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Abstract BackgroundLife cycle evolution includes ecological transitions and shifts in the timing of somatic and reproductive development (heterochrony). However, heterochronic changes can be tissue‐specific, ultimately leading to the differential diversification of traits. Salamanders exhibit alternative life cycle polymorphisms involving either an aquatic to terrestrial metamorphosis (biphasic) or retention of aquatic larval traits into adulthood (paedomorphic). In this study, we used gene expression and histology to evaluate how life cycle evolution impacts temporal reproductive patterns in males of a polymorphic salamander. ResultsWe found that heterochrony shifts the distribution of androgen signaling in the integument, which is correlated with significant differences in seasonal reproductive gland development and pheromone gene expression. In the testes, androgen receptor (ar) expression does not significantly vary between morphs or across seasons. We found significant differences in the onset of spermatogenesis, but by peak breeding season the testes were the same with respect to both histology and gene expression. ConclusionThis study provides an example of how seasonal heterochronic shifts in tissue‐specificargene expression can disparately impact seasonal development and expression patterns across tissues, providing a potential mechanism for differential diversification of reproductive traits.
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This content will become publicly available on August 20, 2026
Expanded application to plant reproductive tissues of a branched DNA probe‐based in situ hybridization method
Abstract PremiseDetecting clear tissue‐ and organ‐specific patterns of gene expression is key to understanding the genetic mechanisms that control plant development. In situ hybridization (ISH) of mRNA is one of the most precise, yet most challenging approaches to gene expression assays. Methods and ResultsDetection of histone H4 expression in reproductive tissues ofMimulus lewisii, a model angiosperm, was optimized using the RNAscope ISH assay. The optimized protocol was used to detect histone H4 expression in reproductive tissues of two gymnosperm species,Taxodium distichumandJuniperus virginiana, without further need for species‐specific optimization. Additionally, the optimized protocol was used to detect expression ofCYCLOIDEAtranscription factors inM. lewisiireproductive tissues without further optimization and with results similar to those previously reported. ConclusionsThe RNAscope assay can quickly and sensitively generate high‐quality ISH results in reproductive tissues across a breadth of plant species.
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- Award ID(s):
- 2421327
- PAR ID:
- 10630005
- Publisher / Repository:
- Wiley Publishing
- Date Published:
- Journal Name:
- Applications in Plant Sciences
- ISSN:
- 2168-0450
- Page Range / eLocation ID:
- 10.1002/aps3.70020
- Subject(s) / Keyword(s):
- branched DNA probes CYCLOIDEA histone H4 inflorescence in situ hybridization reproductive cone RNAscope Z-probe
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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