Inbreeding-related trade-offs in stress resistance in the ant
            Formica exsecta

Inbred individuals and populations are predicted to suffer from inbreeding depression, especially in times of stress. Under natural conditions, organisms are exposed to more than one stressor at any one time, highlighting the importance of stress resistance traits. We studied how inbreeding- and immunity-related traits are correlated under different dietary conditions in the ant Formica exsecta . Its natural diet varies in the amount and nature of plant secondary compounds and the level of free radicals, all of which require detoxification to maintain organismal homeostasis. We found that inbreeding decreased general antibacterial activity under dietary stress, suggesting inbreeding-related physiological trade-offs.

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Hepatic gene expression in herbivores on diets with natural and novel plant secondary compounds

Physiological Genomics ◽

10.1152/physiolgenomics.00033.2013 ◽

2013 ◽

Vol 45 (17) ◽

pp. 774-785 ◽

Cited By ~ 4

Author(s):

Elodie Magnanou ◽

Jael R. Malenke ◽

M. Denise Dearing

Keyword(s):

Gene Expression ◽

Great Basin ◽

Large Scale ◽

Physiological Stress ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Secondary Compounds ◽

Plant Secondary Compounds ◽

Secondary Chemistry ◽

Natural Diet

Herbivores are predicted to evolve appropriate mechanisms to process the plant secondary compounds (PSCs) in their diet, and these mechanisms are likely specific to particular suites of PSCs. Changes in diet composition over evolutionary time should select for appropriate alterations in metabolism of the more recent dietary components. We investigated differences in gene expression profiles in the liver with respect to prior ecological and evolutionary experience with PSCs in the desert woodrat, Neotoma lepida. This woodrat species has populations in the Mojave Desert that have switched from feeding on juniper to feeding on creosote at the end of the Holocene as well as populations in the Great Basin Desert that still feed on the ancestral diet of juniper and are naïve to creosote. Juniper and creosote have notable differences in secondary chemistry. Woodrats from the Mojave and Great Basin Deserts were subjected to a fully crossed feeding trial on diets of juniper and creosote after which their livers were analyzed for gene expression. Hybridization of hepatic mRNAs to laboratory rat microarrays resulted in a total of 20,031 genes that met quality control standards. We analyzed differences in large-scale patterns of liver gene expression with respect to GO term enrichment. Diet had a larger effect on gene expression than population membership. However, woodrats with no prior evolutionary experience to the diet upregulated a greater proportion of genes indicative of physiological stress compared with those on their natural diet. This pattern may be the result of a naïve animal's attempting to mitigate physiological damage caused by novel PSCs.

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Enterotypes of the Gut Microbial Community and Their Response to Plant Secondary Compounds in Plateau Pikas

Microorganisms ◽

10.3390/microorganisms8091311 ◽

2020 ◽

Vol 8 (9) ◽

pp. 1311

Author(s):

Chao Fan ◽

Liangzhi Zhang ◽

Haibo Fu ◽

Chuanfa Liu ◽

Wenjing Li ◽

...

Keyword(s):

Microbial Community ◽

Microbial Diversity ◽

Secondary Compounds ◽

Short Chain Fatty Acids ◽

Plant Secondary Compounds ◽

Plateau Pika ◽

Natural Diet ◽

Rdna Sequencing ◽

Plant Secondary Compound ◽

Dominant Bacteria

Animal gut microbiomes can be clustered into “enterotypes” characterized by an abundance of signature genera. The characteristic determinants, stability, and resilience of these community clusters remain poorly understood. We used plateau pika (Ochotona curzoniae) as a model and identified three enterotypes by 16S rDNA sequencing. Among the top 15 genera, 13 showed significantly different levels of abundance between the enterotypes combined with different microbial functions and distinct fecal short-chain fatty acids. We monitored changes in the microbial community associated with the transfer of plateau pikas from field to laboratory and observed that feeding them a single diet reduced microbial diversity, resulting in a single enterotype with an altered composition of the dominant bacteria. However, microbial diversity, an abundance of some changed dominant genera, and enterotypes were partially restored after adding swainsonine (a plant secondary compound found in the natural diet of plateau pikas) to the feed. These results provide strong evidence that gut microbial diversity and enterotypes are directly related to specific diet, thereby indicating that the formation of different enterotypes can help animals adapt to complex food conditions. Additionally, natural plant secondary compounds can maintain dominant bacteria and inter-individual differences of gut microbiota and promote the resilience of enterotypes in small herbivorous mammals.

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