Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus
Variation in thermal tolerance plays a key role in determining the biogeographic distribution of organisms. Consequently, identifying the mechanistic basis for thermal tolerance is necessary for understanding not only current species range limits but also the capacity for range limits to shift in re...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2019-03-01
|
| Series: | Frontiers in Physiology |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/article/10.3389/fphys.2019.00213/full |
| _version_ | 1811197657119457280 |
|---|---|
| author | Alice E. Harada Timothy M. Healy Ronald S. Burton |
| author_facet | Alice E. Harada Timothy M. Healy Ronald S. Burton |
| author_sort | Alice E. Harada |
| collection | DOAJ |
| description | Variation in thermal tolerance plays a key role in determining the biogeographic distribution of organisms. Consequently, identifying the mechanistic basis for thermal tolerance is necessary for understanding not only current species range limits but also the capacity for range limits to shift in response to climate change. Although variation in mitochondrial function likely contributes to variation in thermal tolerance, the extent to which mitochondrial function underlies local thermal adaptation is not fully understood. In the current study, we examine variation in thermal tolerance and mitochondrial function among three populations of the intertidal copepod Tigriopus californicus found across a latitudinal thermal gradient along the coast of California, USA. We tested (1) acute thermal tolerance using survivorship and knockdown assays, (2) chronic thermal tolerance using survivorship of nauplii and developmental rate, and (3) mitochondrial performance at a range of temperatures using ATP synthesis fueled by complexes I, II, and I&II, as well as respiration of permeabilized fibers. We find evidence for latitudinal thermal adaptation: the southernmost San Diego population outperforms the northernmost Santa Cruz in measures of survivorship, knockdown temperature, and ATP synthesis rates during acute thermal exposures. However, under a chronic thermal regime, survivorship and developmental rate are more similar in the southernmost and northernmost population than in the mid-range population (Abalone Cove). Though this pattern is unexpected, it aligns well with population-specific rates of ATP synthesis at these chronic temperatures. Combined with the tight correlation of ATP synthesis decline and knockdown temperature, these data suggest a role for mitochondria in setting thermal range limits and indicate that divergence in mitochondrial function is likely a component of adaptation across latitudinal thermal gradients. |
| first_indexed | 2024-04-12T01:17:31Z |
| format | Article |
| id | doaj.art-4f4a8c438da7429ba53d8d3d411dad8f |
| institution | Directory Open Access Journal |
| issn | 1664-042X |
| language | English |
| last_indexed | 2024-04-12T01:17:31Z |
| publishDate | 2019-03-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Physiology |
| spelling | doaj.art-4f4a8c438da7429ba53d8d3d411dad8f2022-12-22T03:53:53ZengFrontiers Media S.A.Frontiers in Physiology1664-042X2019-03-011010.3389/fphys.2019.00213425510Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicusAlice E. HaradaTimothy M. HealyRonald S. BurtonVariation in thermal tolerance plays a key role in determining the biogeographic distribution of organisms. Consequently, identifying the mechanistic basis for thermal tolerance is necessary for understanding not only current species range limits but also the capacity for range limits to shift in response to climate change. Although variation in mitochondrial function likely contributes to variation in thermal tolerance, the extent to which mitochondrial function underlies local thermal adaptation is not fully understood. In the current study, we examine variation in thermal tolerance and mitochondrial function among three populations of the intertidal copepod Tigriopus californicus found across a latitudinal thermal gradient along the coast of California, USA. We tested (1) acute thermal tolerance using survivorship and knockdown assays, (2) chronic thermal tolerance using survivorship of nauplii and developmental rate, and (3) mitochondrial performance at a range of temperatures using ATP synthesis fueled by complexes I, II, and I&II, as well as respiration of permeabilized fibers. We find evidence for latitudinal thermal adaptation: the southernmost San Diego population outperforms the northernmost Santa Cruz in measures of survivorship, knockdown temperature, and ATP synthesis rates during acute thermal exposures. However, under a chronic thermal regime, survivorship and developmental rate are more similar in the southernmost and northernmost population than in the mid-range population (Abalone Cove). Though this pattern is unexpected, it aligns well with population-specific rates of ATP synthesis at these chronic temperatures. Combined with the tight correlation of ATP synthesis decline and knockdown temperature, these data suggest a role for mitochondria in setting thermal range limits and indicate that divergence in mitochondrial function is likely a component of adaptation across latitudinal thermal gradients.https://www.frontiersin.org/article/10.3389/fphys.2019.00213/fulllocal adaptationATP synthesisintertidaltimescaleectothermcopepod |
| spellingShingle | Alice E. Harada Timothy M. Healy Ronald S. Burton Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus Frontiers in Physiology local adaptation ATP synthesis intertidal timescale ectotherm copepod |
| title | Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus |
| title_full | Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus |
| title_fullStr | Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus |
| title_full_unstemmed | Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus |
| title_short | Variation in Thermal Tolerance and Its Relationship to Mitochondrial Function Across Populations of Tigriopus californicus |
| title_sort | variation in thermal tolerance and its relationship to mitochondrial function across populations of tigriopus californicus |
| topic | local adaptation ATP synthesis intertidal timescale ectotherm copepod |
| url | https://www.frontiersin.org/article/10.3389/fphys.2019.00213/full |
| work_keys_str_mv | AT aliceeharada variationinthermaltoleranceanditsrelationshiptomitochondrialfunctionacrosspopulationsoftigriopuscalifornicus AT timothymhealy variationinthermaltoleranceanditsrelationshiptomitochondrialfunctionacrosspopulationsoftigriopuscalifornicus AT ronaldsburton variationinthermaltoleranceanditsrelationshiptomitochondrialfunctionacrosspopulationsoftigriopuscalifornicus |