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Harvey-Carroll J, Stevenson TJ, Spencer KA. Maternal developmental history alters transfer of circadian clock genes to offspring in Japanese quail (Coturnix japonica). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:399-413. [PMID: 37589732 PMCID: PMC11106187 DOI: 10.1007/s00359-023-01666-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 07/25/2023] [Accepted: 08/02/2023] [Indexed: 08/18/2023]
Abstract
Maternal signals shape embryonic development, and in turn post-natal phenotypes. RNA deposition is one such method of maternal signalling and circadian rhythms are one trait thought to be maternally inherited, through this mechanism. These maternal circadian gene transcripts aid development of a functioning circadian system. There is increasing evidence that maternal signals can be modified, depending on prevailing environmental conditions to optimise offspring fitness. However, currently, it is unknown if maternal circadian gene transcripts, and consequently early embryonic gene transcription, are altered by maternal developmental conditions. Here, using avian mothers who experienced either pre-natal corticosterone exposure, and/or post-natal stress as juveniles we were able to determine the effects of the timing of stress on downstream circadian RNA deposition in offspring. We demonstrated that maternal developmental history does indeed affect transfer of offspring circadian genes, but the timing of stress was important. Avian mothers who experienced stress during the first 2 weeks of post-natal life increased maternally deposited transcript levels of two core circadian clock genes, BMAL1 and PER2. These differences in transcript levels were transient and disappeared at the point of embryonic genome transcription. Pre-natal maternal stress alone was found to elicit delayed changes in circadian gene expression. After activation of the embryonic genome, both BMAL1 and PER2 expression were significantly decreased. If both pre-natal and post-natal stress occurred, then initial maternal transcript levels of BMAL1 were significantly increased. Taken together, these results suggest that developmental stress differentially produces persistent transgenerational effects on offspring circadian genes.
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Affiliation(s)
- Jessica Harvey-Carroll
- School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews, KY16 9JP, UK.
- Department of Biological and Environmental Sciences, University of Gothenburg, Medicinaregatan 18A, 413 90, Gothenburg, Sweden.
| | - Tyler J Stevenson
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, G36 1QH, UK
| | - Karen A Spencer
- School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews, KY16 9JP, UK
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2
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Zimmerman H, Tolman D, Reichard M. Low incidence of cannibalism among brood parasitic cuckoo catfish embryos. Behav Ecol 2023; 34:521-527. [PMID: 37434635 PMCID: PMC10332450 DOI: 10.1093/beheco/arad024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/06/2023] [Accepted: 03/22/2023] [Indexed: 07/13/2023] Open
Abstract
Brood parasites have demanding needs of host resources. Brood parasitic offspring are highly competitive and frequently cause the failure of host broods and the survival of a single parasitic offspring. Accordingly, virulent brood parasites lay a single egg in the same host nest to avoid sibling competition. In the cuckoo catfish (Synodontis multipunctatus), which parasitize mouthbrooding cichlid fishes in Lake Tanganyika, the modes of host and parasite oviposition lead to frequent cases of multiple parasitism. We experimentally tested the prediction that multiple parasitism leads to frequent cannibalism among offspring. Cuckoo catfish embryos prey upon host offspring to obtain nourishment during their 3-week development in the host buccal cavity and may also consume conspecific embryos. The potential benefits of cannibalism in the system are, therefore, twofold; to decrease competition for limited resources (i.e., host brood with rich yolk sacs) and to directly obtain nourishment by consuming rivals. We found that cannibalism indeed provided measurable benefits in terms of increased growth of the cannibals, but cannibalism was rare and typically occurred once all host offspring had been consumed. This implies that cannibalism among cuckoo catfish embryos emerges to mitigate starvation rather than eliminate competition.
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Affiliation(s)
- Holger Zimmerman
- Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 00, Brno, Czech Republic
| | - Deryk Tolman
- Institute of Vertebrate Biology, Czech Academy of Sciences, Květná 8, 603 00, Brno, Czech Republic
- Helsinki Institute of Life Sciences, University of Helsinki, Yliopistonkatu 3, 00014 Helsinki, Finland
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3
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Harry ND, Zakas C. Maternal patterns of inheritance alter transcript expression in eggs. BMC Genomics 2023; 24:191. [PMID: 37038099 PMCID: PMC10084599 DOI: 10.1186/s12864-023-09291-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 04/01/2023] [Indexed: 04/12/2023] Open
Abstract
BACKGROUND Modifications to early development can lead to evolutionary diversification. The early stages of development are under maternal control, as mothers produce eggs loaded with nutrients, proteins and mRNAs that direct early embryogenesis. Maternally provided mRNAs are the only expressed genes in initial stages of development and are tightly regulated. Differences in maternal mRNA provisioning could lead to phenotypic changes in embryogenesis and ultimately evolutionary changes in development. However, the extent that maternal mRNA expression in eggs can vary is unknown for most developmental models. Here, we use a species with dimorphic development- where females make eggs and larvae of different sizes and life-history modes-to investigate the extent of variation in maternal mRNA provisioning to the egg. RESULTS We find that there is significant variation in gene expression across eggs of different development modes, and that there are both qualitative and quantitative differences in mRNA expression. We separate parental effects from allelic effects, and find that both mechanisms contribute to mRNA expression differences. We also find that offspring of intraspecific crosses differentially provision their eggs based on the parental cross direction (a parental effect), which has not been previously demonstrated in reproductive traits like oogenesis. CONCLUSION We find that maternally controlled initiation of development is functionally distinct between eggs of different sizes and maternal genotypes. Both allele-specific effects and parent-of-origin effects contribute to gene expression differences in eggs. The latter indicates an intergenerational effect where a parent's genotype can affect gene expression in an egg made by the next generation.
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Affiliation(s)
- Nathan D Harry
- Department of Biological Sciences, North Carolina State University, 112 Derieux Place, Raleigh, NC, 27607, USA
| | - Christina Zakas
- Department of Biological Sciences, North Carolina State University, 112 Derieux Place, Raleigh, NC, 27607, USA.
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4
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Hagadorn MA, Hunter FK, DeLory T, Johnson MM, Pitts-Singer TL, Kapheim KM. Maternal body condition and season influence RNA deposition in the oocytes of alfalfa leafcutting bees ( Megachile rotundata). Front Genet 2023; 13:1064332. [PMID: 36685934 PMCID: PMC9845908 DOI: 10.3389/fgene.2022.1064332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 11/28/2022] [Indexed: 01/06/2023] Open
Abstract
Maternal effects are an important source of phenotypic variance, whereby females influence offspring developmental trajectory beyond direct genetic contributions, often in response to changing environmental conditions. However, relatively little is known about the mechanisms by which maternal experience is translated into molecular signals that shape offspring development. One such signal may be maternal RNA transcripts (mRNAs and miRNAs) deposited into maturing oocytes. These regulate the earliest stages of development of all animals, but are understudied in most insects. Here we investigated the effects of female internal (body condition) and external (time of season) environmental conditions on maternal RNA in the maturing oocytes and 24-h-old eggs (24-h eggs) of alfalfa leafcutting bees. Using gene expression and WGCNA analysis, we found that females adjust the quantity of mRNAs related to protein phosphorylation, transcriptional regulation, and nuclease activity deposited into maturing oocytes in response to both poor body condition and shorter day lengths that accompany the late season. However, the magnitude of these changes was higher for time of season. Females also adjusted miRNA deposition in response to seasonal changes, but not body condition. We did not observe significant changes in maternal RNAs in response to either body condition or time of season in 24-h eggs, which were past the maternal-to-zygotic transition. Our results suggest that females adjust the RNA transcripts they provide for offspring to regulate development in response to both internal and external environmental cues. Variation in maternal RNAs may, therefore, be important for regulating offspring phenotype in response to environmental change.
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Affiliation(s)
- Mallory A. Hagadorn
- Department of Biology, Department of Biology, Utah State University, Logan, UT, United States
| | - Frances K. Hunter
- Department of Biology, Department of Biology, Utah State University, Logan, UT, United States
| | - Tim DeLory
- Department of Biology, Department of Biology, Utah State University, Logan, UT, United States
| | - Makenna M. Johnson
- Department of Biology, Department of Biology, Utah State University, Logan, UT, United States,United States Department of Agriculture, Agricultural Research Service, Pollinating Insects Research Unit, Logan, UT, United States
| | - Theresa L. Pitts-Singer
- United States Department of Agriculture, Agricultural Research Service, Pollinating Insects Research Unit, Logan, UT, United States
| | - Karen M. Kapheim
- Department of Biology, Department of Biology, Utah State University, Logan, UT, United States,*Correspondence: Karen M. Kapheim ,
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Ahi EP, Richter F, Sefc KM. Gene expression patterns associated with caudal fin shape in the cichlid Lamprologus tigripictilis. HYDROBIOLOGIA 2022; 850:2257-2273. [PMID: 37325486 PMCID: PMC10261199 DOI: 10.1007/s10750-022-05068-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 10/12/2022] [Accepted: 10/18/2022] [Indexed: 06/17/2023]
Abstract
Variation in fin shape is one of the most prominent features of morphological diversity among fish. Regulation of fin growth has mainly been studied in zebrafish, and it is not clear whether the molecular mechanisms underlying shape variation are equally diverse or rather conserved across species. In the present study, expression levels of 37 candidate genes were tested for association with fin shape in the cichlid fish Lamprologus tigripictilis. The tested genes included members of a fin shape-associated gene regulatory network identified in a previous study and novel candidates selected within this study. Using both intact and regenerating fin tissue, we tested for expression differences between the elongated and the short regions of the spade-shaped caudal fin and identified 20 genes and transcription factors (including angptl5, cd63, csrp1a, cx43, esco2, gbf1, and rbpj), whose expression patterns were consistent with a role in fin growth. Collated with available gene expression data of two other cichlid species, our study not only highlights several genes that were correlated with fin growth in all three species (e.g., angptl5, cd63, cx43, and mmp9), but also reveals species-specific gene expression and correlation patterns, which indicate considerable divergence in the regulatory mechanisms of fin growth across cichlids. Supplementary Information The online version contains supplementary material available at 10.1007/s10750-022-05068-4.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
| | - Florian Richter
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Kristina M. Sefc
- Institute of Biology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
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6
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Chille E, Strand E, Neder M, Schmidt V, Sherman M, Mass T, Putnam H. Developmental series of gene expression clarifies maternal mRNA provisioning and maternal-to-zygotic transition in a reef-building coral. BMC Genomics 2021; 22:815. [PMID: 34763678 PMCID: PMC8588723 DOI: 10.1186/s12864-021-08114-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 10/18/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Maternal mRNA provisioning of oocytes regulates early embryogenesis. Maternal transcripts are degraded as zygotic genome activation (ZGA) intensifies, a phenomenon known as the maternal-to-zygotic transition (MZT). Here, we examine gene expression over nine developmental stages in the Pacific rice coral, Montipora capitata, from eggs and embryos at 1, 4, 9, 14, 22, and 36 h-post-fertilization (hpf), as well as swimming larvae (9d), and adult colonies. RESULTS Weighted Gene Coexpression Network Analysis revealed four expression peaks, identifying the maternal complement, two waves of the MZT, and adult expression. Gene ontology enrichment revealed maternal mRNAs are dominated by cell division, methylation, biosynthesis, metabolism, and protein/RNA processing and transport functions. The first MZT wave occurs from ~4-14 hpf and is enriched in terms related to biosynthesis, methylation, cell division, and transcription. In contrast, functional enrichment in the second MZT wave, or ZGA, from 22 hpf-9dpf, includes ion/peptide transport and cell signaling. Finally, adult expression is enriched for functions related to signaling, metabolism, and ion/peptide transport. Our proposed MZT timing is further supported by expression of enzymes involved in zygotic transcriptional repression (Kaiso) and activation (Sox2), which peak at 14 hpf and 22 hpf, respectively. Further, DNA methylation writing (DNMT3a) and removing (TET1) enzymes peak and remain stable past ~4 hpf, suggesting that methylome programming occurs before 4 hpf. CONCLUSIONS Our high-resolution insight into the coral maternal mRNA and MZT provides essential baseline information to understand parental carryover effects and the sensitivity of developmental success under increasing environmental stress.
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Affiliation(s)
- Erin Chille
- Department of Biological Sciences, University of Rhode Island, Rhode Island, USA.
| | - Emma Strand
- Department of Biological Sciences, University of Rhode Island, Rhode Island, USA
| | - Mayaan Neder
- Department of Marine Biology, The Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
- The Interuniversity Institute of Marine Science, 88103, Eilat, Israel
| | | | - Madeleine Sherman
- Department of Biological Sciences, University of Rhode Island, Rhode Island, USA
| | - Tali Mass
- Department of Marine Biology, The Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
| | - Hollie Putnam
- Department of Biological Sciences, University of Rhode Island, Rhode Island, USA
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7
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Lecaudey LA, Singh P, Sturmbauer C, Duenser A, Gessl W, Ahi EP. Transcriptomics unravels molecular players shaping dorsal lip hypertrophy in the vacuum cleaner cichlid, Gnathochromis permaxillaris. BMC Genomics 2021; 22:506. [PMID: 34225643 PMCID: PMC8256507 DOI: 10.1186/s12864-021-07775-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/18/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Teleosts display a spectacular diversity of craniofacial adaptations that often mediates ecological specializations. A considerable amount of research has revealed molecular players underlying skeletal craniofacial morphologies, but less is known about soft craniofacial phenotypes. Here we focus on an example of lip hypertrophy in the benthivorous Lake Tangnayika cichlid, Gnathochromis permaxillaris, considered to be a morphological adaptation to extract invertebrates out of the uppermost layer of mud bottom. We investigate the molecular and regulatory basis of lip hypertrophy in G. permaxillaris using a comparative transcriptomic approach. RESULTS We identified a gene regulatory network involved in tissue overgrowth and cellular hypertrophy, potentially associated with the formation of a locally restricted hypertrophic lip in a teleost fish species. Of particular interest were the increased expression level of apoda and fhl2, as well as reduced expression of cyp1a, gimap8, lama5 and rasal3, in the hypertrophic lip region which have been implicated in lip formation in other vertebrates. Among the predicted upstream transcription factors, we found reduced expression of foxp1 in the hypertrophic lip region, which is known to act as repressor of cell growth and proliferation, and its function has been associated with hypertrophy of upper lip in human. CONCLUSION Our results provide a genetic foundation for future studies of molecular players shaping soft and exaggerated, but locally restricted, craniofacial morphological changes in fish and perhaps across vertebrates. In the future, we advocate integrating gene regulatory networks of various craniofacial phenotypes to understand how they collectively govern trophic and behavioural adaptations.
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Affiliation(s)
- Laurène Alicia Lecaudey
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Pooja Singh
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria
- Department of Biological Sciences, University of Calgary, 2500 University Dr NW, Calgary, AB T2N 1N4 Canada
| | - Christian Sturmbauer
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria
| | - Anna Duenser
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria
| | - Wolfgang Gessl
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria
| | - Ehsan Pashay Ahi
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Viikinkaari 9, 00014 Helsinki, Finland
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8
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Beatty AE, Mote DM, Schwartz TS. Tails of reproduction: Regeneration leads to increased reproductive investment. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:522-528. [PMID: 33970527 DOI: 10.1002/jez.2472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/29/2021] [Accepted: 04/26/2021] [Indexed: 11/11/2022]
Abstract
Trade-offs between life-history traits are due to limited resources or constraints in the regulation of genetic and physiological networks. Tail autotomy, with subsequent regeneration, is a common anti-predation mechanism in lizards and is predicted to trade-off with life-history traits, such as reproduction. We utilize the brown anole lizard with its unusual reproductive pattern of single-egg clutches every 7-10 days to test for a trade-off in reproductive investment over 8 weeks of tail regeneration on a limited diet. In contrast to predictions, we found that investing in tissue regeneration had a positive effect on reproduction in terms of egg size (11.7% relative to controls) and hatchling size (11.5% relative to controls), and no effect on egg number or survival, with the increase in reproduction starting at peak regeneration. We discuss mechanistic hypotheses that the process of regeneration may cause increased energetic efficiency or utilized shared physiological pathways with reproductive investment.
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Affiliation(s)
- Abby E Beatty
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - David M Mote
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Tonia S Schwartz
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
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9
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Beck SV, Räsänen K, Leblanc CA, Skúlason S, Jónsson ZO, Kristjánsson BK. Differences among families in craniofacial shape at early life-stages of Arctic charr (Salvelinus alpinus). BMC DEVELOPMENTAL BIOLOGY 2020; 20:21. [PMID: 33106153 PMCID: PMC7586659 DOI: 10.1186/s12861-020-00226-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 10/15/2020] [Indexed: 11/10/2022]
Abstract
BACKGROUND Organismal fitness can be determined at early life-stages, but phenotypic variation at early life-stages is rarely considered in studies on evolutionary diversification. The trophic apparatus has been shown to contribute to sympatric resource-mediated divergence in several taxa. However, processes underlying diversification in trophic traits are poorly understood. Using phenotypically variable Icelandic Arctic charr (Salvelinus alpinus), we reared offspring from multiple families under standardized laboratory conditions and tested to what extent family (i.e. direct genetic and maternal effects) contributes to offspring morphology at hatching (H) and first feeding (FF). To understand the underlying mechanisms behind early life-stage variation in morphology, we examined how craniofacial shape varied according to family, offspring size, egg size and candidate gene expression. RESULTS Craniofacial shape (i.e. the Meckel's cartilage and hyoid arch) was more variable between families than within families both across and within developmental stages. Differences in craniofacial morphology between developmental stages correlated with offspring size, whilst within developmental stages only shape at FF correlated with offspring size, as well as female mean egg size. Larger offspring and offspring from females with larger eggs consistently had a wider hyoid arch and contracted Meckel's cartilage in comparison to smaller offspring. CONCLUSIONS This study provides evidence for family-level variation in early life-stage trophic morphology, indicating the potential for parental effects to facilitate resource polymorphism.
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Affiliation(s)
- Samantha V Beck
- Department of Aquaculture and Fish Biology, Hólar University, 551, Sauðárkrókur, Iceland. .,Institute of Life- and Environmental Sciences, University of Iceland, Reykjavík, Iceland. .,The Rivers and Lochs Institute, University of the Highlands and Islands, Inverness, UK.
| | - Katja Räsänen
- Department of Aquatic Ecology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland.,Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland
| | - Camille A Leblanc
- Department of Aquaculture and Fish Biology, Hólar University, 551, Sauðárkrókur, Iceland
| | - Skúli Skúlason
- Department of Aquaculture and Fish Biology, Hólar University, 551, Sauðárkrókur, Iceland
| | - Zophonías O Jónsson
- Institute of Life- and Environmental Sciences, University of Iceland, Reykjavík, Iceland
| | - Bjarni K Kristjánsson
- Department of Aquaculture and Fish Biology, Hólar University, 551, Sauðárkrókur, Iceland
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10
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Diaz F, Kuijper B, Hoyle RB, Talamantes N, Coleman JM, Matzkin LM. Environmental predictability drives adaptive within‐ and transgenerational plasticity of heat tolerance across life stages and climatic regions. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13704] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fernando Diaz
- Department of Entomology University of Arizona Tucson AZ USA
| | - Bram Kuijper
- Center for Ecology and Conservation University of Exeter Penryn UK
| | - Rebecca B. Hoyle
- School of Mathematical Sciences University of Southampton Southampton UK
| | | | | | - Luciano M. Matzkin
- Department of Entomology University of Arizona Tucson AZ USA
- BIO5 InstituteUniversity of Arizona Tucson AZ USA
- Department of Ecology and Evolutionary Biology University of Arizona Tucson AZ USA
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11
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Rahman MM, Biswas R, Gazi L, Arafat ST, Rahman MM, Asaduzzaman M, Rahman SM, Ahsan MN. Annually twice induced spawnings provide multiple benefits: Experimental evidence from an Indian major carp (
Catla catla
, Hamilton 1822). AQUACULTURE RESEARCH 2020; 51:2275-2290. [DOI: 10.1111/are.14572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 02/07/2020] [Indexed: 09/27/2023]
Affiliation(s)
- Md. Moshiur Rahman
- Tokyo University of Marine Science and Technology Tokyo Japan
- Fisheries and Marine Resource Technology Discipline Khulna University Khulna Bangladesh
| | - Ripon Biswas
- Fisheries and Marine Resource Technology Discipline Khulna University Khulna Bangladesh
| | - Litan Gazi
- Fisheries and Marine Resource Technology Discipline Khulna University Khulna Bangladesh
| | - Shaikh Tareq Arafat
- Fisheries and Marine Resource Technology Discipline Khulna University Khulna Bangladesh
| | - Md. Mostafizur Rahman
- Department of Disaster and Human Security Management Bangladesh University of Professionals Dhaka Bangladesh
| | - Md. Asaduzzaman
- Department of Marine Bioresource Science Chattogram Veterinary and Animal Sciences University Chittagong Bangladesh
| | - Sheikh Mustafizur Rahman
- Fisheries and Marine Resource Technology Discipline Khulna University Khulna Bangladesh
- Fish Resources Research Center King Faisal University Hofuf Saudi Arabia
| | - Md. Nazmul Ahsan
- Fisheries and Marine Resource Technology Discipline Khulna University Khulna Bangladesh
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12
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Ahi EP, Duenser A, Singh P, Gessl W, Sturmbauer C. Appetite regulating genes may contribute to herbivory versus carnivory trophic divergence in haplochromine cichlids. PeerJ 2020; 8:e8375. [PMID: 31998557 PMCID: PMC6977467 DOI: 10.7717/peerj.8375] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 12/09/2019] [Indexed: 12/14/2022] Open
Abstract
Feeding is a complex behaviour comprised of satiety control, foraging, ingestion and subsequent digestion. Cichlids from the East African Great Lakes are renowned for their diverse trophic specializations, largely predicated on highly variable jaw morphologies. Thus, most research has focused on dissecting the genetic, morphological and regulatory basis of jaw and teeth development in these species. Here for the first time we explore another aspect of feeding, the regulation of appetite related genes that are expressed in the brain and control satiety in cichlid fishes. Using qPCR analysis, we first validate stably expressed reference genes in the brain of six haplochromine cichlid species at the end of larval development prior to foraging. We next evaluate the expression of 16 appetite related genes in herbivorous and carnivorous species from the parallel radiations of Lake Tanganyika, Malawi and Victoria. Interestingly, we find increased expression of two appetite-regulating genes (anorexigenic genes), cart and npy2r, in the brain of carnivorous species in all the three lakes. This supports the notion that appetite gene regulation might play a part in determining trophic niche specialization in divergent cichlid species, already prior to exposure to different diets. Our study contributes to the limited body of knowledge on the neurological circuitry that controls feeding transitions and adaptations in cichlids and other teleosts.
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Affiliation(s)
- Ehsan P. Ahi
- Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
- Institute of Biology, University of Graz, Graz, Austria
| | - Anna Duenser
- Institute of Biology, University of Graz, Graz, Austria
| | - Pooja Singh
- Institute of Biology, University of Graz, Graz, Austria
- Institute of Biological Sciences, University of Calgary, Calgary, Canada
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13
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Ahi EP, Lecaudey LA, Ziegelbecker A, Steiner O, Glabonjat R, Goessler W, Hois V, Wagner C, Lass A, Sefc KM. Comparative transcriptomics reveals candidate carotenoid color genes in an East African cichlid fish. BMC Genomics 2020; 21:54. [PMID: 31948394 PMCID: PMC6966818 DOI: 10.1186/s12864-020-6473-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 01/09/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Carotenoids contribute significantly to animal body coloration, including the spectacular color pattern diversity among fishes. Fish, as other animals, derive carotenoids from their diet. Following uptake, transport and metabolic conversion, carotenoids allocated to body coloration are deposited in the chromatophore cells of the integument. The genes involved in these processes are largely unknown. Using RNA-Sequencing, we tested for differential gene expression between carotenoid-colored and white skin regions of a cichlid fish, Tropheus duboisi "Maswa", to identify genes associated with carotenoid-based integumentary coloration. To control for positional gene expression differences that were independent of the presence/absence of carotenoid coloration, we conducted the same analyses in a closely related population, in which both body regions are white. RESULTS A larger number of genes (n = 50) showed higher expression in the yellow compared to the white skin tissue than vice versa (n = 9). Of particular interest was the elevated expression level of bco2a in the white skin samples, as the enzyme encoded by this gene catalyzes the cleavage of carotenoids into colorless derivatives. The set of genes with higher expression levels in the yellow region included genes involved in xanthophore formation (e.g., pax7 and sox10), intracellular pigment mobilization (e.g., tubb, vim, kif5b), as well as uptake (e.g., scarb1) and storage (e.g., plin6) of carotenoids, and metabolic conversion of lipids and retinoids (e.g., dgat2, pnpla2, akr1b1, dhrs). Triglyceride concentrations were similar in the yellow and white skin regions. Extracts of integumentary carotenoids contained zeaxanthin, lutein and beta-cryptoxanthin as well as unidentified carotenoid structures. CONCLUSION Our results suggest a role of carotenoid cleavage by Bco2 in fish integumentary coloration, analogous to previous findings in birds. The elevated expression of genes in carotenoid-rich skin regions with functions in retinol and lipid metabolism supports hypotheses concerning analogies and shared mechanisms between these metabolic pathways. Overlaps in the sets of differentially expressed genes (including dgat2, bscl2, faxdc2 and retsatl) between the present study and previous, comparable studies in other fish species provide useful hints to potential carotenoid color candidate genes.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
- Department of Comparative Physiology, Uppsala University, Norbyvägen 18A, SE-75 236 Uppsala, Sweden
| | - Laurène A. Lecaudey
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Angelika Ziegelbecker
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
| | - Oliver Steiner
- Institute of Chemistry, University of Graz, Universitätsplatz 1, A-8010, Graz, Austria
| | - Ronald Glabonjat
- Institute of Chemistry, University of Graz, Universitätsplatz 1, A-8010, Graz, Austria
| | - Walter Goessler
- Institute of Chemistry, University of Graz, Universitätsplatz 1, A-8010, Graz, Austria
| | - Victoria Hois
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, 8010, Graz, Austria
| | - Carina Wagner
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, 8010, Graz, Austria
| | - Achim Lass
- Institute of Molecular Biosciences, University of Graz, Heinrichstraße 31/II, 8010, Graz, Austria
- BioTechMed-Graz, 8010 Graz, Austria
| | - Kristina M. Sefc
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
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14
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Lecaudey LA, Sturmbauer C, Singh P, Ahi EP. Molecular mechanisms underlying nuchal hump formation in dolphin cichlid, Cyrtocara moorii. Sci Rep 2019; 9:20296. [PMID: 31889116 PMCID: PMC6937230 DOI: 10.1038/s41598-019-56771-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 12/12/2019] [Indexed: 12/15/2022] Open
Abstract
East African cichlid fishes represent a model to tackle adaptive changes and their connection to rapid speciation and ecological distinction. In comparison to bony craniofacial tissues, adaptive morphogenesis of soft tissues has been rarely addressed, particularly at the molecular level. The nuchal hump in cichlids fishes is one such soft-tissue and exaggerated trait that is hypothesized to play an innovative role in the adaptive radiation of cichlids fishes. It has also evolved in parallel across lakes in East Africa and Central America. Using gene expression profiling, we identified and validated a set of genes involved in nuchal hump formation in the Lake Malawi dolphin cichlid, Cyrtocara moorii. In particular, we found genes differentially expressed in the nuchal hump, which are involved in controlling cell proliferation (btg3, fosl1a and pdgfrb), cell growth (dlk1), craniofacial morphogenesis (dlx5a, mycn and tcf12), as well as regulators of growth-related signals (dpt, pappa and socs2). This is the first study to identify the set of genes associated with nuchal hump formation in cichlids. Given that the hump is a trait that evolved repeatedly in several African and American cichlid lineages, it would be interesting to see if the molecular pathways and genes triggering hump formation follow a common genetic track or if the trait evolved in parallel, with distinct mechanisms, in other cichlid adaptive radiations and even in other teleost fishes.
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Affiliation(s)
- Laurène Alicia Lecaudey
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway
| | - Christian Sturmbauer
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
| | - Pooja Singh
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
- Institute of Biological Sciences, University of Calgary, 2500 University Dr NW, Calgary, AB, T2N 1N4, Canada
| | - Ehsan Pashay Ahi
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria.
- Department of Comparative Physiology, Uppsala University, Norbyvägen 18A, SE-75 236, Uppsala, Sweden.
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15
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Ahi EP, Brunel M, Tsakoumis E, Schmitz M. Transcriptional study of appetite regulating genes in the brain of zebrafish (Danio rerio) with impaired leptin signalling. Sci Rep 2019; 9:20166. [PMID: 31882937 PMCID: PMC6934527 DOI: 10.1038/s41598-019-56779-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 12/10/2019] [Indexed: 12/26/2022] Open
Abstract
The hormone leptin is a key regulator of body weight, food intake and metabolism. In mammals, leptin acts as an anorexigen and inhibits food intake centrally by affecting the appetite centres in the hypothalamus. In teleost fish, the regulatory connections between leptin and other appetite-regulating genes are largely unknown. In the present study, we used a zebrafish mutant with a loss of function leptin receptor to investigate brain expression patterns of 12 orexigenic and 24 anorexigenic genes under different feeding conditions (normal feeding, 7-day fasting, 2 and 6-hours refeeding). Expression patterns were compared to wild-type zebrafish, in order to identify leptin-dependent differentially expressed genes under different feeding conditions. We provide evidence that the transcription of certain orexigenic and anorexigenic genes is influenced by leptin signalling in the zebrafish brain. We found that the expression of orexigenic genes was not affected by impaired leptin signalling under normal feeding conditions; however, several orexigenic genes showed increased transcription during fasting and refeeding, including agrp, apln, galr1a and cnr1. This suggests an inhibitory effect of leptin signal on the transcription of these orexigenic genes during short-term fasting and refeeding in functional zebrafish. Most pronounced effects were observed in the group of anorexigenic genes, where the impairment of leptin signalling resulted in reduced gene expression in several genes, including cart family, crhb, gnrh2, mc4r, pomc and spx, in the control group. This suggests a stimulatory effect of leptin signal on the transcription of these anorexigenic genes under normal feeding condition. In addition, we found multiple gain and loss in expression correlations between the appetite-regulating genes, in zebrafish with impaired leptin signal, suggesting the presence of gene regulatory networks downstream of leptin signal in zebrafish brain. The results provide the first evidence for the effects of leptin signal on the transcription of various appetite-regulating genes in zebrafish brain, under different feeding conditions. Altogether, these transcriptional changes suggest an anorexigenic role for leptin signal, which is likely to be mediated through distinct set of appetite-regulating genes under different feeding conditions.
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Affiliation(s)
- Ehsan Pashay Ahi
- Department of Organismal Biology, Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, SE-752 36, Uppsala, Sweden
| | - Mathilde Brunel
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, BioCentrum, Allmas Allé 5, SE-750 07 Uppsala, Sweden
| | - Emmanouil Tsakoumis
- Department of Organismal Biology, Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, SE-752 36, Uppsala, Sweden
| | - Monika Schmitz
- Department of Organismal Biology, Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, SE-752 36, Uppsala, Sweden.
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16
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Skúlason S, Parsons KJ, Svanbäck R, Räsänen K, Ferguson MM, Adams CE, Amundsen P, Bartels P, Bean CW, Boughman JW, Englund G, Guðbrandsson J, Hooker OE, Hudson AG, Kahilainen KK, Knudsen R, Kristjánsson BK, Leblanc CA, Jónsson Z, Öhlund G, Smith C, Snorrason SS. A way forward with eco evo devo: an extended theory of resource polymorphism with postglacial fishes as model systems. Biol Rev Camb Philos Soc 2019; 94:1786-1808. [PMID: 31215138 PMCID: PMC6852119 DOI: 10.1111/brv.12534] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/12/2019] [Accepted: 05/20/2019] [Indexed: 12/16/2022]
Abstract
A major goal of evolutionary science is to understand how biological diversity is generated and altered. Despite considerable advances, we still have limited insight into how phenotypic variation arises and is sorted by natural selection. Here we argue that an integrated view, which merges ecology, evolution and developmental biology (eco evo devo) on an equal footing, is needed to understand the multifaceted role of the environment in simultaneously determining the development of the phenotype and the nature of the selective environment, and how organisms in turn affect the environment through eco evo and eco devo feedbacks. To illustrate the usefulness of an integrated eco evo devo perspective, we connect it with the theory of resource polymorphism (i.e. the phenotypic and genetic diversification that occurs in response to variation in available resources). In so doing, we highlight fishes from recently glaciated freshwater systems as exceptionally well-suited model systems for testing predictions of an eco evo devo framework in studies of diversification. Studies on these fishes show that intraspecific diversity can evolve rapidly, and that this process is jointly facilitated by (i) the availability of diverse environments promoting divergent natural selection; (ii) dynamic developmental processes sensitive to environmental and genetic signals; and (iii) eco evo and eco devo feedbacks influencing the selective and developmental environments of the phenotype. We highlight empirical examples and present a conceptual model for the generation of resource polymorphism - emphasizing eco evo devo, and identify current gaps in knowledge.
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Affiliation(s)
- Skúli Skúlason
- Department of Aquaculture and Fish BiologyHólar UniversitySauðárkrókur, 551Iceland
- Icelandic Museum of Natural History, Brynjólfsgata 5ReykjavíkIS‐107Iceland
| | - Kevin J. Parsons
- Institute of Biodiversity, Animal Health & Comparative MedicineUniversity of GlasgowGlasgow, G12 8QQU.K.
| | - Richard Svanbäck
- Animal Ecology, Department of Ecology and Genetics, Science for Life LaboratoryUppsala University, Norbyvägen 18DUppsala, SE‐752 36Sweden
| | - Katja Räsänen
- Department of Aquatic EcologyEAWAG, Swiss Federal Institute of Aquatic Science and Technology, and Institute of Integrative Biology, ETH‐Zurich, Ueberlandstrasse 133CH‐8600DübendorfSwitzerland
| | - Moira M. Ferguson
- Department of Integrative BiologyUniversity of GuelphGuelph, Ontario N1G 2W1Canada
| | - Colin E. Adams
- Scottish Centre for Ecology and the Natural Environment, IBAHCMUniversity of GlasgowGlasgow G12 8QQU.K.
| | - Per‐Arne Amundsen
- Freshwater Ecology Group, Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and EconomicsUniversity of TromsöTromsö, N‐9037Norway
| | - Pia Bartels
- Department of Ecology and Environmental ScienceUmeå UniversityUmeå, SE‐90187Sweden
| | - Colin W. Bean
- Scottish Natural Heritage, Caspian House, Mariner Court, Clydebank Business ParkClydebank, G81 2NRU.K.
| | - Janette W. Boughman
- Department of Integrative BiologyMichigan State UniversityEast Lansing, MI 48824U.S.A.
| | - Göran Englund
- Department of Ecology and Environmental ScienceUmeå UniversityUmeå, SE‐90187Sweden
| | - Jóhannes Guðbrandsson
- Institute of Life and Environmental SciencesUniversity of IcelandReykjavik, 101Iceland
| | | | - Alan G. Hudson
- Department of Ecology and Environmental ScienceUmeå UniversityUmeå, SE‐90187Sweden
| | - Kimmo K. Kahilainen
- Inland Norway University of Applied Sciences, Department of Forestry and Wildlife Management, Campus Evenstad, Anne Evenstadvei 80Koppang, NO‐2480Norway
| | - Rune Knudsen
- Freshwater Ecology Group, Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and EconomicsUniversity of TromsöTromsö, N‐9037Norway
| | | | - Camille A‐L. Leblanc
- Department of Aquaculture and Fish BiologyHólar UniversitySauðárkrókur, 551Iceland
| | - Zophonías Jónsson
- Institute of Life and Environmental SciencesUniversity of IcelandReykjavik, 101Iceland
| | - Gunnar Öhlund
- Department of Ecology and Environmental ScienceUmeå UniversityUmeå, SE‐90187Sweden
| | - Carl Smith
- School of BiologyUniversity of St Andrews, St. AndrewsFife, KY16 9AJU.K.
| | - Sigurður S. Snorrason
- Institute of Life and Environmental SciencesUniversity of IcelandReykjavik, 101Iceland
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17
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Ahi EP, Singh P, Duenser A, Gessl W, Sturmbauer C. Divergence in larval jaw gene expression reflects differential trophic adaptation in haplochromine cichlids prior to foraging. BMC Evol Biol 2019; 19:150. [PMID: 31340758 PMCID: PMC6657104 DOI: 10.1186/s12862-019-1483-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/18/2019] [Indexed: 12/11/2022] Open
Abstract
Background Understanding how variation in gene expression contributes to morphological diversity is a major goal in evolutionary biology. Cichlid fishes from the East African Great lakes exhibit striking diversity in trophic adaptations predicated on the functional modularity of their two sets of jaws (oral and pharyngeal). However, the transcriptional basis of this modularity is not so well understood, as no studies thus far have directly compared the expression of genes in the oral and pharyngeal jaws. Nor is it well understood how gene expression may have contributed to the parallel evolution of trophic morphologies across the replicate cichlid adaptive radiations in Lake Tanganyika, Malawi and Victoria. Results We set out to investigate the role of gene expression divergence in cichlid fishes from these three lakes adapted to herbivorous and carnivorous trophic niches. We focused on the development stage prior to the onset of exogenous feeding that is critical for understanding patterns of gene expression after oral and pharyngeal jaw skeletogenesis, anticipating environmental cues. This framework permitted us for the first time to test for signatures of gene expression underlying jaw modularity in convergent eco-morphologies across three independent adaptive radiations. We validated a set of reference genes, with stable expression between the two jaw types and across species, which can be important for future studies of gene expression in cichlid jaws. Next we found evidence of modular and non-modular gene expression between the two jaws, across different trophic niches and lakes. For instance, prdm1a, a skeletogenic gene with modular anterior-posterior expression, displayed higher pharyngeal jaw expression and modular expression pattern only in carnivorous species. Furthermore, we found the expression of genes in cichlids jaws from the youngest Lake Victoria to exhibit low modularity compared to the older lakes. Conclusion Overall, our results provide cross-species transcriptional comparisons of modularly-regulated skeletogenic genes in the two jaw types, implicating expression differences which might contribute to the formation of divergent trophic morphologies at the stage of larval independence prior to foraging. Electronic supplementary material The online version of this article (10.1186/s12862-019-1483-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria. .,Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, 75236, Uppsala, Sweden.
| | - Pooja Singh
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
| | - Anna Duenser
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
| | - Wolfgang Gessl
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
| | - Christian Sturmbauer
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
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18
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Ahi EP, Richter F, Lecaudey LA, Sefc KM. Gene expression profiling suggests differences in molecular mechanisms of fin elongation between cichlid species. Sci Rep 2019; 9:9052. [PMID: 31227799 PMCID: PMC6588699 DOI: 10.1038/s41598-019-45599-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 06/11/2019] [Indexed: 01/09/2023] Open
Abstract
Comparative analyses of gene regulation inform about the molecular basis of phenotypic trait evolution. Here, we address a fin shape phenotype that evolved multiple times independently across teleost fish, including several species within the family Cichlidae. In a previous study, we proposed a gene regulatory network (GRN) involved in the formation and regeneration of conspicuous filamentous elongations adorning the unpaired fins of the Neolamprologus brichardi. Here, we tested the members of this network in the blockhead cichlid, Steatocranus casuarius, which displays conspicuously elongated dorsal and moderately elongated anal fins. Our study provided evidence for differences in the anatomy of fin elongation and suggested gene regulatory divergence between the two cichlid species. Only a subset of the 20 genes tested in S. casuarius showed the qPCR expression patterns predicted from the GRN identified in N. brichardi, and several of the gene-by-gene expression correlations differed between the two cichlid species. In comparison to N. brichardi, gene expression patterns in S. casuarius were in better (but not full) agreement with gene regulatory interactions inferred in zebrafish. Within S. casuarius, the dorsoventral asymmetry in ornament expression was accompanied by differences in gene expression patterns, including potential regulatory differentiation, between the anal and dorsal fin.
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Affiliation(s)
- Ehsan Pashay Ahi
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria. .,Department of Comparative Physiology, Uppsala University, Norbyvägen 18A, SE-75 236, Uppsala, Sweden.
| | - Florian Richter
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
| | | | - Kristina M Sefc
- Institute of Biology, University of Graz, Universitätsplatz 2, A-8010, Graz, Austria
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