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ABSTRACT There is increasing evidence for the co‐occurrence of adaptive within‐generation (WGP) and transgenerational (TGP) plasticity and the ecological scenarios driving both types of plasticity. However, some aspects of their transcriptional mechanisms, such as the role of alternative splicing and the consequences of parental acclimation across life stages, have remained elusive. We explore these fundamental questions by considering the desert endemicDrosophila mojavensisfor which prior evidence indicates adaptive thermal acclimation within and across generations. We implement a full factorial design to estimate genome‐wide patterns of differential gene expression (DE) and alternative splicing (AS) in response to acclimation treatments performed in the parental and offspring generations, as well as considering larval and adult stages. Our results demonstrate that mechanisms of alternative splicing represent a substantial difference between WGP and TGP. These mechanisms contribute substantially to transcriptional plasticity within generations but not across generations. We found a great number of genes associated with transcriptional TGP, which is exclusive to larval stages and not adult samples. Finally, we provide evidence demonstrating opposing transcriptional trajectories in differential gene expression between WGP and TGP. Thus, parental acclimation appears to up‐regulate genes that are down‐regulated during offspring acclimation. This pattern suggests a possible hypothesis for the mechanisms explaining the compensatory effect of parental acclimation in the offspring generation.
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Increased Breeding Frequency Mitigates Inbreeding Depression in Peromyscus in Captivity
ABSTRACT Increased parental relatedness occurs in small wild populations and in closed colonies in captivity and reduces offspring fitness. A closed colony ofPeromyscus maniculatusis maintained as genetically diverse stock at the Peromyscus Genetic Stock Center since 1963. Breeding records are available for all the years of breeding in captivity, which allows evaluation of the breeding performance since the inception of the stock. Kinship calculations showed that increased parental relatedness results in offspring loss, which is consistent with the operation of inbreeding depression and is common in small populations, both wild and captive. Nonetheless, an adaptive response was recorded that mitigated the adverse consequences of inbreeding and contributed to the long‐term stability of the colony: When parental relatedness increased, more offspring were produced, resulting in the overall number of viable offspring being unaffected. The underlying mechanism involved adjustments in the interval for mating between related parents, causing the production of more litters. These adaptive changes indicate that the harmful consequences of inbreeding may be partially relieved by mechanisms involving changes in the animals' reproductive strategy. The availability of the breeding records ofP. maniculatusenables the performance of additional studies asking different questions regarding the breeding dynamics of a closed colony under regulated conditions.
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- PAR ID:
- 10615745
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology and Evolution
- Volume:
- 15
- Issue:
- 7
- ISSN:
- 2045-7758
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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