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Molina-Gil S, Sotillos S, Espinosa-Vázquez JM, Almudi I, Hombría JCG. Interlocking of co-opted developmental gene networks in Drosophila and the evolution of pre-adaptive novelty. Nat Commun 2023; 14:5730. [PMID: 37714829 PMCID: PMC10504328 DOI: 10.1038/s41467-023-41414-3] [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: 12/29/2022] [Accepted: 08/30/2023] [Indexed: 09/17/2023] Open
Abstract
The re-use of genes in new organs forms the base of many evolutionary novelties. A well-characterised case is the recruitment of the posterior spiracle gene network to the Drosophila male genitalia. Here we find that this network has also been co-opted to the testis mesoderm where is required for sperm liberation, providing an example of sequentially repeated developmental co-options. Associated to this co-option event, an evolutionary expression novelty appeared, the activation of the posterior segment determinant Engrailed to the anterior A8 segment controlled by common testis and spiracle regulatory elements. Enhancer deletion shows that A8 anterior Engrailed activation is not required for spiracle development but only necessary in the testis. Our study presents an example of pre-adaptive developmental novelty: the activation of the Engrailed transcription factor in the anterior compartment of the A8 segment where, despite having no specific function, opens the possibility of this developmental factor acquiring one. We propose that recently co-opted networks become interlocked, so that any change to the network because of its function in one organ, will be mirrored by other organs even if it provides no selective advantage to them.
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Affiliation(s)
- Sara Molina-Gil
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-JA-UPO Ctra. de Utrera, km1, 41013, Seville, Spain
- Málaga Biomedical Research Institute and Andalusian Centre for Nanomedicine and Biotechnology Platform, Severo Ochoa, 35, 29590, Málaga, Spain
| | - Sol Sotillos
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-JA-UPO Ctra. de Utrera, km1, 41013, Seville, Spain
| | - José Manuel Espinosa-Vázquez
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-JA-UPO Ctra. de Utrera, km1, 41013, Seville, Spain
- Department of Food Biotechnology, Instituto de la Grasa. Campus de la Universidad Pablo de Olavide. Ctra. de Utrera, km. 1, 41013, Seville, Spain
| | - Isabel Almudi
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-JA-UPO Ctra. de Utrera, km1, 41013, Seville, Spain
- Department of Genetics, Microbiology and Statistics and Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Diagonal, 643, 08028, Barcelona, Spain
| | - James C-G Hombría
- Centro Andaluz de Biología del Desarrollo (CABD), CSIC-JA-UPO Ctra. de Utrera, km1, 41013, Seville, Spain.
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Janssen R, Turetzek N, Pechmann M. Lack of evidence for conserved parasegmental grooves in arthropods. Dev Genes Evol 2022; 232:27-37. [PMID: 35038005 PMCID: PMC8918137 DOI: 10.1007/s00427-022-00684-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/03/2022] [Indexed: 12/01/2022]
Abstract
In the arthropod model species Drosophila melanogaster, a dipteran fly, segmentation of the anterior–posterior body axis is under control of a hierarchic gene cascade. Segmental boundaries that form morphological grooves are established posteriorly within the segmental expression domain of the segment-polarity gene (SPG) engrailed (en). More important for the development of the fly, however, are the parasegmental boundaries that are established at the interface of en expressing cells and anteriorly adjacent wingless (wg) expressing cells. In Drosophila, both segmental and transient parasegmental grooves form. The latter are positioned anterior to the expression of en. Although the function of the SPGs in establishing and maintaining segmental and parasegmental boundaries is highly conserved among arthropods, parasegmental grooves have only been reported for Drosophila, and a spider (Cupiennius salei). Here, we present new data on en expression, and re-evaluate published data, from four distantly related spiders, including Cupiennius, and a distantly related chelicerate, the harvestman Phalangium opilio. Gene expression analysis of en genes in these animals does not corroborate the presence of parasegmental grooves. Consequently, our data question the general presence of parasegmental grooves in arthropods.
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Affiliation(s)
- Ralf Janssen
- Department of Earth Sciences, Uppsala University, Villavägen 16, 75236, Palaeobiology, Sweden.
| | - Natascha Turetzek
- Evolutionary Ecology, Faculty of Biology, Ludwig-Maximilians Universität München, Grosshaderner Strasse 2, 82152, Biozentrum, Germany
| | - Matthias Pechmann
- Institute for Zoology, Department of Developmental Biology, University of Cologne, Zuelpicher Str. 47b, 50674, Biocenter, Germany
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3
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Paulo DF, Williamson ME, Arp AP, Li F, Sagel A, Skoda SR, Sanchez-Gallego J, Vasquez M, Quintero G, Pérez de León AA, Belikoff EJ, Azeredo-Espin AML, McMillan WO, Concha C, Scott MJ. Specific Gene Disruption in the Major Livestock Pests Cochliomyia hominivorax and Lucilia cuprina Using CRISPR/Cas9. G3 (BETHESDA, MD.) 2019; 9:3045-3055. [PMID: 31340950 PMCID: PMC6723136 DOI: 10.1534/g3.119.400544] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/23/2019] [Indexed: 02/07/2023]
Abstract
Cochliomyia hominivorax and Lucilia cuprina are major pests of livestock. Their larvae infest warm-blooded vertebrates and feed on host's tissues, resulting in severe industry losses. As they are serious pests, considerable effort has been made to develop genomic resources and functional tools aiming to improve their management and control. Here, we report a significant addition to the pool of genome manipulation tools through the establishment of efficient CRISPR/Cas9 protocols for the generation of directed and inheritable modifications in the genome of these flies. Site-directed mutations were introduced in the C hominivorax and L cuprina yellow genes (ChY and LcY) producing lightly pigmented adults. High rates of somatic mosaicism were induced when embryos were injected with Cas9 ribonucleoprotein complexes (RNPs) pre-assembled with guide RNAs (sgRNAs) at high concentrations. Adult flies carrying disrupted yellow alleles lacked normal pigmentation (brown body phenotype) and efficiently transmitted the mutated alleles to the subsequent generation, allowing the rapid creation of homozygous strains for reverse genetics of candidate loci. We next used our established CRISPR protocol to disrupt the C hominivorax transformer gene (Chtra). Surviving females carrying mutations in the Chtra locus developed mosaic phenotypes of transformed ovipositors with characteristics of male genitalia while exhibiting abnormal reproductive tissues. The CRISPR protocol described here is a significant improvement on the existing toolkit of molecular methods in calliphorids. Our results also suggest that Cas9-based systems targeting Chtra and Lctra could be an effective means for controlling natural populations of these important pests.
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Affiliation(s)
- Daniel F Paulo
- Centre for Molecular Biology and Genetic Engineering, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas
- Laboratory of Ecological and Evolutionary Genomics, Smithsonian Tropical Research Institute, Gamboa, Panama
| | - Megan E Williamson
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh NC
| | - Alex P Arp
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Kerrville TX, and
| | - Fang Li
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh NC
| | - Agustin Sagel
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Screwworm Research Site, Pacora, Panama
| | - Steven R Skoda
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Screwworm Research Site, Pacora, Panama
| | - Joel Sanchez-Gallego
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Screwworm Research Site, Pacora, Panama
| | - Mario Vasquez
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Screwworm Research Site, Pacora, Panama
| | - Gladys Quintero
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Screwworm Research Site, Pacora, Panama
| | - Adalberto A Pérez de León
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Kerrville TX, and
| | - Esther J Belikoff
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh NC
| | - Ana M L Azeredo-Espin
- Centre for Molecular Biology and Genetic Engineering, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas
| | - W Owen McMillan
- Laboratory of Ecological and Evolutionary Genomics, Smithsonian Tropical Research Institute, Gamboa, Panama
| | - Carolina Concha
- Laboratory of Ecological and Evolutionary Genomics, Smithsonian Tropical Research Institute, Gamboa, Panama
| | - Maxwell J Scott
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh NC
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Hogvall M, Budd GE, Janssen R. Gene expression analysis of potential morphogen signalling modifying factors in Panarthropoda. EvoDevo 2018; 9:20. [PMID: 30288252 PMCID: PMC6162966 DOI: 10.1186/s13227-018-0109-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 09/04/2018] [Indexed: 11/28/2022] Open
Abstract
Background Morphogen signalling represents a key mechanism of developmental processes during animal development. Previously, several evolutionary conserved morphogen signalling pathways have been identified, and their players such as the morphogen receptors, morphogen modulating factors (MMFs) and the morphogens themselves have been studied. MMFs are factors that regulate morphogen distribution and activity. The interactions of MMFs with different morphogen signalling pathways such as Wnt signalling, Hedgehog (Hh) signalling and Decapentaplegic (Dpp) signalling are complex because some of the MMFs have been shown to interact with more than one signalling pathway, and depending on genetic context, to have different, biphasic or even opposing function. This complicates the interpretation of expression data and functional data of MMFs and may be one reason why data on MMFs in other arthropods than Drosophila are scarce or totally lacking. Results As a first step to a better understanding of the potential roles of MMFs in arthropod development, we investigate here the embryonic expression patterns of division abnormally delayed (dally), dally-like protein (dlp), shifted (shf) and secreted frizzled-related protein 125 (sFRP125) and sFRP34 in the beetle Tribolium castaneum, the spider Parasteatoda tepidariorum, the millipede Glomeris marginata and the onychophoran Euperipatoides kanangrensis. This pioneer study represents the first comprehensive comparative data set of these genes in panarthropods. Conclusions Expression profiles reveal a high degree of diversity, suggesting that MMFs may represent highly evolvable nodes in otherwise conserved gene regulatory networks. Conserved aspects of MMF expression, however, appear to concern function in segmentation and limb development, two of the key topics of evolutionary developmental research. Electronic supplementary material The online version of this article (10.1186/s13227-018-0109-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mattias Hogvall
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, Uppsala, Sweden
| | - Graham E Budd
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, Uppsala, Sweden
| | - Ralf Janssen
- Department of Earth Sciences, Palaeobiology, Uppsala University, Villavägen 16, Uppsala, Sweden
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Expression of segment polarity genes in brachiopods supports a non-segmental ancestral role of engrailed for bilaterians. Sci Rep 2016; 6:32387. [PMID: 27561213 PMCID: PMC4999882 DOI: 10.1038/srep32387] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 08/09/2016] [Indexed: 01/25/2023] Open
Abstract
The diverse and complex developmental mechanisms of segmentation have been more thoroughly studied in arthropods, vertebrates and annelids-distantly related animals considered to be segmented. Far less is known about the role of "segmentation genes" in organisms that lack a segmented body. Here we investigate the expression of the arthropod segment polarity genes engrailed, wnt1 and hedgehog in the development of brachiopods-marine invertebrates without a subdivided trunk but closely related to the segmented annelids. We found that a stripe of engrailed expression demarcates the ectodermal boundary that delimits the anterior region of Terebratalia transversa and Novocrania anomala embryos. In T. transversa, this engrailed domain is abutted by a stripe of wnt1 expression in a pattern similar to the parasegment boundaries of insects-except for the expression of hedgehog, which is restricted to endodermal tissues of the brachiopod embryos. We found that pax6 and pax2/5/8, putative regulators of engrailed, also demarcate the anterior boundary in the two species, indicating these genes might be involved in the anterior patterning of brachiopod larvae. In a comparative phylogenetic context, these findings suggest that bilaterians might share an ancestral, non-segmental domain of engrailed expression during early embryogenesis.
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Martín-Vega D, Hall MJR. Estimating the age of Calliphora vicina eggs (Diptera: Calliphoridae): determination of embryonic morphological landmarks and preservation of egg samples. Int J Legal Med 2016; 130:845-54. [PMID: 26753872 PMCID: PMC4830879 DOI: 10.1007/s00414-015-1308-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/15/2015] [Indexed: 10/31/2022]
Abstract
Blow fly eggs may sometimes be the only entomological evidence recovered in a forensic case, especially in cooler weather when hatching might take several days: hence, a method for estimating their age is greatly needed. However, developmental data on blow fly eggs are mainly limited to records of the time to larval hatching. The current paper describes the morphological changes occurring during embryogenesis of the blow fly Calliphora vicina Robineau-Desvoidy and their timing in relation to temperature, in order to determine those characters which can be used for simple egg age estimation using light microscopy. At 7.3 and 25 °C, 15 easily visualised morphological landmarks were determined in C. vicina living embryos, allowing for their age estimation with a resolution of 10-20% of total egg developmental time. The observed age intervals were compared to the embryonic stages described for the fruit fly Drosophila melanogaster Meigen, which are used as reference data in multiple developmental studies. Moreover, current guidelines for preservation of egg samples, which recommend the placement of living eggs directly into 80% ethanol, were tested against the hot water killing (HWK) method prior to preservation in 80% ethanol, recommended for larval and pupal specimens. Direct placement of eggs into 80% ethanol caused marked decomposition of samples, and no morphological landmarks were discernible. On the other hand, HWK fixation prior to preservation in 80% ethanol enabled visualisation of 11 of the 15 age-specific morphological landmarks that were discernible in living embryos. Therefore, HWK fixation prior to preservation in 80% ethanol is recommended for egg samples, thus unifying the protocols for collecting entomological evidence.
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7
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Sze SH, Dunham JP, Carey B, Chang PL, Li F, Edman RM, Fjeldsted C, Scott MJ, Nuzhdin SV, Tarone AM. A de novo transcriptome assembly of Lucilia sericata (Diptera: Calliphoridae) with predicted alternative splices, single nucleotide polymorphisms and transcript expression estimates. INSECT MOLECULAR BIOLOGY 2012; 21:205-221. [PMID: 22283785 DOI: 10.1111/j.1365-2583.2011.01127.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The blow fly Lucilia sericata (Diptera: Calliphoridae) (Meigen) is a nonmodel organism with no reference genome that is associated with numerous areas of research spanning the ecological, evolutionary, medical, veterinary and forensic sciences. To facilitate scientific discovery in this species, the transcriptome was assembled from more than six billion bases of Illumina and twenty-one million bases of 454 sequence derived from embryonic, larval, pupal, adult and larval salivary gland libraries. The assembly was carried out in a manner that enabled identification of putative single nucleotide polymorphisms (SNPs) and alternative splices, and that provided expression estimates for various life history stages and for salivary tissue. The assembled transcriptome was also used to identify transcribed transposable elements in L. sericata. The results of this study will enable blow fly biologists, dipterists and comparative genomicists to more rapidly develop and test molecular and genetic hypotheses, especially those regarding blow fly development and salivary gland biology.
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Affiliation(s)
- S-H Sze
- Department of Computer Science and Engineering, Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
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8
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Blechert O, Douglas D, Baumgartner S. Conserved function of the Krüppel gap gene in the blowfly Lucilia sericata, despite anterior shift of expression. INSECT MOLECULAR BIOLOGY 2011; 20:257-265. [PMID: 21166911 DOI: 10.1111/j.1365-2583.2010.01063.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
To determine whether expression patterns of segmentation genes found in Drosophila melanogaster can be scaled to pattern larger insects, we studied the expression of the Krüppel (Kr) gene in the blowfly Lucilia sericata. Compared with Drosophila Kr, L. sericata Kr showed an unexpected 10% shift of expression towards the anterior pole. Furthermore, expression domains not found in D. melanogaster were present at the blastoderm stage of L. sericata. To compare Kr activity and function, we employed RNA interference-mediated gene silencing. We found Kr phenotypes in L. sericata comparable with those observed in D. melanogaster, demonstrating that L. sericata Kr functions as a gap gene as it does in Drosophila. Our results show that, despite an anterior shift in expression, Kr function has remained conserved during the evolution of the blowflies.
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Affiliation(s)
- O Blechert
- Lund University, Department of Experimental Medical Sciences, Lund, Sweden
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9
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Concha C, Belikoff EJ, Carey BL, Li F, Schiemann AH, Scott MJ. Efficient germ-line transformation of the economically important pest species Lucilia cuprina and Lucilia sericata (Diptera, Calliphoridae). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2011; 41:70-75. [PMID: 20869440 DOI: 10.1016/j.ibmb.2010.09.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 08/03/2010] [Accepted: 09/14/2010] [Indexed: 05/29/2023]
Abstract
The green blowfly species Lucilia cuprina and Lucilia sericata are economically important pests for the sheep industries of Australia and New Zealand. L. cuprina has long been considered a good target for a genetic pest management program. In addition, L. sericata maggots are used in the cleaning of wounds and necrotic tissue of patients suffering from ulcers that are difficult to treat by other methods. Development of efficient transgenesis methods would greatly facilitate the development of strains ideal for genetic control programs or could potentially improve "maggot therapy". We have previously reported the germ-line transformation of L. cuprina and the design of a "female killing system" that could potentially be applied to this species. However, the efficiency of transformation obtained was low and transformed lines were difficult to detect due to the low expression of the EGFP marker used. Here we describe an efficient and reliable method for germ-line transformation of L. cuprina using new piggyBac vector and helper plasmids containing the strong promoter from the L. cuprina hsp83 gene to drive expression of the transposase and fluorescent protein marker gene. We also report, for the first time, the germ-line transformation of L. sericata using the new piggyBac vector/helper combination.
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Affiliation(s)
- Carolina Concha
- Institute of Molecular BioSciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
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Tarone AM, Foran DR. Gene expression during blow fly development: improving the precision of age estimates in forensic entomology. J Forensic Sci 2010; 56 Suppl 1:S112-22. [PMID: 21155802 DOI: 10.1111/j.1556-4029.2010.01632.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Forensic entomologists use size and developmental stage to estimate blow fly age, and from those, a postmortem interval. Since such estimates are generally accurate but often lack precision, particularly in the older developmental stages, alternative aging methods would be advantageous. Presented here is a means of incorporating developmentally regulated gene expression levels into traditional stage and size data, with a goal of more precisely estimating developmental age of immature Lucilia sericata. Generalized additive models of development showed improved statistical support compared to models that did not include gene expression data, resulting in an increase in estimate precision, especially for postfeeding third instars and pupae. The models were then used to make blind estimates of development for 86 immature L. sericata raised on rat carcasses. Overall, inclusion of gene expression data resulted in increased precision in aging blow flies.
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Affiliation(s)
- Aaron M Tarone
- Department of Zoology, Michigan State University, East Lansing, 48824, USA
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11
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Hedgehog signaling pathway function conserved in Tribolium segmentation. Dev Genes Evol 2008; 218:181-92. [PMID: 18392879 PMCID: PMC2292471 DOI: 10.1007/s00427-008-0207-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Accepted: 01/22/2008] [Indexed: 01/28/2023]
Abstract
In Drosophila, maintenance of parasegmental boundaries and formation of segmental grooves depend on interactions between segment polarity genes. Wingless and Engrailed appear to have similar roles in both short and long germ segmentation, but relatively little is known about the extent to which Hedgehog signaling is conserved. In a companion study to the Tribolium genome project, we analyzed the expression and function of hedgehog, smoothened, patched, and cubitus interruptus orthologs during segmentation in Tribolium. Their expression was largely conserved between Drosophila and Tribolium. Parental RNAi analysis of positive regulators of the pathway (Tc-hh, Tc-smo, or Tc-ci) resulted in small spherical cuticles with little or no evidence of segmental grooves. Segmental Engrailed expression in these embryos was initiated but not maintained. Wingless-independent Engrailed expression in the CNS was maintained and became highly compacted during germ band retraction, providing evidence that derivatives from every segment were present in these small spherical embryos. On the other hand, RNAi analysis of a negative regulator (Tc-ptc) resulted in embryos with ectopic segmental grooves visible during germband elongation but not discernible in the first instar larval cuticles. These transient grooves formed adjacent to Engrailed expressing cells that encircled wider than normal wg domains in the Tc-ptc RNAi embryos. These results suggest that the en–wg–hh gene circuit is functionally conserved in the maintenance of segmental boundaries during germ band retraction and groove formation in Tribolium and that the segment polarity genes form a robust genetic regulatory module in the segmentation of this short germ insect.
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12
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Simpson P. The stars and stripes of animal bodies: evolution of regulatory elements mediating pigment and bristle patterns in Drosophila. Trends Genet 2007; 23:350-8. [PMID: 17499383 DOI: 10.1016/j.tig.2007.04.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 04/11/2007] [Accepted: 04/23/2007] [Indexed: 11/22/2022]
Abstract
Evolution has generated enormous morphological diversity in animals and one of the genetic processes that might have contributed to this is evolution of the cis-regulatory sequences responsible for the temporal and spatial expression of genes regulating embryonic development. This could be particularly relevant to pleiotropic genes with multiple independently acting regulatory modules. Loss or gain of modules enables altered expression without loss of other functions. Here I focus on recent studies correlating differences in morphological traits between related species of Drosophila to changes in cis-regulatory sequences. They show that ancestral regulatory modules have evolved to mediate different transcriptional outputs and suggest that evolution of cis-regulatory sequences might reflect a general mechanism driving evolutionary change.
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Affiliation(s)
- Pat Simpson
- Department of Zoology, University of Cambridge, Cambridge, UK.
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13
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Ali RA, Mellenthin K, Fahmy K, Da Rocha S, Baumgartner S. Structural conservation of the salivary gland-specific slalom gene in the blowfly Lucilia sericata. Dev Genes Evol 2005; 215:537-43. [PMID: 16003524 DOI: 10.1007/s00427-005-0010-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Accepted: 05/20/2005] [Indexed: 10/25/2022]
Abstract
Glycosylation and sulfation are two of the essential post-translational modifications of proteins. The slalom gene encodes a 3'-phosphoadenosine 5'-phosphosulfate transporter, a conserved protein found in organisms as diverse as plants and humans and required for sulfation of proteins. In Drosophila, slalom is exclusively expressed in salivary glands, which is unexpected, taken into account the general function for sulfation of proteins. In this paper, we present a detailed description of the slalom gene in a large insect, the blowfly Lucilia sericata. Our data demonstrate that the slalom gene structure, the protein and the expression pattern are highly conserved between Lucilia and Drosophila. Lucilia slalom promoter analysis, using transgenic Drosophila, demonstrates that the Lucilia slalom promoter can faithfully mimic the expression pattern of both Lucilia and Drosophila slalom in salivary glands. Taken together, these data show the structure and the transcriptional cis-regulatory elements of the slalom gene to be unchanged during evolution, despite the 100 million years of divergence between the two insects. Moreover, it suggests that the salivary gland-specific expression of slalom bears an important and conserved function for sulfation of specific macromolecules.
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Affiliation(s)
- Reda A Ali
- Department of Experimental Medical Science, Lund University, BMC B13, 22184 Lund, Sweden
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