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Korabik AR, Winquist T, Grosholz ED, Hollarsmith JA. Examining the reproductive success of bull kelp (Nereocystis luetkeana, Phaeophyceae, Laminariales) in climate change conditions. JOURNAL OF PHYCOLOGY 2023; 59:989-1004. [PMID: 37540062 DOI: 10.1111/jpy.13368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/23/2023] [Accepted: 05/29/2023] [Indexed: 08/05/2023]
Abstract
Climate change is affecting marine ecosystems in many ways, including raising temperatures and leading to ocean acidification. From 2014 to 2016, an extensive marine heat wave extended along the west coast of North America and had devastating effects on numerous species, including bull kelp (Nereocystis luetkeana). Bull kelp is an important foundation species in coastal ecosystems and can be affected by marine heat waves and ocean acidification; however, the impacts have not been investigated on sensitive early life stages. To determine the effects of changing temperatures and carbonate levels on Northern California's bull kelp populations, we collected sporophylls from mature bull kelp individuals in Point Arena, CA. At the Bodega Marine Laboratory, we released spores from field-collected bull kelp, and cultured microscopic gametophytes in a common garden experiment with a fully factorial design crossing modern conditions (11.63 ± 0.54°C and pH 7.93 ± 0.26) with observed extreme climate conditions (15.56 ± 0.83°C and 7.64 ± 0.32 pH). Our results indicated that both increased temperature and decreased pH influenced growth and egg production of bull kelp microscopic stages. Increased temperature resulted in decreased gametophyte survival and offspring production. In contrast, decreased pH had less of an effect but resulted in increased gametophyte survival and offspring production. Additionally, increased temperature significantly impacted reproductive timing by causing female gametophytes to produce offspring earlier than under ambient temperature conditions. Our findings can inform better predictions of the impacts of climate change on coastal ecosystems and provide key insights into environmental dynamics regulating the bull kelp lifecycle.
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Affiliation(s)
- Angela R Korabik
- Department of Environmental Science and Policy, University of California Davis, Davis, California, USA
| | - Tallulah Winquist
- Department of Biology, San Diego State University, San Diego, California, USA
| | - Edwin D Grosholz
- Department of Environmental Science and Policy, University of California Davis, Davis, California, USA
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2
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Sunday JM, Howard E, Siedlecki S, Pilcher DJ, Deutsch C, MacCready P, Newton J, Klinger T. Biological sensitivities to high-resolution climate change projections in the California current marine ecosystem. GLOBAL CHANGE BIOLOGY 2022; 28:5726-5740. [PMID: 35899628 PMCID: PMC9542873 DOI: 10.1111/gcb.16317] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 05/03/2022] [Accepted: 05/21/2022] [Indexed: 06/01/2023]
Abstract
The California Current Marine Ecosystem is a highly productive system that exhibits strong natural variability and vulnerability to anthropogenic climate trends. Relating projections of ocean change to biological sensitivities requires detailed synthesis of experimental results. Here, we combine measured biological sensitivities with high-resolution climate projections of key variables (temperature, oxygen, and pCO2 ) to identify the direction, magnitude, and spatial distribution of organism-scale vulnerabilities to multiple axes of projected ocean change. Among 12 selected species of cultural and economic importance, we find that all are sensitive to projected changes in ocean conditions through responses that affect individual performance or population processes. Response indices were largest in the northern region and inner shelf. While performance traits generally increased with projected changes, fitness traits generally decreased, indicating that concurrent stresses can lead to fitness loss. For two species, combining sensitivities to temperature and oxygen changes through the Metabolic Index shows how aerobic habitat availability could be compressed under future conditions. Our results suggest substantial and specific ecological susceptibility in the next 80 years, including potential regional loss of canopy-forming kelp, changes in nearshore food webs caused by declining rates of survival among red urchins, Dungeness crab, and razor clams, and loss of aerobic habitat for anchovy and pink shrimp. We also highlight fillable gaps in knowledge, including specific physiological responses to stressors, variation in responses across life stages, and responses to multistressor combinations. These findings strengthen the case for filling information gaps with experiments focused on fitness-related responses and those that can be used to parameterize integrative physiological models, and suggest that the CCME is susceptible to substantial changes to ecosystem structure and function within this century.
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Affiliation(s)
| | - Evan Howard
- Department of GeosciencesPrinceton UniversityPrincetonNew JerseyUSA
| | - Samantha Siedlecki
- Department of Marine SciencesUniversity of ConnecticutGrotonConnecticutUSA
| | - Darren J. Pilcher
- Cooperative Institute for Climate, Ocean, and Ecosystem StudiesUniversity of WashingtonSeattleWashingtonUSA
| | - Curtis Deutsch
- Department of GeosciencesPrinceton UniversityPrincetonNew JerseyUSA
- High Meadows Environmental InstitutePrinceton UniversityPrincetonNew JerseyUSA
| | - Parker MacCready
- School of OceanographyUniversity of WashingtonSeattleWashingtonUSA
| | - Jan Newton
- Applied Physics Laboratory, University of WashingtonSeattleWashingtonUSA
| | - Terrie Klinger
- School of Marine and Environmental AffairsUniversity of WashingtonSeattleWashingtonUSA
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3
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Randell Z, Kenner M, Tomoleoni J, Yee J, Novak M. Kelp-forest dynamics controlled by substrate complexity. Proc Natl Acad Sci U S A 2022; 119:e2103483119. [PMID: 35181602 PMCID: PMC8872774 DOI: 10.1073/pnas.2103483119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 01/04/2022] [Indexed: 11/18/2022] Open
Abstract
The factors that determine why ecosystems exhibit abrupt shifts in state are of paramount importance for management, conservation, and restoration efforts. Kelp forests are emblematic of such abruptly shifting ecosystems, transitioning from kelp-dominated to urchin-dominated states around the world with increasing frequency, yet the underlying processes and mechanisms that control their dynamics remain unclear. Here, we analyze four decades of data from biannual monitoring around San Nicolas Island, CA, to show that substrate complexity controls both the number of possible (alternative) states and the velocity with which shifts between states occur. The superposition of community dynamics with reconstructions of system stability landscapes reveals that shifts between alternative states at low-complexity sites reflect abrupt, high-velocity events initiated by pulse perturbations that rapidly propel species across dynamically unstable state-space. In contrast, high-complexity sites exhibit a single state of resilient kelp-urchin coexistence. Our analyses suggest that substrate complexity influences both top-down and bottom-up regulatory processes in kelp forests, highlight its influence on kelp-forest stability at both large (island-wide) and small (<10 m) spatial scales, and could be valuable for holistic kelp-forest management.
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Affiliation(s)
- Zachary Randell
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331;
| | - Michael Kenner
- US Geological Survey, Western Ecological Research Center, Santa Cruz, CA 95060
| | - Joseph Tomoleoni
- US Geological Survey, Western Ecological Research Center, Santa Cruz, CA 95060
| | - Julie Yee
- US Geological Survey, Western Ecological Research Center, Santa Cruz, CA 95060
| | - Mark Novak
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331
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4
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Hodin J, Ferner MC, Gaylord B. Choosing the right home: settlement responses by larvae of six sea urchin species align with hydrodynamic traits of their contrasting adult habitats. Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlz149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Ocean organisms as diverse as seaweeds and sea cucumbers exhibit life cycles in which dispersal occurs primarily via microscopic larvae or spores, with adults exhibiting limited or even no dispersal. In benthic animals, the larval stage concludes with irreversible settlement into the benthos. The decision of where and when to settle is thus one of substantial import. Prior work has shown that settlement in two shoreline echinoids (a sea urchin and a sand dollar) is unexpectedly sensitive to an environmental feature (intense fluid turbulence) that can be considered as a signal to larvae of their arrival in the neighbourhood of the hydrodynamically energetic habitats in which these taxa live as adults. Here, we used a comparative approach to explore the evolution of turbulence responsiveness in late-stage echinoid larvae. We examined three pairs of closely related sea urchins that differ in the energetic exposure of their adult habitats and found that larval responsiveness to turbulence was more pronounced in urchins that settle in more hydrodynamically exposed locations. These results raise the possibility that evolutionary differences in larval responsiveness to environmental indicators of appropriate adult habitat might reinforce or even provide a mechanism for vicariance in the ocean.
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Affiliation(s)
- Jason Hodin
- Friday Harbor Laboratories, University of Washington, Friday Harbor, WA, USA
| | - Matthew C Ferner
- Estuary & Ocean Science Center, San Francisco State University, Tiburon, CA, USA
| | - Brian Gaylord
- Bodega Marine Laboratory, University of California at Davis, Bodega Bay, CA, USA
- Department of Evolution and Ecology, University of California at Davis, Davis, CA, USA
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5
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Rogers-Bennett L, Catton CA. Marine heat wave and multiple stressors tip bull kelp forest to sea urchin barrens. Sci Rep 2019; 9:15050. [PMID: 31636286 PMCID: PMC6803666 DOI: 10.1038/s41598-019-51114-y] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 09/23/2019] [Indexed: 11/09/2022] Open
Abstract
Extreme climatic events have recently impacted marine ecosystems around the world, including foundation species such as corals and kelps. Here, we describe the rapid climate-driven catastrophic shift in 2014 from a previously robust kelp forest to unproductive large scale urchin barrens in northern California. Bull kelp canopy was reduced by >90% along more than 350 km of coastline. Twenty years of kelp ecosystem surveys reveal the timing and magnitude of events, including mass mortalities of sea stars (2013-), intense ocean warming (2014-2017), and sea urchin barrens (2015-). Multiple stressors led to the unprecedented and long-lasting decline of the kelp forest. Kelp deforestation triggered mass (80%) abalone mortality (2017) resulting in the closure in 2018 of the recreational abalone fishery worth an estimated $44 M and the collapse of the north coast commercial red sea urchin fishery (2015-) worth $3 M. Key questions remain such as the relative roles of ocean warming and sea star disease in the massive purple sea urchin population increase. Science and policy will need to partner to better understand drivers, build climate-resilient fisheries and kelp forest recovery strategies in order to restore essential kelp forest ecosystem services.
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Affiliation(s)
- L Rogers-Bennett
- Coastal Marine Science Institute, Karen C. Drayer Wildlife Health Center, University of California, Davis, and California Department of Fish and Wildlife, Bodega Marine Laboratory 2099 Westside Rd., Bodega Bay, CA, 94923-0247, USA.
| | - C A Catton
- Coastal Marine Science Institute, Karen C. Drayer Wildlife Health Center, University of California, Davis, and California Department of Fish and Wildlife, Bodega Marine Laboratory 2099 Westside Rd., Bodega Bay, CA, 94923-0247, USA
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6
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Wong JM, Gaitán-Espitia JD, Hofmann GE. Transcriptional profiles of early stage red sea urchins (Mesocentrotus franciscanus) reveal differential regulation of gene expression across development. Mar Genomics 2019; 48:100692. [PMID: 31227413 DOI: 10.1016/j.margen.2019.05.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/28/2019] [Accepted: 05/29/2019] [Indexed: 12/17/2022]
Abstract
The red sea urchin, Mesocentrotus franciscanus, is an ecologically important kelp forest species that also serves as a valuable fisheries resource. In this study, we have assembled and annotated a developmental transcriptome for M. franciscanus that represents eggs and six stages of early development (8- to 16-cell, morula, hatched blastula, early gastrula, prism and early pluteus). Characterization of the transcriptome revealed distinct patterns of gene expression that corresponded to major developmental and morphological processes. In addition, the period during which maternally-controlled transcription was terminated and the zygotic genome was activated, the maternal-to-zygotic transition (MZT), was found to begin during early cleavage and persist through the hatched blastula stage, an observation that is similar to the timing of the MZT in other sea urchin species. The presented developmental transcriptome will serve as a useful resource for investigating, in both an ecological and fisheries context, how the early developmental stages of this species respond to environmental stressors.
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Affiliation(s)
- Juliet M Wong
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Juan D Gaitán-Espitia
- The Swire Institute of Marine Science, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong Special Administrative Region.
| | - Gretchen E Hofmann
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
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7
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Sato KN, Powell J, Rudie D, Levin LA. Evaluating the promise and pitfalls of a potential climate change-tolerant sea urchin fishery in southern California. ICES JOURNAL OF MARINE SCIENCE : JOURNAL DU CONSEIL 2018; 75:1029-1041. [PMID: 29881244 PMCID: PMC5972446 DOI: 10.1093/icesjms/fsx225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 06/08/2023]
Abstract
Marine fishery stakeholders are beginning to consider and implement adaptation strategies in the face of growing consumer demand and potential deleterious climate change impacts such as ocean warming, ocean acidification, and deoxygenation. This study investigates the potential for development of a novel climate change-tolerant sea urchin fishery in southern California based on Strongylocentrotus fragilis (pink sea urchin), a deep-sea species whose peak density was found to coincide with a current trap-based spot prawn fishery (Pandalus platyceros) in the 200-300-m depth range. Here we outline potential criteria for a climate change-tolerant fishery by examining the distribution, life-history attributes, and marketable qualities of S. fragilis in southern California. We provide evidence of seasonality of gonad production and demonstrate that peak gonad production occurs in the winter season. S. fragilis likely spawns in the spring season as evidenced by consistent minimum gonad indices in the spring/summer seasons across 4 years of sampling (2012-2016). The resiliency of S. fragilis to predicted future increases in acidity and decreases in oxygen was supported by high species abundance, albeit reduced relative growth rate estimates at water depths (485-510 m) subject to low oxygen (11.7-16.9 µmol kg-1) and pHTotal (<7.44), which may provide assurances to stakeholders and managers regarding the suitability of this species for commercial exploitation. Some food quality properties of the S. fragilis roe (e.g. colour, texture) were comparable with those of the commercially exploited shallow-water red sea urchin (Mesocentrotus franciscanus), while other qualities (e.g. 80% reduced gonad size by weight) limit the potential future marketability of S. fragilis. This case study highlights the potential future challenges and drawbacks of climate-tolerant fishery development in an attempt to inform future urchin fishery stakeholders.
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Affiliation(s)
- Kirk N Sato
- Marine Biophysics Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0218, USA
| | - Jackson Powell
- Florida State University, 319 Stadium Drive, Tallahassee, FL 32306, USA
| | - Dave Rudie
- Catalina Offshore Products Seafood Incorporated, 5202 Lovelock Street, San Diego, CA 92110, USA
| | - Lisa A Levin
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0218, USA
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8
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Pespeni MH, Chan F, Menge BA, Palumbi SR. Signs of adaptation to local pH conditions across an environmental mosaic in the California Current Ecosystem. Integr Comp Biol 2013; 53:857-70. [PMID: 23980118 DOI: 10.1093/icb/ict094] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Little is known about the potential for rapid evolution in natural populations in response to the high rate of contemporary climatic change. Organisms that have evolved in environments that experience high variability across space and time are of particular interest as they may harbor genetic variation that can facilitate evolutionary response to changing conditions. Here we review what is known about genetic capacity for adaptation in the purple sea urchin, Strongylocentrotus purpuratus, a species that has evolved in the upwelling ecosystem of the Northeast Pacific Ocean. We also present new results testing for adaptation to local pH conditions in six populations from Oregon to southern California. We integrate data on 19,493 genetic polymorphisms with data on local pH conditions. We find correlations between allele frequency and rank average time spent at pH <7.8 in 318 single-nucleotide polymorphisms in 275 genes. Two of the genes most correlated with local pH are a protein associated with the cytoskeleton and a proton pump, with functional roles in maintenance of cell volume and with internal regulation of pH, respectively. Across all loci tested, high correlations with local pH were concentrated in genes related to transport of ions, biomineralization, lipid metabolism, and cell-cell adhesion, functional pathways important for maintaining homeostasis at low pH. We identify a set of seven genes as top candidates for rapid evolutionary response to acidification of the ocean. In these genes, the putative low-pH-adapted allele, based on allele frequencies in natural populations, rapidly increases in frequency in purple sea urchin larvae raised at low pH. We also found that populations from localities with high pH show a greater change in allele frequency toward putative low-pH-adapted alleles under experimental acidification, compared with low-pH populations, suggesting that both natural and artificial selection favor the same alleles for response to low pH. These results illustrate that purple sea urchins may be adapted to local pH and suggest that this species may possess the genetic capacity for rapid evolution in response to acidification. This adaptive capacity likely comes from standing genetic variation maintained in nature by balancing selection across the spatial and temporal environmental mosaic that characterizes the California Current Ecosystem.
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Affiliation(s)
- M H Pespeni
- *Department of Biology, Indiana University, Bloomington, IN 47405, USA; Department of Zoology, Oregon State University, Corvallis, OR 97331, USA; Department of Biology, Stanford University, Hopkins Marine Station, Pacific Grove, CA 93950, USA
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9
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Pespeni MH, Barney BT, Palumbi SR. DIFFERENCES IN THE REGULATION OF GROWTH AND BIOMINERALIZATION GENES REVEALED THROUGH LONG-TERM COMMON-GARDEN ACCLIMATION AND EXPERIMENTAL GENOMICS IN THE PURPLE SEA URCHIN. Evolution 2013; 67:1901-14. [DOI: 10.1111/evo.12036] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 11/26/2012] [Indexed: 02/06/2023]
Affiliation(s)
- Melissa H. Pespeni
- Department of Biology; Stanford University; Hopkins Marine Station Pacific Grove California 93950
| | - Bryan T. Barney
- Department of Biology; Stanford University; Hopkins Marine Station Pacific Grove California 93950
| | - Stephen R. Palumbi
- Department of Biology; Stanford University; Hopkins Marine Station Pacific Grove California 93950
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10
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Evans TG, Chan F, Menge BA, Hofmann GE. Transcriptomic responses to ocean acidification in larval sea urchins from a naturally variable pH environment. Mol Ecol 2013; 22:1609-25. [PMID: 23317456 DOI: 10.1111/mec.12188] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 11/08/2012] [Accepted: 11/14/2012] [Indexed: 01/06/2023]
Abstract
Some marine ecosystems already experience natural declines in pH approximating those predicted with future anthropogenic ocean acidification (OA), the decline in seawater pH caused by the absorption of atmospheric CO2 . The molecular mechanisms that allow organisms to inhabit these low pH environments, particularly those building calcium carbonate skeletons, are unknown. Also uncertain is whether an enhanced capacity to cope with present day pH variation will confer resistance to future OA. To address these issues, we monitored natural pH dynamics within an intertidal habitat in the Northeast Pacific, demonstrating that upwelling exposes resident species to pH regimes not predicted to occur elsewhere until 2100. Next, we cultured the progeny of adult purple sea urchins (Strongylocentrotus purpuratus) collected from this region in CO2 -acidified seawater representing present day and near future ocean scenarios and monitored gene expression using transcriptomics. We hypothesized that persistent exposure to upwelling during evolutionary history will have selected for increased pH tolerance in this population and that their transcriptomic response to low pH seawater would provide insight into mechanisms underlying pH tolerance in a calcifying species. Resulting expression patterns revealed two important trends. Firstly, S. purpuratus larvae may alter the bioavailability of calcium and adjust skeletogenic pathways to sustain calcification in a low pH ocean. Secondly, larvae use different strategies for coping with different magnitudes of pH stress: initiating a robust transcriptional response to present day pH regimes but a muted response to near future conditions. Thus, an enhanced capacity to cope with present day pH variation may not translate into success in future oceans.
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Affiliation(s)
- Tyler G Evans
- Department of Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA 93106-9620, USA.
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11
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Pespeni MH, Garfield DA, Manier MK, Palumbi SR. Genome-wide polymorphisms show unexpected targets of natural selection. Proc Biol Sci 2011; 279:1412-20. [PMID: 21993504 DOI: 10.1098/rspb.2011.1823] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Natural selection can act on all the expressed genes of an individual, leaving signatures of genetic differentiation or diversity at many loci across the genome. New power to assay these genome-wide effects of selection comes from associating multi-locus patterns of polymorphism with gene expression and function. Here, we performed one of the first genome-wide surveys in a marine species, comparing purple sea urchins, Strongylocentrotus purpuratus, from two distant locations along the species' wide latitudinal range. We examined 9112 polymorphic loci from upstream non-coding and coding regions of genes for signatures of selection with respect to gene function and tissue- and ontogenetic gene expression. We found that genetic differentiation (F(ST)) varied significantly across functional gene classes. The strongest enrichment occurred in the upstream regions of E3 ligase genes, enzymes known to regulate protein abundance during development and environmental stress. We found enrichment for high heterozygosity in genes directly involved in immune response, particularly NALP genes, which mediate pro-inflammatory signals during bacterial infection. We also found higher heterozygosity in immune genes in the southern population, where disease incidence and pathogen diversity are greater. Similar to the major histocompatibility complex in mammals, balancing selection may enhance genetic diversity in the innate immune system genes of this invertebrate. Overall, our results show that how genome-wide polymorphism data coupled with growing databases on gene function and expression can combine to detect otherwise hidden signals of selection in natural populations.
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Affiliation(s)
- Melissa H Pespeni
- Department of Biology, Hopkins Marine Station, Stanford University, Oceanview Boulevard, Pacific Grove, CA 93950, USA.
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