and cell lines, we identify several pathways specifically associated with longevity, in addition to other longevity-associated traits such as DNA repair and immunity; and show that these changes are associated with cellular resistance to various forms of chemically-induced DNA damage. These pathways represent new targets for exploration using primary cell cultures, and contribute to our understanding of how both agonistic and antagonistic pleiotropy play a role in the evolution of longevity. NSF PRFB 2109915 NIH 5R35GM142916-03. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
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- Award ID(s):
- 2010884
- PAR ID:
- 10519562
- Publisher / Repository:
- Int. Union Physiol. Sci./Am. Physiol. Soc.
- Date Published:
- Journal Name:
- Physiology
- Volume:
- 39
- Issue:
- S1
- ISSN:
- 1548-9213
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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