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Krasovec G, Renaud C, Quéinnec É, Sasakura Y, Chambon JP. Extrinsic apoptosis participates to tail regression during the metamorphosis of the chordate Ciona. Sci Rep 2024; 14:5729. [PMID: 38459045 PMCID: PMC10923776 DOI: 10.1038/s41598-023-48411-y] [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: 05/24/2023] [Accepted: 11/26/2023] [Indexed: 03/10/2024] Open
Abstract
Apoptosis is a regulated cell death ubiquitous in animals defined by morphological features depending on caspases. Two regulation pathways are described, currently named the intrinsic and the extrinsic apoptosis. While intrinsic apoptosis is well studied and considered ancestral among metazoans, extrinsic apoptosis is poorly studied outside mammals. Here, we address extrinsic apoptosis in the urochordates Ciona, belonging to the sister group of vertebrates. During metamorphosis, Ciona larvae undergo a tail regression depending on tissue contraction, migration and apoptosis. Apoptosis begin at the tail tip and propagates towards the trunk as a polarized wave. We identified Ci-caspase 8/10 by phylogenetic analysis as homolog to vertebrate caspases 8 and 10 that are the specific initiator of extrinsic apoptosis. We detected Ci-caspase 8/10 expression in Ciona larvae, especially at the tail tip. We showed that chemical inhibition of Ci-caspase 8/10 leads to a delay of tail regression, and Ci-caspase 8/10 loss of function induced an incomplete tail regression. The specificity between apoptotic pathways and initiator caspase suggests that extrinsic apoptosis regulates cell death during the tail regression. Our study presents rare in vivo work on extrinsic apoptosis outside mammals, and contribute to the discussion on its evolutionary history in animals.
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Affiliation(s)
- Gabriel Krasovec
- Institut de Systématique, Evolution, Biodiversité, Sorbonne Université, Muséum National d'Histoire Naturelle, CNRS, EPHE, F-75252, Paris Cedex 05, France.
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan.
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France.
| | - Cécile Renaud
- Institut de Systématique, Evolution, Biodiversité, Sorbonne Université, Muséum National d'Histoire Naturelle, CNRS, EPHE, F-75252, Paris Cedex 05, France
| | - Éric Quéinnec
- Institut de Systématique, Evolution, Biodiversité, Sorbonne Université, Muséum National d'Histoire Naturelle, CNRS, EPHE, F-75252, Paris Cedex 05, France
| | - Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
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Jeffery WR, Gorički Š. Apoptosis is a generator of Wnt-dependent regeneration and homeostatic cell renewal in the ascidian Ciona. Biol Open 2021; 10:258582. [PMID: 33913473 PMCID: PMC8084579 DOI: 10.1242/bio.058526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/29/2021] [Indexed: 12/21/2022] Open
Abstract
In the ascidian Ciona intestinalis, basal body parts regenerate distal structures but distal body parts do not replace basal structures. Regeneration involves the activity of adult stem cells in the branchial sac, which proliferate and produce migratory progenitor cells for tissue and organ replacement. Branchial sac-derived stem cells also replenish recycling cells lining the pharyngeal fissures during homeostatic growth. Apoptosis at injury sites occurs early during regeneration and continuously in the pharyngeal fissures during homeostatic growth. Caspase 1 inhibitor, caspase 3 inhibitor, or pan-caspase inhibitor Z-VAD-FMK treatment blocked apoptosis, prevented regeneration, and suppressed branchial sac growth and function. A pharmacological screen and siRNA-mediated gene knockdown indicated that regeneration requires canonical Wnt signaling. Wnt3a protein rescued both caspase-blocked regeneration and branchial sac growth. Inhibition of apoptosis did not affect branchial sac stem cell proliferation but prevented the survival of progenitor cells. After bisection across the mid-body, apoptosis occurred only in the regenerating basal fragments, although both fragments contained a part of the branchial sac, suggesting that apoptosis is unilateral at the wound site and the presence of branchial sac stem cells is insufficient for regeneration. The results suggest that apoptosis-dependent Wnt signaling mediates regeneration and homeostatic growth in Ciona. Summary: Apoptosis induces Wnt-dependent regeneration and homeostatic cell renewal in Ciona. Apoptosis is required for stem cell survival and is absent in non-regenerating body parts, suggesting a role in asymmetrical regeneration.
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Affiliation(s)
- William R Jeffery
- Department of Biology, University of Maryland, College Park, MD 20742, USA.,Station Biologique, Roscoff 29680, France
| | - Špela Gorički
- Station Biologique, Roscoff 29680, France.,Scriptorium Biologorum LLC, Murska Sobota 9000, Slovenia
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3
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Krasovec G, Robine K, Quéinnec E, Karaiskou A, Chambon J. Ci-hox12 tail gradient precedes and participates in the control of the apoptotic-dependent tail regression during Ciona larva metamorphosis. Dev Biol 2019; 448:237-246. [DOI: 10.1016/j.ydbio.2018.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 12/11/2018] [Accepted: 12/11/2018] [Indexed: 01/20/2023]
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4
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Tassia MG, Whelan NV, Halanych KM. Toll-like receptor pathway evolution in deuterostomes. Proc Natl Acad Sci U S A 2017; 114:7055-7060. [PMID: 28630328 PMCID: PMC5502590 DOI: 10.1073/pnas.1617722114] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Animals have evolved an array of pattern-recognition receptor families essential for recognizing conserved molecular motifs characteristic of pathogenic microbes. One such family is the Toll-like receptors (TLRs). On pathogen binding, TLRs initiate specialized cytokine signaling catered to the class of invading pathogen. This signaling is pivotal for activating adaptive immunity in vertebrates, suggesting a close evolutionary relationship between innate and adaptive immune systems. Despite significant advances toward understanding TLR-facilitated immunity in vertebrates, knowledge of TLR pathway evolution in other deuterostomes is limited. By analyzing genomes and transcriptomes across 37 deuterostome taxa, we shed light on the evolution and diversity of TLR pathway signaling elements. Here, we show that the deuterostome ancestor possessed a molecular toolkit homologous to that which drives canonical MYD88-dependent TLR signaling in contemporary mammalian lineages. We also provide evidence that TLR3-facilitated antiviral signaling predates the origin of its TCAM1 dependence recognized in the vertebrates. SARM1, a negative regulator of TCAM1-dependent pathways in vertebrates, was also found to be present across all major deuterostome lineages despite the apparent absence of TCAM1 in invertebrate deuterostomes. Whether the presence of SARM1 is the result of its role in immunity regulation, neuron physiology, or a function of both is unclear. Additionally, Bayesian phylogenetic analyses corroborate several lineage-specific TLR gene expansions in urchins and cephalochordates. Importantly, our results underscore the need to sample across taxonomic groups to understand evolutionary patterns of the innate immunity foundation on which complex immunological novelties arose.
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Affiliation(s)
- Michael G Tassia
- Department of Biological Sciences, Auburn University, Auburn, AL 36849;
| | - Nathan V Whelan
- Department of Biological Sciences, Auburn University, Auburn, AL 36849
- Warm Springs Fish Technology Center, US Fish and Wildlife Service, Warm Springs, GA 31830
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Aouacheria A, Le Goff E, Godefroy N, Baghdiguian S. Evolution of the BCL-2-Regulated Apoptotic Pathway. Evol Biol 2016. [PMCID: PMC7123326 DOI: 10.1007/978-3-319-41324-2_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The mitochondrion descends from a bacterium that, about two billion years ago, became endosymbiotic. This organelle represents a Pandora’s box whose opening triggers cytochrome-c release and apoptosis of cells from multicellular animals, which evolved much later, about six hundred million years ago. BCL-2 proteins, which are critical apoptosis regulators, were recruited at a certain time point in evolution to either lock or unlock this mitochondrial Pandora’s box. Hence, particularly intriguing is the issue of when and how the “BCL-2 proteins–mitochondria–apoptosis” triptych emerged. This chapter explains what it takes from an evolutionary perspective to evolve a BCL-2-regulated apoptotic pathway, by focusing on the events occurring upstream of mitochondria.
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Sakamaki K, Iwabe N, Iwata H, Imai K, Takagi C, Chiba K, Shukunami C, Tomii K, Ueno N. Conservation of structure and function in vertebrate c-FLIP proteins despite rapid evolutionary change. Biochem Biophys Rep 2015; 3:175-189. [PMID: 29124180 PMCID: PMC5668880 DOI: 10.1016/j.bbrep.2015.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 08/05/2015] [Accepted: 08/05/2015] [Indexed: 12/26/2022] Open
Abstract
Cellular FLICE-like inhibitory protein (c-FLIP, gene symbol CFLAR) was first identified as a negative regulator of death receptor-mediated apoptosis in mammals. To understand the ubiquity and diversity of the c-FLIP protein subfamily during evolution, c-FLIP orthologs were identified from a comprehensive range of vertebrates, including birds, amphibians, and fish, and were characterized by combining experimental and computational analysis. Predictions of three-dimensional protein structures and molecular phylogenetic analysis indicated that the conserved structural features of c-FLIP proteins are all derived from an ancestral caspase-8, although they rapidly diverged from the subfamily consisting of caspases-8, -10, and -18. The functional role of the c-FLIP subfamily members is nearly ubiquitous throughout vertebrates. Exogenous expression of non-mammalian c-FLIP proteins in cultured mammalian cells suppressed death receptor-mediated apoptosis, implying that all of these proteins possess anti-apoptotic activity. Furthermore, non-mammalian c-FLIP proteins induced NF-κB activation much like their mammalian counterparts. The CFLAR mRNAs were synthesized during frog and fish embryogenesis. Overexpression of a truncated mutant of c-FLIP in the Xenopus laevis embryos by mRNA microinjection caused thorax edema and abnormal constriction of the abdomen. Depletion of cflar transcripts in zebrafish resulted in developmental abnormalities accompanied by edema and irregular red blood cell flow. Thus, our results demonstrate that c-FLIP/CFLAR is conserved in both protein structure and function in several vertebrate species, and suggest a significant role of c-FLIP in embryonic development.
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Key Words
- Apoptosis
- CARD, caspase-recruitment domain
- CASc, Caspase, interleukin-1 β converting enzyme homologs
- CHX, cycloheximide
- Caspase-8
- DED, death effector domain
- EGFP, enhanced green fluorescent protein
- Embryogenesis
- Evolution
- FADD, Fas-associated death domain protein
- MO, morpholino oligonucleotide
- NF-κB
- NF-κB, Nuclear factor-kappa B
- ODC, ornithine decarboxylase
- PCR, polymerase chain reaction
- Pseudocatalytic triad
- RT-PCR, reverse transcription-polymerase chain reaction
- TRAF2, tumor necrosis factor receptor-associated factor 2
- c-FLIP, cellular FLICE-like inhibitory protein
- tubα6, tubulin α6
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Affiliation(s)
- Kazuhiro Sakamaki
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Naoyuki Iwabe
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Hiroaki Iwata
- Multi-scale Research Center for Medical Science, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan
| | - Kenichiro Imai
- Biotechnology Research Institute for Drug Discovery, Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064, Japan
| | - Chiyo Takagi
- Department of Developmental Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan
| | - Kumiko Chiba
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Chisa Shukunami
- Department of Cellular Differentiation, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
| | - Kentaro Tomii
- Biotechnology Research Institute for Drug Discovery, Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064, Japan
| | - Naoto Ueno
- Department of Developmental Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan
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Karaiskou A, Swalla BJ, Sasakura Y, Chambon JP. Metamorphosis in solitary ascidians. Genesis 2014; 53:34-47. [PMID: 25250532 DOI: 10.1002/dvg.22824] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/15/2014] [Accepted: 09/19/2014] [Indexed: 12/19/2022]
Abstract
Embryonic and postembryonic development in ascidians have been studied for over a century, but it is only in the last 10 years that the complex molecular network involved in coordinating postlarval development and metamorphosis has started to emerge. In most ascidians, the transition from the larval to the sessile juvenile/adult stage, or metamorphosis, requires a combination of environmental and endogenous signals and is characterized by coordinated global morphogenetic changes that are initiated by the adhesion of the larvae. Cloney was the first to describe cellular events of ascidians' metamorphosis in 1978 and only recently elements of the molecular regulation of this crucial developmental step have been revealed. This review aims to present a thorough view of this crucial developmental step by combining recent molecular data to the already established cellular events.
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Affiliation(s)
- Anthi Karaiskou
- Sorbonne Universités, UPMC Univ Paris 06, UMR7622-Biologie du Développement, Paris, France
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8
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Dishaw LJ, Flores-Torres JA, Mueller MG, Karrer CR, Skapura DP, Melillo D, Zucchetti I, De Santis R, Pinto MR, Litman GW. A Basal chordate model for studies of gut microbial immune interactions. Front Immunol 2012; 3:96. [PMID: 22563328 PMCID: PMC3342567 DOI: 10.3389/fimmu.2012.00096] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 04/12/2012] [Indexed: 12/23/2022] Open
Abstract
Complex symbiotic interactions at the surface of host epithelia govern most encounters between host and microbe. The epithelium of the gut is a physiologically ancient structure that is comprised of a single layer of cells and is thought to possess fully developed immunological capabilities. Ciona intestinalis (sea squirt), which is a descendant of the last common ancestor of all vertebrates, is a potentially valuable model for studying barrier defenses and gut microbial immune interactions. A variety of innate immunological phenomena have been well characterized in Ciona, of which many are active in the gut tissues. Interactions with gut microbiota likely involve surface epithelium, secreted immune molecules including variable region-containing chitin-binding proteins, and hemocytes from a densely populated laminar tissue space. The microbial composition of representative gut luminal contents has been characterized by molecular screening and a potentially relevant, reproducible, dysbiosis can be induced via starvation. The dialog between host and microbe in the gut can be investigated in Ciona against the background of a competent innate immune system and in the absence of the integral elements and processes that are characteristic of vertebrate adaptive immunity.
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Affiliation(s)
- Larry J Dishaw
- Department of Pediatrics, USF/ACH Children's Research Institute, University of South Florida College of Medicine St. Petersburg, FL, USA
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9
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Weill M, Philips A, Chourrout D, Fort P. The caspase family in urochordates: distinct evolutionary fates in ascidians and larvaceans. Biol Cell 2012; 97:857-66. [PMID: 15826240 DOI: 10.1042/bc20050018] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND INFORMATION Caspases are cysteine proteases that mediate apoptosis (programmed cell death) initiation and execution. Apoptosis is a conserved mechanism shared by all metazoans, although its physiological function and complexity show considerable taxon-dependent variations. To gain insight into the caspase repertoire of putative ancestors to vertebrates, we performed exhaustive genomic searches in urochordates, a sister taxon to vertebrates in which ascidians and appendicularians display chordate characters at early stages of their development. RESULTS We identified the complete caspase families of two ascidians (Ciona intestinalis and C. savignyi) and one larvacean (Oikopleura dioica). We found in ascidian species an extremely high number of caspase genes (17 for C. intestinalis and 22 for C. savignyi), deriving from five founder gene orthologues to human pro-inflammatory, initiator and executioner caspases. Although considered to be sibling species, C. intestinalis and C. savignyi only share 11 orthologues, most of the additional genes resulting from recent mass duplications. A sharply contrasted picture was found in O. dioica, which displayed only three caspase genes deriving from a single founder gene distantly related to caspase 3/7. The difference between ascidian and larvacean caspase repertoires is discussed in the light of their developmental patterns and life cycles. CONCLUSIONS The identification of caspase members in two ascidian species delineates five founder genes that bridge the gap between vertebrates and Ecdysozoa (arthropods and nematodes). Given the amazing diversity among urochordates, determination and comparison of the caspase repertoires in species from orders additional to Enterogona (ascidians) and Oikopleuridae might be highly informative on the evolution of caspase-dependent physiological processes.
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Affiliation(s)
- Mylène Weill
- Institut des Sciences de l'Evolution (UMR 5554), C.C. 065, Univ. Montpellier II, 34095 Montpellier cedex 5, France
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10
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Parrinello N, Vizzini A, Salerno G, Sanfratello MA, Cammarata M, Arizza V, Vazzana M, Parrinello D. Inflamed adult pharynx tissues and swimming larva of Ciona intestinalis share CiTNFα-producing cells. Cell Tissue Res 2010; 341:299-311. [DOI: 10.1007/s00441-010-0993-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 05/06/2010] [Indexed: 12/14/2022]
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11
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Cima F, Manni L, Basso G, Fortunato E, Accordi B, Schiavon F, Ballarin L. Hovering between death and life: natural apoptosis and phagocytes in the blastogenetic cycle of the colonial ascidian Botryllus schlosseri. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2010; 34:272-285. [PMID: 19837108 DOI: 10.1016/j.dci.2009.10.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Revised: 10/06/2009] [Accepted: 10/09/2009] [Indexed: 05/28/2023]
Abstract
Colonies of the compound ascidian Botryllus schlosseri undergo recurrent generation changes during which massive, natural apoptosis occurs in zooid tissues: for this reason the species is emerging as an interesting model of invertebrate chordate, phylogenetically related to vertebrates, for studies of apoptosis during development. In the present work, we carried out a series of morphological, cytofluorimetrical and biochemical analyses, useful for a better characterization of Botryllus apoptosis. Results are consistent with the following viewpoints: (i) both intrinsic and extrinsic pathways, probably connected by the BH3-only protein Bid, are involved in cell death induction; (ii) phagocytes, once loaded with senescent cells, frequently undergo apoptosis, probably as a consequence of oxidative stress caused by prolonged respiratory burst, and (iii) senescent phagocytes are easily recognized and ingested by other phagocytes, responsible for their clearance. In addition, results suggest the conservation of apoptosis induction mechanisms throughout chordate evolution.
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Affiliation(s)
- Francesca Cima
- Department of Biology, University of Padova, Padova, Italy
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12
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Sakamaki K, Satou Y. Caspases: evolutionary aspects of their functions in vertebrates. JOURNAL OF FISH BIOLOGY 2009; 74:727-53. [PMID: 20735596 PMCID: PMC2779465 DOI: 10.1111/j.1095-8649.2009.02184.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Caspases (cysteine-dependent aspartyl-specific protease) belong to a family of cysteine proteases that mediate proteolytic events indispensable for biological phenomena such as cell death and inflammation. The first caspase was identified as an executioner of apoptotic cell death in the worm Caenorhabditis elegans. Additionally, a large number of caspases have been identified in various animals from sponges to vertebrates. Caspases are thought to play a pivotal role in apoptosis as an evolutionarily conserved function; however, the number of caspases that can be identified is distinct for each species. This indicates that species-specific functions or diversification of physiological roles has been cultivated through caspase evolution. Furthermore, recent studies suggest that caspases are also involved in inflammation and cellular differentiation in mammals. This review highlights vertebrate caspases in their universal and divergent functions and provides insight into the physiological roles of these molecules in animals.
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Affiliation(s)
- K Sakamaki
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
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13
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Martinand-Mari C, Maury B, Rousset F, Sahuquet A, Mennessier G, Rochal S, Lorman V, Mangeat P, Baghdiguian S. Topological control of life and death in non-proliferative epithelia. PLoS One 2009; 4:e4202. [PMID: 19145253 PMCID: PMC2625397 DOI: 10.1371/journal.pone.0004202] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Accepted: 12/08/2008] [Indexed: 11/26/2022] Open
Abstract
Programmed cell death is one of the most fascinating demonstrations of the plasticity of biological systems. It is classically described to act upstream of and govern major developmental patterning processes (e.g. inter-digitations in vertebrates, ommatidia in Drosophila). We show here the first evidence that massive apoptosis can also be controlled and coordinated by a pre-established pattern of a specific ‘master cell’ population. This new concept is supported by the development and validation of an original model of cell patterning. Ciona intestinalis eggs are surrounded by a three-layered follicular organization composed of 60 elongated floating extensions made of as many outer and inner cells, and indirectly spread through an extracellular matrix over 1200 test cells. Experimental and selective ablation of outer and inner cells results in the abrogation of apoptosis in respective remaining neighbouring test cells. In addition incubation of outer/inner follicular cell-depleted eggs with a soluble extract of apoptotic outer/inner cells partially restores apoptosis to apoptotic-defective test cells. The 60 inner follicular cells were thus identified as ‘apoptotic master’ cells which collectively are induction sites for programmed cell death of the underlying test cells. The position of apoptotic master cells is controlled by topological constraints exhibiting a tetrahedral symmetry, and each cell spreads over and can control the destiny of 20 smaller test cells, which leads to optimized apoptosis signalling.
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Affiliation(s)
- Camille Martinand-Mari
- Université Montpellier 2, UMR CNRS 5554, Institut des Sciences de l'Evolution, Montpellier, France
| | - Benoit Maury
- Université Montpellier 2, UMR CNRS 5554, Institut des Sciences de l'Evolution, Montpellier, France
| | - François Rousset
- Université Montpellier 2, UMR CNRS 5554, Institut des Sciences de l'Evolution, Montpellier, France
| | - Alain Sahuquet
- Université Montpellier 2, CRBM UMR CNRS 5237, Montpellier, France
| | | | - Sergei Rochal
- South Federal University, Faculty of Physics, Rostov na Donu, Russia
| | - Vladimir Lorman
- Université Montpellier 2, UMR CNRS 5207-LPTA, Montpellier, France
| | - Paul Mangeat
- Université Montpellier 2, CRBM UMR CNRS 5237, Montpellier, France
| | - Stephen Baghdiguian
- Université Montpellier 2, UMR CNRS 5554, Institut des Sciences de l'Evolution, Montpellier, France
- * E-mail:
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14
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Menin A, Ballarin L. Immunomodulatory molecules in the compound ascidian Botryllus schlosseri: Evidence from conditioned media. J Invertebr Pathol 2008; 99:275-80. [DOI: 10.1016/j.jip.2008.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Revised: 08/06/2008] [Accepted: 08/11/2008] [Indexed: 11/30/2022]
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15
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Cao L, Wang Z, Yang X, Xie L, Yu L. The evolution of BIR domain and its containing proteins. FEBS Lett 2008; 582:3817-22. [PMID: 18948100 DOI: 10.1016/j.febslet.2008.09.058] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Revised: 09/20/2008] [Accepted: 09/24/2008] [Indexed: 10/21/2022]
Abstract
BIR domain and its containing proteins play critical roles in cell apoptosis and cell division. Here several lines of novelty were revealed based on a comprehensive evolutionary analysis of BIR domains in 11 representative organisms. First, the type II BIR domains in Survivin and Bruce showed more conservation compared with the type I BIR domains in the inhibitors of apoptosis proteins (IAPs). Second, cIAP was derived from a XIAP duplicate and emerged just after the divergence of invertebrates and vertebrates. Third, the three BIR domains of NAIP displayed significantly elevated evolutionary rates compared with the BIR domains in other IAPs.
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Affiliation(s)
- Lihuan Cao
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai 200433, PR China
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16
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Enhanced expression of a cloned and sequenced Ciona intestinalis TNFα-like (CiTNFα) gene during the LPS-induced inflammatory response. Cell Tissue Res 2008; 334:305-17. [DOI: 10.1007/s00441-008-0695-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Accepted: 09/04/2008] [Indexed: 10/21/2022]
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17
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Zhang X, Luan W, Jin S, Xiang J. A novel tumor necrosis factor ligand superfamily member (CsTL) from Ciona savignyi: molecular identification and expression analysis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2008; 32:1362-1373. [PMID: 18579203 DOI: 10.1016/j.dci.2008.05.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Revised: 05/04/2008] [Accepted: 05/06/2008] [Indexed: 05/26/2023]
Abstract
A novel invertebrate TNF ligand was identified and characterized in Ciona savignyi. The CsTL cDNA consisted of 995 nucleotides and encoded 281 amino acids. A conserved TNF family signature and several motifs of TNF ligand superfamily were identified in deduced amino acid sequence of CsTL. Phylogenetic analysis grouped CsTL, CiTNF (predicted TNF ligand superfamily homolog in Ciona intestinalis) and urchin TL1A with their own cluster apart from mammalian TNFalpha, LTA, TNFSF15 and fish TNFalpha proteins. Expression studies demonstrated that CsTL mRNA is present in all tested tissues from unchallenged ascidians and its expression was significantly upregulated in hemocytes following LPS injection. The recombinant CsTL protein expressed using a baculovirus expression system showed potential cytotoxic activity in L929 cells. Present results indicated that TNF ligand superfamily molecules are present in marine invertebrates.
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Affiliation(s)
- Xiaoming Zhang
- Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, PR China
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Takada N, Yamaguchi H, Shida K, Terajima D, Satou Y, Kasuya A, Satoh N, Satake M, Wang HG. The cell death machinery controlled by Bax and Bcl-XL is evolutionarily conserved in Ciona intestinalis. Apoptosis 2008; 10:1211-20. [PMID: 16215691 DOI: 10.1007/s10495-005-1391-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Bax and Bcl-XL are key regulators of apoptosis in mammals. Here we report the functional characterization of two Bcl-2 homologues, ciBax and ciBcl-XL, in a basal invertebrate-chordate ascidian Ciona intestinalis. CiBax is a Ciona homologue of the BH1-3 pro-apoptotic protein Bax, whereas ciBcl-XL is a Bcl-XL-like anti-apoptotic protein. Molecular modeling analysis showed that ciBax and ciBcl-XL share both sequence and structural similarities to human Bax and Bcl-XL, respectively. Like their human counterparts, ciBax could form a homodimer or oligomers as well as heterodimerize with ciBcl-XL, and overexpression of ciBax caused apoptosis that could be attenuated by ciBcl-XL. Mutagenesis studies showed that the BH3 domain of ciBax is critical for its cell death-inducing function and also for its interaction with ciBcl-XL. In Ciona embryos, ectopic expression of ciBax but not its BH3 deletion mutant resulted in cell dissociation and apoptosis after late gastrula stage of embryonic development. Moreover, not only wild type ciBcl-XL but also a mutant ciBcl-XL(F101V), which is unable to interact with ciBax, could block cell dissociation and developmental deficit in Ciona embryos induced by overexpression of ciBax. Taken together, these findings suggest that functional homologues of both the BH1-3 death effector Bax and the pro-survival Bcl-XL exist in sea squirt Ciona intestinalis, and they control the cell death machinery independent of their heterodimerization.
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Affiliation(s)
- N Takada
- Department of Interdisciplinary Oncology, Drug Discovery Program, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, 12902 Magnolia Drive, Tampa, FL 33612, USA
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19
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Ballarin L, Menin A, Tallandini L, Matozzo V, Burighel P, Basso G, Fortunato E, Cima F. Haemocytes and blastogenetic cycle in the colonial ascidian Botryllus schlosseri: a matter of life and death. Cell Tissue Res 2007; 331:555-64. [PMID: 17972103 DOI: 10.1007/s00441-007-0513-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Accepted: 09/12/2007] [Indexed: 10/22/2022]
Abstract
A recurrent blastogenetic cycle characterizes colonies of the ascidian Botryllus schlosseri. This cycle starts when a new zooid generation opens its siphons and ends with take-over, when adult zooids cease filtering and are progressively resorbed and replaced by a new generation of buds, reaching functional maturity. During the generation change, massive apoptosis occurs in the colony, mainly in the tissues of old zooids. In the present study, we have investigated the behaviour of haemocytes during the colonial blastogenetic cycle, in terms of the occurrence of cell death and the expression of molecules involved in the induction of apoptosis. Our results indicate that, during take-over, caspase-3 activity in haemocyte lysates increases. In addition, about 20%-30% of haemocytes express phosphatidylserine on the outer leaflet of their plasma membrane, show DNA fragmentation and are immunopositive for caspase-3. Senescent cells are quickly ingested by circulating phagocytes that frequently, having once engulfed effete cells, in turn enter apoptosis. Dying cells and corpses are replaced by a new generation of cells that appear in the circulation during the generation change.
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Affiliation(s)
- Loriano Ballarin
- Department of Biology, University of Padua, Via U. Bassi 58/B, 35100, Padua, Italy.
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20
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Sakamaki K, Nozaki M, Kominami K, Satou Y. The evolutionary conservation of the core components necessary for the extrinsic apoptotic signaling pathway, in Medaka fish. BMC Genomics 2007; 8:141. [PMID: 17540041 PMCID: PMC1903365 DOI: 10.1186/1471-2164-8-141] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Accepted: 06/01/2007] [Indexed: 12/24/2022] Open
Abstract
Background Death receptors on the cell surface and the interacting cytosolic molecules, adaptors and initiator caspases, are essential as core components of the extrinsic apoptotic signaling pathway. While the apoptotic machinery governing the extrinsic signaling pathway is well characterized in mammals, it is not fully understood in fish. Results We identified and characterized orthologs of mammalian Fas, FADD and caspase-8 that correspond to the death receptor, adaptor and initiator caspase, from the Medaka fish (Oryzias latipes). Medaka Fas, caspase-8 and FADD exhibited protein structures similar to that of their mammalian counterparts, containing a death domain (DD), a death effector domain (DED) or both. Functional analyses indicated that these molecules possess killing activity in mammalian cell lines upon overexpression or following activation by apoptotic stimuli, suggesting similar pro-apoptotic functions in the extrinsic pathway as those in mammals. Genomic sequence analysis revealed that the Medaka fas (tnfrsf6), fadd and caspase-8 (casp8) genes are organized in a similar genomic structure as the mammalian genes. Database search and phylogenetic analysis revealed that the fas gene, but not the fadd and casp8 genes, appear to be present only in vertebrates. Conclusion Our results indicate that the core components necessary for the extrinsic apoptotic pathway are evolutionarily conserved in function and structure across vertebrate species. Based on these results, we presume the mechanism of apoptosis induction via death receptors was evolutionarily established during the appearance of vertebrates.
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MESH Headings
- Amino Acid Sequence
- Animals
- Apoptosis
- Base Sequence
- Caspase 8/chemistry
- Caspase 8/genetics
- Caspase 8/metabolism
- Cells, Cultured
- DNA, Complementary
- Databases, Genetic
- Embryo, Mammalian
- Embryo, Nonmammalian
- Evolution, Molecular
- Exons
- Expressed Sequence Tags
- Fas Ligand Protein/chemistry
- Fas Ligand Protein/genetics
- Fas Ligand Protein/metabolism
- Fas-Associated Death Domain Protein/chemistry
- Fas-Associated Death Domain Protein/genetics
- Fas-Associated Death Domain Protein/metabolism
- Fibroblasts/cytology
- Fibroblasts/metabolism
- Fluorescent Antibody Technique, Indirect
- Genome
- HeLa Cells
- Humans
- Immunohistochemistry
- Mice
- Molecular Sequence Data
- NIH 3T3 Cells
- Open Reading Frames
- Oryzias/genetics
- Oryzias/metabolism
- Phylogeny
- Protein Structure, Tertiary
- Receptors, Death Domain/chemistry
- Receptors, Death Domain/genetics
- Receptors, Death Domain/metabolism
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Signal Transduction
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Affiliation(s)
- Kazuhiro Sakamaki
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Masami Nozaki
- Department of Cell Biology, Research Institute for Microbial Diseases, Osaka University, Suita 565-0871, Japan
| | - Katsuya Kominami
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
- Present address: Nihon Schering Research Center, Kobe 650-0047, Japan
| | - Yutaka Satou
- Department of Zoology, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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21
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Baghdiguian S, Martinand-Mari C, Mangeat P. Using Ciona to study developmental programmed cell death. Semin Cancer Biol 2007; 17:147-53. [PMID: 17197195 DOI: 10.1016/j.semcancer.2006.11.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2006] [Accepted: 11/25/2006] [Indexed: 11/22/2022]
Abstract
Ciona intestinalis, a member of Tunicates, the closest group to vertebrates, has emerged as an appropriate organism for the study of developmentally regulated programmed cell death. First, because massive phases of apoptosis occur all along embryogenesis. Second, because the lecithotrophic mode of development is associated with autophagic process occurring during juvenile formation. Third, because the biochemical cell death machinery is close to that found in mammals. Altogether, the Ciona system contributes to identify new specific regulatory pathways and to explain how molecular mechanisms of programmed cell death evolved from invertebrates to vertebrates.
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Affiliation(s)
- Stephen Baghdiguian
- UMR CNRS 5554, Institut des Sciences de l'Evolution, Case Courrier No. 065, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier, Cedex 05, France.
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22
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Sakata SI, Yan Y, Satou Y, Momoi A, Ngo-Hazelett P, Nozaki M, Furutani-Seiki M, Postlethwait JH, Yonehara S, Sakamaki K. Conserved function of caspase-8 in apoptosis during bony fish evolution. Gene 2007; 396:134-48. [PMID: 17459614 PMCID: PMC2064871 DOI: 10.1016/j.gene.2007.03.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2006] [Revised: 02/24/2007] [Accepted: 03/14/2007] [Indexed: 11/19/2022]
Abstract
Caspase-8, a member of the caspase family, plays an important role in apoptotic signal transduction in mammals. Here we report the identification and characterization of the caspase-8 (casp8) gene in the zebrafish Danio rerio. The zebrafish casp8 gene has a genomic organization similar to mammalian casp8 genes, consisting of 10 exons. By chromosome mapping, we found that casp8 maps on linkage group 6 (LG6), a zebrafish chromosome segment orthologous to the long arm of human Chr. 2, which carries CASP8. In contrast, the zebrafish casp10-like gene and the cflar gene separately localize on LG9 and LG11, respectively, and these genes form a cluster with CASP8 on the human chromosome. This chromosomal segregation is unique to fish but not other vertebrates. Furthermore, we examined the function of zebrafish Casp8 protein in mammalian cells, and showed that it has pro-apoptotic activity when overexpressed. In addition, this molecule was capable of transmitting apoptotic signals mediated through not only Fas but also the TNF receptor in mouse Casp8-deficient cells. Expression analysis showed that casp8 is maternally expressed, and transcripts continue to be present throughout embryogenesis and into larval stages. These results show that zebrafish casp8 has a structure and function similar to mammalian CASP8 orthologs, and our study suggests that the role of caspase-8 in the apoptotic signal pathway has been conserved over at least 450 million years of vertebrate evolution.
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Affiliation(s)
- Shin-ichi Sakata
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
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23
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Wada S, Hamada M, Satoh N. A genomewide analysis of genes for the heat shock protein 70 chaperone system in the ascidian Ciona intestinalis. Cell Stress Chaperones 2006; 11:23-33. [PMID: 16572726 PMCID: PMC1400611 DOI: 10.1379/csc-137r.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Molecular chaperones play crucial roles in various aspects of the biogenesis and maintenance of proteins in the cell. The heat shock protein 70 (HSP70) chaperone system, in which HSP70 proteins act as chaperones, is one of the major molecular chaperone systems conserved among a variety of organisms. To shed light on the evolutionary history of the constituents of the chordate HSP70 chaperone system and to identify all of the components of the HSP70 chaperone system in ascidians, we carried out a comprehensive survey for HSP70s and their cochaperones in the genome of Ciona intestinalis. We characterized all members of the Ciona HSP70 superfamily, J-proteins, BAG family, and some other types of cochaperones. The Ciona genome contains 8 members of the HSP70 superfamily, all of which have human and protostome counterparts. Members of the STCH subfamily of the HSP70 family and members of the HSPA14 subfamily of the HSP110 family are conserved between humans and protostomes but were not found in Ciona. The Ciona genome encodes 36 J-proteins, 32 of which belong to groups conserved in humans and protostomes. Three proteins seem to be unique to Ciona. J-proteins of the RBJ group are conserved between humans and Ciona but were not found in protostomes, whereas J-proteins of the DNAJC14, ZCSL3, FLJ13236, and C21orf55 groups are conserved between humans and protostomes but were not found in Ciona. J-proteins of the sacsin group seem to be specific to vertebrates. There is also a J-like protein without a conserved HPD tripeptide motif in the Ciona genome. The Ciona genome encodes 3 types of BAG family proteins, all of which have human and protostome counterparts (BAG1, BAG3, and BAT3). BAG2 group is conserved between humans and protostomes but was not found in Ciona, and BAG4 and BAG5 groups seem to be specific to vertebrates. Members for SIL1, UBQLN, UBADC1, TIMM44, GRPEL, and Magmas groups, which are conserved between humans and protostomes, were also found in Ciona. No Ciona member was retrieved for HSPBP1 group, which is conserved between humans and protostomes. For several groups of the HSP70 superfamily, J-proteins, and other types of cochaperones, multiple members in humans are represented by a single counterpart in Ciona. These results show that genes of the HSP70 chaperone system can be distinguished into groups that are shared by vertebrates, Ciona, and protostomes, ones shared by vertebrates and protostomes, ones shared by vertebrates and Ciona, and ones specific to vertebrates, Ciona, or protostomes. These results also demonstrate that the components of the HSP70 chaperone system in Ciona are similar to but simpler than those in humans and suggest that changes of the genome in the lineage leading to humans after the separation from that leading to Ciona increased the number and diversity of members of the HSP70 chaperone system. Changes of the genome in the lineage leading to Ciona also seem to have made the HSP70 chaperone system in this species slightly simpler than that in the common ancestor of humans and Ciona.
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Affiliation(s)
- Shuichi Wada
- CREST, Japan Science Technology Agency, Kawaguchi, Saitama 333-0012 [corrected] Japan.
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24
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Aouacheria A, Brunet F, Gouy M. Phylogenomics of Life-Or-Death Switches in Multicellular Animals: Bcl-2, BH3-Only, and BNip Families of Apoptotic Regulators. Mol Biol Evol 2005; 22:2395-416. [PMID: 16093567 DOI: 10.1093/molbev/msi234] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
In this report, we conducted a comprehensive survey of Bcl-2 family members, a divergent group of proteins that regulate programmed cell death by an evolutionarily conserved mechanism. Using comparative sequence analysis, we found novel sequences in mammals, nonmammalian vertebrates, and in a number of invertebrates. We then asked what conclusions could be drawn from phyletic distribution, intron/exon structures, sequence/structure relationships, and phylogenetic analyses within the updated Bcl-2 family. First, multidomain members having a sequence pattern consistent with the conservation of the Bcl-X(L)/Bax/Bid topology appear to be restricted to multicellular animals and may share a common ancestry. Next, BNip proteins, which were originally identified based on their ability to bind to E1B 19K/Bcl-2 proteins, form three independent monophyletic branches with different evolutionary history. Lastly, a set of Bcl-2 homology 3-only proteins with unrelated secondary structures seems to have evolved after the origin of Metazoa and exhibits diverse expansion after speciation during vertebrate evolution.
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Affiliation(s)
- Abdel Aouacheria
- Laboratoire de Biométrie et Biologie Evolutive, Université Claude Bernard Lyon 1, 69622 Villeurbanne Cedex, France.
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25
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Meinertzhagen IA, Lemaire P, Okamura Y. The neurobiology of the ascidian tadpole larva: recent developments in an ancient chordate. Annu Rev Neurosci 2004; 27:453-85. [PMID: 15217340 DOI: 10.1146/annurev.neuro.27.070203.144255] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
With little more than 330 cells, two thirds within the sensory vesicle, the CNS of the tadpole larva of the ascidian Ciona intestinalis provides us with a chordate nervous system in miniature. Neurulation, neurogenesis and its genetic bases, as well as the gene expression territories of this tiny constituency of cells all follow a chordate plan, giving rise in some cases to frank structural homologies with the vertebrate brain. Recent advances are fueled by the release of the genome and EST expression databases and by the development of methods to transfect embryos by electroporation. Immediate prospects to test the function of neural genes are based on the isolation of mutants by classical genetics and insertional mutagenesis, as well as by the disruption of gene function by morpholino antisense oligo-nucleotides. Coupled with high-speed video analysis of larval swimming, optophysiological methods offer the prospect to analyze at single-cell level the function of a CNS built on a vertebrate plan.
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26
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Cole AG, Meinertzhagen IA. The central nervous system of the ascidian larva: mitotic history of cells forming the neural tube in late embryonic Ciona intestinalis. Dev Biol 2004; 271:239-62. [PMID: 15223332 DOI: 10.1016/j.ydbio.2004.04.001] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2003] [Revised: 04/01/2004] [Accepted: 04/01/2004] [Indexed: 11/23/2022]
Abstract
Ascidian larvae develop after an invariant pattern of embryonic cleavage. Fewer than 400 cells constitute the larval central nervous system (CNS), which forms without either extensive migration or cell death. We catalogue the mitotic history of these cells in Ciona intestinalis, using confocal microscopy of whole-mount embryos at stages from neurulation until hatching. The positions of cells contributing to the CNS were reconstructed from confocal image stacks of embryonic nuclei, and maps of successive stages were used to chart the mitotic descent, thereby creating a cell lineage for each cell. The entire CNS is formed from 10th- to 14th-generation cells. Although minor differences exist in cell position, lineage is invariant in cells derived from A-line blastomeres, which form the caudal nerve cord and visceral ganglion. We document the lineage of five pairs of presumed motor neurons within the visceral ganglion: one pair arises from A/A 10.57, and four from progeny of A/A 9.30. The remaining cells of the visceral ganglion are in their 13th and 14th generations at hatching, with most mitotic activity ceasing around 85% of embryonic development. Of the approximately 330 larval cells previously reported in the CNS of Ciona, we document the lineage of 226 that derive predominantly from A-line blastomeres.
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Affiliation(s)
- Alison G Cole
- Biology Department, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J1
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27
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Shoguchi E, Ikuta T, Yoshizaki F, Satou Y, Satoh N, Asano K, Saiga H, Nishikata T. Fluorescent in situ hybridization to ascidian chromosomes. Zoolog Sci 2004; 21:153-7. [PMID: 14993826 DOI: 10.2108/zsj.21.153] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The draft genome of the ascidian Ciona intestinalis has been sequenced. Mapping of the genome sequence to the Ciona 14 haploid chromosomes is essential for future studies of the genome-wide control of gene expression in this basal chordate. Here we describe an efficient protocol for fluorescent in situ hybridization for mapping genes to the Ciona chromosomes. We demonstrate how the locations of two BAC clones can be mapped relative to each other. We also show that this method is efficient for coupling two so-far independent scaffolds into one longer scaffold when two BAC clones represent sequences located at either end of the two scaffolds.
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Affiliation(s)
- Eiichi Shoguchi
- Department of Zoology, Graduate School of Science, Kyoto University, Japan.
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