1
|
De Vos S, Rombauts S, Coussement L, Dermauw W, Vuylsteke M, Sorgeloos P, Clegg JS, Nambu Z, Van Nieuwerburgh F, Norouzitallab P, Van Leeuwen T, De Meyer T, Van Stappen G, Van de Peer Y, Bossier P. The genome of the extremophile Artemia provides insight into strategies to cope with extreme environments. BMC Genomics 2021; 22:635. [PMID: 34465293 PMCID: PMC8406910 DOI: 10.1186/s12864-021-07937-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 08/14/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Brine shrimp Artemia have an unequalled ability to endure extreme salinity and complete anoxia. This study aims to elucidate its strategies to cope with these stressors. RESULTS AND DISCUSSION Here, we present the genome of an inbred A. franciscana Kellogg, 1906. We identified 21,828 genes of which, under high salinity, 674 genes and under anoxia, 900 genes were differentially expressed (42%, respectively 30% were annotated). Under high salinity, relevant stress genes and pathways included several Heat Shock Protein and Leaf Embryogenesis Abundant genes, as well as the trehalose metabolism. In addition, based on differential gene expression analysis, it can be hypothesized that a high oxidative stress response and endocytosis/exocytosis are potential salt management strategies, in addition to the expression of major facilitator superfamily genes responsible for transmembrane ion transport. Under anoxia, genes involved in mitochondrial function, mTOR signalling and autophagy were differentially expressed. Both high salt and anoxia enhanced degradation of erroneous proteins and protein chaperoning. Compared with other branchiopod genomes, Artemia had 0.03% contracted and 6% expanded orthogroups, in which 14% of the genes were differentially expressed under high salinity or anoxia. One phospholipase D gene family, shown to be important in plant stress response, was uniquely present in both extremophiles Artemia and the tardigrade Hypsibius dujardini, yet not differentially expressed under the described experimental conditions. CONCLUSIONS A relatively complete genome of Artemia was assembled, annotated and analysed, facilitating research on its extremophile features, and providing a reference sequence for crustacean research.
Collapse
Affiliation(s)
- Stephanie De Vos
- Laboratory of Aquaculture & Artemia Reference Center, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
- Department of Plant Systems Biology, VIB, Department of Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
| | - Stephane Rombauts
- Department of Plant Systems Biology, VIB, Department of Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
| | - Louis Coussement
- Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Wannes Dermauw
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | | | - Patrick Sorgeloos
- Laboratory of Aquaculture & Artemia Reference Center, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - James S Clegg
- Coastal and Marine Sciences Institute, University of California, Bodega Bay, Davis, CA, USA
| | - Ziro Nambu
- Department of Medical Technology, School of Health Sciences, University of Occupational and Environmental Health, Japan, Kitakyushu, Fukuoka, Japan
| | - Filip Van Nieuwerburgh
- Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Parisa Norouzitallab
- Laboratory of Aquaculture & Artemia Reference Center, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
- Laboratory for Immunology and Animal Biotechnology, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Thomas Van Leeuwen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Tim De Meyer
- Department of Data Analysis and Mathematical Modelling, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Gilbert Van Stappen
- Laboratory of Aquaculture & Artemia Reference Center, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Yves Van de Peer
- Department of Plant Systems Biology, VIB, Department of Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Centre for Microbial Ecology and Genomics, Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria, South Africa
| | - Peter Bossier
- Laboratory of Aquaculture & Artemia Reference Center, Department of Animal Sciences and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
| |
Collapse
|
2
|
Abstract
Winged insects underwent an unparalleled evolutionary radiation, but mechanisms underlying the origin and diversification of wings in basal insects are sparsely known compared with more derived holometabolous insects. In the neopteran species Oncopeltus fasciatus, we manipulated wing specification genes and used RNA-seq to obtain both functional and genomic perspectives. Combined with previous studies, our results suggest the following key steps in wing origin and diversification. First, a set of dorsally derived outgrowths evolved along a number of body segments including the first thoracic segment (T1). Homeotic genes were subsequently co-opted to suppress growth of some dorsal flaps in the thorax and abdomen. In T1 this suppression was accomplished by Sex combs reduced, that when experimentally removed, results in an ectopic T1 flap similar to prothoracic winglets present in fossil hemipteroids and other early insects. Global gene-expression differences in ectopic T1 vs. T2/T3 wings suggest that the transition from flaps to wings required ventrally originating cells, homologous with those in ancestral arthropod gill flaps/epipods, to migrate dorsally and fuse with the dorsal flap tissue thereby bringing new functional gene networks; these presumably enabled the T2/T3 wing's increased size and functionality. Third, "fused" wings became both the wing blade and surrounding regions of the dorsal thorax cuticle, providing tissue for subsequent modifications including wing folding and the fit of folded wings. Finally, Ultrabithorax was co-opted to uncouple the morphology of T2 and T3 wings and to act as a general modifier of hindwings, which in turn governed the subsequent diversification of lineage-specific wing forms.
Collapse
|
3
|
Kim BY, Song HY, Kim MY, Lee BH, Kim KJ, Jo KJ, Kim SW, Lee SG, Lee BH. DISTINCTIVE LOCALIZATION OF GROUP 3 LATE EMBRYOGENESIS ABUNDANT SYNTHESIZING CELLS DURING BRINE SHRIMP DEVELOPMENT. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2015; 89:169-180. [PMID: 25781424 DOI: 10.1002/arch.21234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Despite numerous studies on late embryogenesis abundant (LEA) proteins, their functions, roles, and localizations during developmental stages in arthropods remain unknown. LEA proteins protect crucial proteins against osmotic stress during the development and growth of various organisms. Thus, in this study, fluorescence in situ hybridization was used to determine the crucial regions protected against osmotic stress as well as the distinctive localization of group 3 (G3) LEA(+) cells during brine shrimp development. Several cell types were found to synthesize G3 LEA RNA, including neurons, muscular cells, APH-1(+) cells, and renal cells. The G3 LEA(+) neuronal cell bodies outside of the mushroom body projected their axonal bundles to the central body, but those inside the mushroom body projected their axonal bundles toward the deutocerebrum without innervating the central body. The cell bodies inside the mushroom body received axons of the G3 LEA(+) sensory cells at the medial ventral cup of the nauplius eye. Several glands were found to synthesize G3 LEA RNA during the nauplius stages of brine shrimp, including the sinus, antennal I and II, salt, and three ectodermal glands. This study provides the first demonstration of the formation of G3 LEA(+) sinus glands at the emergence stages of brine shrimp. These results suggest that G3 LEA protein is synthesized in several cell types. In particular, specific glands play crucial roles during the emergence and nauplius stages of brine shrimp.
Collapse
Affiliation(s)
- Bo Yong Kim
- School of Life Sciences and Biotechnology, Korea University, Korea
| | - Hwa Young Song
- School of Life Sciences and Biotechnology, Korea University, Korea
| | - Mi Young Kim
- School of Life Sciences and Biotechnology, Korea University, Korea
| | - Bong Hee Lee
- School of Life Sciences and Biotechnology, Korea University, Korea
| | - Kyung Joo Kim
- Department of Clinical Laboratory Sciences, College of Health Science, Korea University, Korea
| | - Kyung Jin Jo
- Department of Clinical Laboratory Sciences, College of Health Science, Korea University, Korea
| | - Suhng Wook Kim
- Department of Clinical Laboratory Sciences, College of Health Science, Korea University, Korea
| | - Seung Gwan Lee
- Department of Clinical Laboratory Sciences, College of Health Science, Korea University, Korea
| | | |
Collapse
|
4
|
Cloning and expression profiling of a cuticular protein gene in Daphnia carinata. Dev Genes Evol 2014; 224:129-35. [DOI: 10.1007/s00427-014-0469-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 02/07/2014] [Indexed: 11/30/2022]
|
5
|
Wang JQ, Hou L, Yi N, Zhang RF, Zou XY. Molecular analysis and its expression of a pou homeobox protein gene during development and in response to salinity stress from brine shrimp, Artemia sinica. Comp Biochem Physiol A Mol Integr Physiol 2011; 161:36-43. [PMID: 21911072 DOI: 10.1016/j.cbpa.2011.08.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 08/29/2011] [Accepted: 08/29/2011] [Indexed: 10/17/2022]
Abstract
Brine shrimps of the genus Artemia are aquatic species of economic importance because of their important significance to aquaculture and are used as a model species in physiology and developmental biology. Research on Artemia POU homeobox gene function will enhance our understanding of the physiological and developmental processes of POU homeobox gene in animals. Herein, a full-length cDNA encoding an Artemia POU homeobox protein gene 1 (APH-1) from Artemia sinica (designated as As-APH-1) was cloned and characterized by a reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE) method. The As-APH-1 gene encoded a protein of 388 amino acid polypeptide with a calculated molecular mass of 42.85kDa and an isoelectric point of 6.90 and the protein belongs to the POU III family. Multiple sequence alignments revealed that A. sinica As-APH-1 protein sequence shared a conserved POU homeobox domain with other species. The early and persistent expression of As-APH-1 in the naupliar stages by semi-quantitative RT-PCR and whole-mount embryonic immunohistochemistry suggest that As-APH-1 functions very early in the salt gland and may be required continuously in this organ. Later in development, expression of As-APH-1 begins to dramatically decrease and disappear in salt gland of the sub-adult Artemia. In addition, we also discovered that As-APH-1 increased obviously as the salinity increased, indicating that As-APH-1 might be used as a good indicator of salinity stress. In summary, we are the first to identify the As-APH-1 gene and to determine its gene expression patterns in early embryogenesis stages and in different salinity stress in brine shrimp, A. sinica. The result of expression of As-APH-1 affected by salinity changes will provide us further understanding of the underlying mechanisms of osmoregulation in Artemia early embryonic development.
Collapse
Affiliation(s)
- Jia-Qing Wang
- College of Science and Technology, Shenyang Agricultural University, Fushun, PR China
| | | | | | | | | |
Collapse
|
6
|
Wang JQ, Hou L, Yi N, Zhang RF, Zou XY, Xiao Q, Guo R. Molecular cloning and its expression of trachealess gene (As-trh) during development in brine shrimp, Artemia sinica. Mol Biol Rep 2011; 39:1659-65. [PMID: 21625858 DOI: 10.1007/s11033-011-0905-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 05/18/2011] [Indexed: 12/12/2022]
Abstract
Basic helix-loop-helix-PAS (bHLH-PAS) family transcription factors are implicated in multiple developmental and physiological regulatory processes. Herein, a full-length cDNA encoding a bHLH-PAS domain transcription factor trachealess gene (designated as As-trh) was cloned and characterized from brine shrimp (Artemia sinica) for the first time. The full-length cDNA of As-trh was 2,698 bp with a 2,319 bp open reading frame encoding a deduced protein of 772 amino acid polypeptide with a calculated molecular mass of 86.02 kDa and an isoelectric point of 5.87. Sequence alignment revealed that As-trh had high homology with other species trh gene, including the D-trh gene in Drosophila melanogaster and Bm-trh in Bombyx mori. The early and persistent expression of As-trh in the naupliar stages by whole-mount embryonic in situ hybridization and immunohistochemistry suggest that As-trh functions very early in the salt gland and may be required continuously in this tissue. Later in development, expression of As-trh begins to decrease and disappear in salt gland of the older nauplius and appears in the thoracic epipods of the sub-adult Artemia. These results indicated that As-trh might play an important role in osmoregulatiory organ development from the larvae stages through adult stages.
Collapse
Affiliation(s)
- Jia-Qing Wang
- College of Ocean, Agricultural University of Hebei, Qinhuangdao 066003, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
7
|
Armstrong KR, Chamberlin HM. Coordinate regulation of gene expression in the C. elegans excretory cell by the POU domain protein CEH-6. Mol Genet Genomics 2009; 283:73-87. [PMID: 19921263 DOI: 10.1007/s00438-009-0497-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Accepted: 10/23/2009] [Indexed: 11/24/2022]
Abstract
Excretory renal organs are critical in animals for osmoregulation and the elimination of waste. Renal organs across a range of species exhibit cellular and molecular similarities. For example, class III POU-homeodomain transcription factors are expressed in the renal organs of many invertebrates and vertebrates. However, the functional role for these factors is not well characterized. To better understand the role of class III POU-homeodomain proteins in animal excretory systems, we have characterized a set of genes expressed in the Caenorhabditis elegans excretory cell, and determined their regulation by the POU-III transcription factor CEH-6. Our molecular and biochemical studies show that CEH-6 regulates a subset of genes expressed in the excretory cell. Additionally, we find that the CEH-6-dependent genes share two molecular features: they contain at least one octamer regulatory element and they encode for transport and channel proteins. This work suggests that a role for POU-III factors in renal organs is to coordinate the expression of a set of functionally related genes.
Collapse
Affiliation(s)
- Kristin R Armstrong
- Department of Molecular Genetics, Ohio State University, 938 Biological Sciences Building, 484 W. 12th Avenue, Columbus, OH 43210, USA
| | | |
Collapse
|
8
|
Zhang TY, Xu WH. Identification and characterization of a POU transcription factor in the cotton bollworm, Helicoverpa armigera. BMC Mol Biol 2009; 10:25. [PMID: 19320969 PMCID: PMC2672083 DOI: 10.1186/1471-2199-10-25] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Accepted: 03/25/2009] [Indexed: 11/10/2022] Open
Abstract
Background The POU family genes containing the POU domain are common in vertebrates and invertebrates and play critical roles in cell-type-specific gene expression and cell fate determination. Results Har-POU, a new member of the POU gene family, was cloned from the suboesophageal ganglion of Helicoverpa armigera (Har), and its potential functions in the development of the central nervous system (CNS) were analyzed. Southern blot analysis suggests that a single copy of this gene is present in the H. armigera haploid genome. Har-POU mRNA is distributed widely in various tissues and expressed highly in the CNS, salivary gland, and trachea. In vitro-translated Har-POU specifically bound canonical octamer motifs on the promoter of diapause hormone and pheromone biosynthesis activating neuropeptide (DH-PBAN) gene in H. armigera. Expression of the Har-POU gene is markedly higher in the CNS of nondiapause-destined pupae than in diapause-destined pupae. Expression of the Har-POU gene in diapausing pupae was upregulated quickly by injection of ecdysone. Conclusion Har-POU may respond to ecdysone and bind to the promoter of DH-PBAN gene to regulate pupal development in H. armigera.
Collapse
Affiliation(s)
- Tian-Yi Zhang
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou 510275, PR China.
| | | |
Collapse
|
9
|
Conte FP. Molecular domains in epithelial salt cellNaCl of crustacean salt gland (Artemia). INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 268:39-57. [PMID: 18703403 DOI: 10.1016/s1937-6448(08)00802-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
The salt secretory cell has two distinct patterns of plasma membrane development. First, the basolateral surface forms a tubular labyrinth. It contains the subunit alpha-2 of the Na(+)-K(+)-ATPase bound together with a beta subunit for structural attachment within the lipid bilayer. Second, the apical plasma membranes form a multiple array of extending tufts. These tufts contain the subunit alpha-1 of the Na(+)-K(+)-ATPase bound together with a beta subunit for structural integrity within the lipid bilayer. The presence of an active transporter for chloride remains as an open question. It has been taken as preliminary evidence from brine shrimp cystic fibrosis toxicity that a cystic fibrosis transmembrane conductance regulator chloride channel could be present in the apical region. The presence of cytoskeletal elements being involved in the construction of a hypo-osmoregulatory apparatus is supported by the homeobox gene products derived from APH-1 m RNA found in the salt gland.
Collapse
Affiliation(s)
- Frank P Conte
- Department of Zoology, Oregon State University, Corvallis, Oregon 97331, USA
| |
Collapse
|
10
|
Mah AK, Armstrong KR, Chew DS, Chu JS, Tu DK, Johnsen RC, Chen N, Chamberlin HM, Baillie DL. Transcriptional regulation of AQP-8, a Caenorhabditis elegans aquaporin exclusively expressed in the excretory system, by the POU homeobox transcription factor CEH-6. J Biol Chem 2007; 282:28074-86. [PMID: 17660295 DOI: 10.1074/jbc.m703305200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Due to the ever changing environmental conditions in soil, regulation of osmotic homeostasis in the soil-dwelling nematode Caenorhabditis elegans is critical. AQP-8 is a C. elegans aquaporin that is expressed in the excretory cell, a renal equivalent tissue, where the protein participates in maintaining water balance. To better understand the regulation of AQP-8, we undertook a promoter analysis to identify the aqp-8 cis-regulatory elements. Using progressive 5' deletions of upstream sequence, we have mapped an essential regulatory region to roughly 300 bp upstream of the translational start site of aqp-8. Analysis of this region revealed a sequence corresponding to a known DNA functional element (octamer motif), which interacts with POU homeobox transcription factors. Phylogenetic footprinting showed that this site is perfectly conserved in four nematode species. The octamer site's function was further confirmed by deletion analyses, mutagenesis, functional studies, and electrophoretic mobility shift assays. Of the three POU homeobox proteins encoded in the C. elegans genome, CEH-6 is the only member that is expressed in the excretory cell. We show that expression of AQP-8 is regulated by CEH-6 by performing RNA interference experiments. CEH-6's mammalian ortholog, Brn1, is expressed both in the kidney and the central nervous system and binds to the same octamer consensus binding site to drive gene expression. These parallels in transcriptional control between Brn1 and CEH-6 suggest that C. elegans may well be an appropriate model for determining gene-regulatory networks in the developing vertebrate kidney.
Collapse
Affiliation(s)
- Allan K Mah
- Department Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Franch-Marro X, Martín N, Averof M, Casanova J. Association of tracheal placodes with leg primordia inDrosophilaand implications for the origin of insect tracheal systems. Development 2006; 133:785-90. [PMID: 16469971 DOI: 10.1242/dev.02260] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Adaptation to diverse habitats has prompted the development of distinct organs in different animals to better exploit their living conditions. This is the case for the respiratory organs of arthropods, ranging from tracheae in terrestrial insects to gills in aquatic crustaceans. Although Drosophila tracheal development has been studied extensively, the origin of the tracheal system has been a long-standing mystery. Here, we show that tracheal placodes and leg primordia arise from a common pool of cells in Drosophila, with differences in their fate controlled by the activation state of the wingless signalling pathway. We have also been able to elucidate early events that trigger leg specification and to show that cryptic appendage primordia are associated with the tracheal placodes even in abdominal segments. The association between tracheal and appendage primordia in Drosophila is reminiscent of the association between gills and appendages in crustaceans. This similarity is strengthened by the finding that homologues of tracheal inducer genes are specifically expressed in the gills of crustaceans. We conclude that crustacean gills and insect tracheae share a number of features that raise the possibility of an evolutionary relationship between these structures. We propose an evolutionary scenario that accommodates the available data.
Collapse
Affiliation(s)
- Xavier Franch-Marro
- Institut de Biologia Molecular de Barcelona, CSIC, Barcelona, C/Josep Samitier 1-5, 08028 Barcelona, Spain
| | | | | | | |
Collapse
|
12
|
Abstract
The Drosophila trachealess gene encodes a basic-helix-loop-helix-PAS transcription factor that controls the formation of the trachea and salivary duct. An ortholog of trachealess was identified in the brine shrimp, Artemia franciscana, and was shown to be highly conserved by sequence identity. Expression of Artemia trachealess was observed at two sites during development: the naupliar salt gland and the juvenile thoracic epipod. These two organs function at their respective times of development in osmoregulation, an important aspect of brine shrimp physiology. This extends the range of putative functions of trachealess to include formation of osmoregulatory, respiratory, and ductile organs.
Collapse
Affiliation(s)
- Brian Mitchell
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill, 27599-3280, USA
| | | |
Collapse
|
13
|
Candiani S, Castagnola P, Oliveri D, Pestarino M. Cloning and developmental expression of AmphiBrn1/2/4, a POU III gene in amphioxus. Mech Dev 2002; 116:231-4. [PMID: 12128231 DOI: 10.1016/s0925-4773(02)00146-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The large family encoding POU transcription factors has been described in several species. In particular, class III POU genes regulate critical steps of vertebrate and invertebrate neurogenesis. A novel amphioxus class III POU gene, AmphiBrn1/2/4, has been isolated and its spatio-temporal expression has been reported. AmphiBrn1/2/4 is first expressed in the dorsal epiblast, then throughout the neural plate except for a gap at level of the anterior region of the cerebral vesicle. Transcripts are also detected in the primordium of gill slits, pharynx and left Hatschek's diverticulum.
Collapse
Affiliation(s)
- Simona Candiani
- Dipartimento di Biologia Sperimentale, Ambientale e Applicata, Università di Genova, viale Benedetto XV 5, Italy
| | | | | | | |
Collapse
|
14
|
O'Brien EK, Degnan BM. Pleiotropic developmental expression of HasPOU-III, a class III POU gene, in the gastropod Haliotis asinina. Mech Dev 2002; 114:129-32. [PMID: 12175498 DOI: 10.1016/s0925-4773(02)00037-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
HasPOU-III is expressed in multiple cell types during the first 3 days of development of the gastropod Haliotis asinina. HasPOU-III expression begins in two bilaterally symmetrical sets of cells on the ventral ectodermal surface of the trochophore larva; one set are putative foot mucous cells. After torsion, HasPOU-III transcripts transiently appear in the developing ganglia of the central nervous system. At the end of larval morphogenesis, HasPOU-III expression is initiated in dorsoposterior cells of the visceral mass, in the posterior cells of the statocyst and in the developing radular sac. These expression patterns in Haliotis, a spiralian lophotrochozoan, are similar to POU Class III genes in other bilaterians where expression occurs in secretory cells and the developing nervous system.
Collapse
Affiliation(s)
- Elizabeth K O'Brien
- Department of Zoology and Entomology, University of Queensland, Brisbane, Queensland 4072, Australia
| | | |
Collapse
|
15
|
Bürglin TR, Ruvkun G. Regulation of ectodermal and excretory function by the C. elegans POU homeobox gene ceh-6. Development 2001; 128:779-90. [PMID: 11171402 DOI: 10.1242/dev.128.5.779] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Caenorhabditis elegans has three POU homeobox genes, unc-86, ceh-6 and ceh-18. ceh-6 is the ortholog of vertebrate Brn1, Brn2, SCIP/Oct6 and Brn4 and fly Cf1a/drifter/ventral veinless. Comparison of C. elegans and C. briggsae CEH-6 shows that it is highly conserved. C. elegans has only three POU homeobox genes, while Drosophila has five that fall into four families. Immunofluorescent detection of the CEH-6 protein reveals that it is expressed in particular head and ventral cord neurons, as well as in rectal epithelial cells, and in the excretory cell, which is required for osmoregulation. A deletion of the ceh-6 locus causes 80% embryonic lethality. During morphogenesis, embryos extrude cells in the rectal region of the tail or rupture, indicative of a defect in the rectal epithelial cells that express ceh-6. Those embryos that hatch are sick and develop vacuoles, a phenotype similar to that caused by laser ablation of the excretory cell. A GFP reporter construct expressed in the excretory cell reveals inappropriate canal structures in the ceh-6 null mutant. Members of the POU-III family are expressed in tissues involved in osmoregulation and secretion in a number of species. We propose that one evolutionary conserved function of the POU-III transcription factor class could be the regulation of genes that mediate secretion/osmoregulation.
Collapse
Affiliation(s)
- T R Bürglin
- Department of Molecular Biology, Massachusetts General Hospital, Fruit Street, Boston, MA 02114, USA.
| | | |
Collapse
|