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Zhi F, Jiang DN, Mustapha UF, Li SX, Shi HJ, Li GL, Zhu CH. Expression and regulation of 42Sp50 in spotted scat (Scatophagus argus). Front Genet 2022; 13:964150. [PMID: 36035129 PMCID: PMC9403048 DOI: 10.3389/fgene.2022.964150] [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] [Received: 06/08/2022] [Accepted: 07/14/2022] [Indexed: 11/13/2022] Open
Abstract
42Sp50 is an isoform of the eukaryotic translation elongation factor 1 A (eEF1A) and is vital for fish ovarian development. Spotted scat (Scatophagus argus) is a popular marine cultured fish species in Southern Asia and China, and its artificial reproduction is complicated, with a relatively low success ratio in practice. In this study, the 42Sp50 gene was cloned from spotted scat. Tissue distribution analysis showed that 42Sp50 was mainly expressed in the ovary. qRT-PCR showed that 42Sp50 expression levels gradually decreased insignificantly in the ovaries from phase II to IV. Western blot analysis showed that 42Sp50 was highly expressed in the ovary, while it was almost undetectable in the testis. Immunohistochemistry analysis stained 42Sp50 mainly in the cytoplasm of the previtellogenic oocytes in ovaries of normal XX-female and sex-reversed XY-female. Aside from fish and amphibians, 42Sp50 was also identified in some reptile species using genomic database searching. Analyses of the transcriptome data from four different fish species (Hainan medaka (Oryzias curvinotus), silver sillago (Sillago sihama), Nile tilapia (Oreochromis niloticus), and Hong Kong catfish (Clarias fuscus)) revealed ovaries biased expression of 42Sp50 in all, similar to spotted scat. While the neighbor genes of 42Sp50 did not show ovary biased expression in the fish species analyzed. Bisulfite Sequencing PCR (BSP) results showed that the DNA methylation level of 42Sp50 promoter was low in ovaries, testes, and muscles. The luciferase reporter assay demonstrated that Dmrt4 activated 42Sp50 expression in the presence of Sf1 or Foxh1. These results suggest that 42Sp50 may be involved in regulating the early phase oocytes development of spotted scat.
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Mustapha UF, Zhi F, Huang YQ, Assan D, Li GL, Jiang DN. First account of a transient intersex in spotted scat, Scatophagus argus: a marine gonochoristic fish. FISH PHYSIOLOGY AND BIOCHEMISTRY 2022; 48:1011-1023. [PMID: 35804212 DOI: 10.1007/s10695-022-01097-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
This study presents the first incidence of intersex associated with testis-ova in spotted scat (Scatophagus argus) reared in a controlled environment. The testis-ova is associated with the abnormal occurrence of primary oocytes (POs) in some male testis and is referred to as ectopic primary oocytes (Ecto-PO), whiles individuals with Ecto-PO are called "Ecto-PO gonad/individuals." We investigated gonads of 129 male spotted scat aged 4-12 and 18 months after hatch (mah) by histological studies for the presence of female sexual characteristics. A total of 20 out of 88 gonads representing 22.7% of male fish aged 6-12, or 15.5% of all male fish sampled, were found to have visible Ecto-PO. At least, the Ecto-PO had an average of 7 oocytes per gonadal section, indicating high severity. The Ecto-PO appears after sex differentiation and degenerates during sexual maturation. The Ecto-PO did not significantly influence the expression pattern of male and female sex-related genes performed using qPCR. Immunofluorescence of 42sp50 specifically stained the Ecto-PO without influence from the surrounding testicular tissues. In addition, temperature did not correlate with the proliferation of the Ecto-PO, but rather gonad developmental strategy. The results show that the naturally occurring Ecto-PO might not be detrimental to testis development and could be considered a frequent-high-level incidence of natural aberration. This study highlights the intricacy of fish sex differentiation and provides a new research chapter to ascertain the mystery behind the occurrence of Ecto-PO.
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Affiliation(s)
- Umar Farouk Mustapha
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy culture, Guangdong Province Famous Fish Reproduction and Breeding Engineering Technology Research Center, Zhanjiang, 524088, China
| | - Fei Zhi
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy culture, Guangdong Province Famous Fish Reproduction and Breeding Engineering Technology Research Center, Zhanjiang, 524088, China
| | - Yuang-Qing Huang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy culture, Guangdong Province Famous Fish Reproduction and Breeding Engineering Technology Research Center, Zhanjiang, 524088, China
| | - Daniel Assan
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy culture, Guangdong Province Famous Fish Reproduction and Breeding Engineering Technology Research Center, Zhanjiang, 524088, China
| | - Guang-Li Li
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy culture, Guangdong Province Famous Fish Reproduction and Breeding Engineering Technology Research Center, Zhanjiang, 524088, China
| | - Dong-Neng Jiang
- Fisheries College of Guangdong Ocean University, Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy culture, Guangdong Province Famous Fish Reproduction and Breeding Engineering Technology Research Center, Zhanjiang, 524088, China.
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Molecular characterization of 5S ribosomal RNA genes and transcripts in the protozoan parasite Leishmania major. Parasitology 2016; 143:1917-1929. [PMID: 27707420 DOI: 10.1017/s0031182016001712] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Eukaryotic 5S rRNA, synthesized by RNA polymerase III (Pol III), is an essential component of the large ribosomal subunit. Most organisms contain hundreds of 5S rRNA genes organized into tandem arrays. However, the genome of the protozoan parasite Leishmania major contains only 11 copies of the 5S rRNA gene, which are interspersed and associated with other Pol III-transcribed genes. Here we report that, in general, the number and order of the 5S rRNA genes is conserved between different species of Leishmania. While in most organisms 5S rRNA genes are normally associated with the nucleolus, combined fluorescent in situ hybridization and indirect immunofluorescence experiments showed that 5S rRNA genes are mainly located at the nuclear periphery in L. major. Similarly, the tandemly repeated 5S rRNA genes in Trypanosoma cruzi are dispersed throughout the nucleus. In contrast, 5S rRNA transcripts in L. major were localized within the nucleolus, and scattered throughout the cytoplasm, where mature ribosomes are located. Unlike other rRNA species, stable antisense RNA complementary to 5S rRNA is not detected in L. major.
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Visualizing protein interactions involved in the formation of the 42S RNP storage particle of Xenopus oocytes. Biol Cell 2012; 102:469-78. [DOI: 10.1042/bc20100034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Kinoshita M, Okamoto G, Hirata T, Shinomiya A, Kobayashi T, Kubo Y, Hori H, Kanamori A. Transgenic medaka enables easy oocytes detection in live fish. Mol Reprod Dev 2009; 76:202-7. [PMID: 18543284 DOI: 10.1002/mrd.20942] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Easy oocyte detection in living specimens benefits various developmental biology and environmental toxicology studies. One of the earliest markers of sex differentiation in medaka (Oryzias latipes) is oocyte development. Within the field of toxicology, a simple detection method for induced oocyte in the testis (testis-ova) as a result of endocrine disruption is necessary. In this study we produced transgenic medaka whose oocytes were labeled with fluorescent proteins using the regulatory region of the 42Sp50 gene, an isoform of polypeptide elongation 1-alpha. Short (201 nt) 5'- and 3'-flanking regions were sufficient for reporter gene expression. GFP expression was first observed in female germ cells approximately 5 days post-hatching. In the mature ovaries, germ cells showed such intense fluorescence that the fluorescence was observed from outside the body wall. In contrast, very faint fluorescence was observed in the mature testes. Testis-ova, oocytes artificially induced in the testes, were also labeled with GFP. These findings indicate through the use of transgenic medaka, that detection of female germ cells was straightforward and this transgenic medaka model proves useful for tracking female germ cells in developmental and toxicological studies.
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Affiliation(s)
- Masato Kinoshita
- Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
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Zhang J, Harnpicharnchai P, Jakovljevic J, Tang L, Guo Y, Oeffinger M, Rout MP, Hiley SL, Hughes T, Woolford JL. Assembly factors Rpf2 and Rrs1 recruit 5S rRNA and ribosomal proteins rpL5 and rpL11 into nascent ribosomes. Genes Dev 2007; 21:2580-92. [PMID: 17938242 PMCID: PMC2000323 DOI: 10.1101/gad.1569307] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Accepted: 08/21/2007] [Indexed: 12/31/2022]
Abstract
More than 170 proteins are necessary for assembly of ribosomes in eukaryotes. However, cofactors that function with each of these proteins, substrates on which they act, and the precise functions of assembly factors--e.g., recruiting other molecules into preribosomes or triggering structural rearrangements of pre-rRNPs--remain mostly unknown. Here we investigated the recruitment of two ribosomal proteins and 5S ribosomal RNA (rRNA) into nascent ribosomes. We identified a ribonucleoprotein neighborhood in preribosomes that contains two yeast ribosome assembly factors, Rpf2 and Rrs1, two ribosomal proteins, rpL5 and rpL11, and 5S rRNA. Interactions between each of these four proteins have been confirmed by binding assays in vitro. These molecules assemble into 90S preribosomal particles containing 35S rRNA precursor (pre-rRNA). Rpf2 and Rrs1 are required for recruiting rpL5, rpL11, and 5S rRNA into preribosomes. In the absence of association of these molecules with pre-rRNPs, processing of 27SB pre-rRNA is blocked. Consequently, the abortive 66S pre-rRNPs are prematurely released from the nucleolus to the nucleoplasm, and cannot be exported to the cytoplasm.
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MESH Headings
- Active Transport, Cell Nucleus
- GTP Phosphohydrolases
- Genes, Fungal
- Macromolecular Substances
- Models, Biological
- Models, Molecular
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- RNA Processing, Post-Transcriptional
- RNA, Fungal/chemistry
- RNA, Fungal/genetics
- RNA, Fungal/metabolism
- RNA, Ribosomal, 5S/chemistry
- RNA, Ribosomal, 5S/genetics
- RNA, Ribosomal, 5S/metabolism
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Ribosomal Protein L10
- Ribosomal Proteins/chemistry
- Ribosomal Proteins/genetics
- Ribosomal Proteins/metabolism
- Ribosomes/genetics
- Ribosomes/metabolism
- Saccharomyces cerevisiae/genetics
- Saccharomyces cerevisiae/metabolism
- Saccharomyces cerevisiae Proteins/genetics
- Saccharomyces cerevisiae Proteins/metabolism
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Affiliation(s)
- Jingyu Zhang
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Piyanun Harnpicharnchai
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Jelena Jakovljevic
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Lan Tang
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | - Yurong Guo
- Division of Pulmonary and Critical Care Medicine, School of Medicine, John Hopkins University, Baltimore, Maryland 21224, USA
| | | | | | - Shawna L. Hiley
- Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Timothy Hughes
- Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - John L. Woolford
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
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7
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Baldauf SL. A Search for the Origins of Animals and Fungi: Comparing and Combining Molecular Data. Am Nat 1999; 154:S178-S188. [PMID: 10527926 DOI: 10.1086/303292] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Green plants, animals, and fungi have long held our interest as complex, largely multicellular eukaryotes of indeterminate origin. Considerable progress has now been made toward understanding the evolutionary relationships among these taxa as well as identifying their closest protistan relatives. An exclusive animal-fungal clade (the Opisthokonta) is now widely accepted based on an insertion in the protein synthesis elongation factor 1alpha (EF-1alpha) and molecular phylogenies of ribosomal RNAs and the conservative proteins actin, alpha-tubulin, beta-tubulin, and EF-1alpha. Protein data also suggest that the cellular (dictyostelid) and acellular (myxogastrid) slime molds are a close outgroup to the animal-fungal clade. Subsequent sequencing and phylogenetic analysis of EF-1alpha sequences very strongly support a monophyletic slime mold clade (the Mycetozoa or Eumycetozoa), which also includes the lesser-known protostelid slime molds. Monophyly of the opisthokont and mycetozoan clades, exclusive of green plants, is suggested by individual analyses of EF-1alpha and actin and given strong support by concatenated protein data. Neither the monophyly of the slime molds nor their close relationship to animals and fungi are consistently supported by ribosomal RNA data. Thus, it appears unlikely that any single molecule will accurately reconstruct all higher-order taxonomy.
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Bellé R, Minella O, Cormier P, Morales J, Poulhe R, Mulner-Lorillon O. Phosphorylation of elongation factor-1 (EF-1) by cdc2 kinase. PROGRESS IN CELL CYCLE RESEARCH 1998; 1:265-70. [PMID: 9552369 DOI: 10.1007/978-1-4615-1809-9_21] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Elongation factor-1 (EF-1) is a major substrate for cdc2 kinase in Xenopus oocytes. The guanine-nucleotide exchange factor EF-1 beta gamma delta, appears to have a highly complex macromolecular structure containing several GTP/GDP exchange proteins, valyl-tRNA synthetase, and a putative anchoring protein EF-1 gamma. During meiotic cell division, the factor becomes phosphorylated by cdc2 kinase, not only on EF-1 gamma, but also on two different phospho-acceptors on EF-1 delta. Phosphorylation is concomitant with changes in protein synthesis in vivo. Xenopus oocytes, and potentially all cells, contain a multitude of heteromeric forms of the complex which postulates that EF-1 beta gamma delta is not a "house keeping" factor but a sophisticated regulatory element.
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Affiliation(s)
- R Bellé
- Biologie Cellulaire de l'Ovocyte, CNRS URA 1449, INRA, Université Pierre et Marie Curie, Paris, France
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Kristensen P, Lund A, Clark BF, Cavallius J, Merrick WC. Purification and characterisation of a tissue specific elongation factor 1 alpha (EF-1 alpha 2) from rabbit muscle. Biochem Biophys Res Commun 1998; 245:810-4. [PMID: 9588196 DOI: 10.1006/bbrc.1998.8510] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The peptide elongation factor 1 alpha (EF-1 alpha) has been isolated and characterised from a number of species. Recently we and others have reported the existence of an isoform of the ubiquitously expressed EF-1 alpha mRNA in higher eukaryotes, including human cells. This isoform has a tissue specific expression pattern, confining it primarily to muscle, heart, and brain. In the present study we have purified the isoform of EF-1 alpha from rabbit muscle. Using partial amino acid analysis, we can conclude that in rabbit muscle essentially only the isoform of elongation factor 1 alpha, designated EF-1 alpha 2, is translated. Preliminary activity assays show that the isoform has the same functional activities as the normal EF-1 alpha, designated EF-1 alpha 1, in relation to protein synthesis, but may behave differently in the ability to bind nucleotides. Based on the availability of the isoforms of EF-1 alpha purified from a mammalian species, it will be possible to conduct further comparative studies in order to elucidate the different functions of EF-1 alpha 1 and EF-1 alpha 2 proteins.
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Affiliation(s)
- P Kristensen
- Department of Chemistry, University of Aarhus, Denmark.
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10
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Baldauf SL, Doolittle WF. Origin and evolution of the slime molds (Mycetozoa). Proc Natl Acad Sci U S A 1997; 94:12007-12. [PMID: 9342353 PMCID: PMC23686 DOI: 10.1073/pnas.94.22.12007] [Citation(s) in RCA: 236] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The Mycetozoa include the cellular (dictyostelid), acellular (myxogastrid), and protostelid slime molds. However, available molecular data are in disagreement on both the monophyly and phylogenetic position of the group. Ribosomal RNA trees show the myxogastrid and dictyostelid slime molds as unrelated early branching lineages, but actin and beta-tubulin trees place them together as a single coherent (monophyletic) group, closely related to the animal-fungal clade. We have sequenced the elongation factor-1alpha genes from one member of each division of the Mycetozoa, including Dictyostelium discoideum, for which cDNA sequences were previously available. Phylogenetic analyses of these sequences strongly support a monophyletic Mycetozoa, with the myxogastrid and dictyostelid slime molds most closely related to each other. All phylogenetic methods used also place this coherent Mycetozoan assemblage as emerging among the multicellular eukaryotes, tentatively supported as more closely related to animals + fungi than are green plants. With our data there are now three proteins that consistently support a monophyletic Mycetozoa and at least four that place these taxa within the "crown" of the eukaryote tree. We suggest that ribosomal RNA data should be more closely examined with regard to these questions, and we emphasize the importance of developing multiple sequence data sets.
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Affiliation(s)
- S L Baldauf
- Canadian Institute for Advanced Research and Department of Biochemistry, Dalhousie University, Halifax, NS, Canada B3H 4H7.
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11
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Liu QY, Baldauf SL, Reith ME. Elongation factor 1 alpha genes of the red alga Porphyra purpurea include a novel, developmentally specialized variant. PLANT MOLECULAR BIOLOGY 1996; 31:77-85. [PMID: 8704161 DOI: 10.1007/bf00020608] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The life cycle of the red alga Porphyra purpurea alternates between two morphologically distinct phases: a shell-boring, filamentous sporophyte and a free-living, foliose gametophyte. From a subtracted cDNA library enriched for sporophyte-specific sequences, we isolated a cDNA encoding an unusual elongation factor 1 alpha (EF-1 alpha) that is expressed only in the sporophyte. A second EF-1 alpha gene that is expressed equally in the sporophyte and the gametophyte was isolated from a genomic library. These are the only EF-1 alpha genes detectable in P. purpurea. The constitutively expressed gene encodes an EF-1 alpha very similar to those of most eukaryotes. However, the sporophyte-specific EF-1 alpha is one of the most divergent yet described, with nine insertions or deletions ranging in size from 1 to 26 amino acids. This is the first report of a developmental stage-specific EF-1 alpha outside of the animal kingdom and suggests a fundamental role for EF-1 alpha in the developmental process.
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Affiliation(s)
- Q Y Liu
- Institute for Marine Biosciences, National Research Council of Canada, Halifax, NS, Canada
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12
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Johnson AD, Krieg PA. A Xenopus laevis gene encoding EF-1 alpha S, the somatic form of elongation factor 1 alpha: sequence, structure, and identification of regulatory elements required for embryonic transcription. DEVELOPMENTAL GENETICS 1995; 17:280-90. [PMID: 8565334 DOI: 10.1002/dvg.1020170313] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Transcription of the Xenopus laevis EF-1 alpha S gene commences at the mid-blastula stage of embryonic development and then continues constitutively in all somatic tissues. The EF-1 alpha S promoter is extremely active in the early Xenopus embryo where EF-1 alpha S transcripts account for as much as 40% of all new polyadenylated transcripts. We have isolated the Xenopus EF-1 alpha S gene and used microinjection techniques to identify promoter elements responsible for embryonic transcription. These in vivo expression studies have identified an enhancer fragment, located approximately 4.4 kb upstream of the transcription start site, that is required for maximum expression from the EF-1 alpha S promoter. The enhancer fragment contains both an octamer and a G/C box sequence, but mutation studies indicate that the octamer plays no significant role in regulation of EF-1 alpha S expression in the embryo. The presence of a G/C element in the enhancer and of multiple G/C boxes in the proximal promoter region suggests that the G/C box binding protein, Sp1, plays a major role in the developmental regulation of EF-1 alpha S promoter activity.
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Affiliation(s)
- A D Johnson
- Department of Zoology, University of Texas at Austin 78712, USA
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13
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Kraal B, Bosch L, Mesters JR, de Graaf JM, Woudt LP, Vijgenboom E, Heinstra PW, Zeef LA, Boon C. Elongation factors in protein synthesis. CIBA FOUNDATION SYMPOSIUM 1993; 176:28-52. [PMID: 8299424 DOI: 10.1002/9780470514450.ch3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Recent discoveries of elongation factor-related proteins have considerably complicated the simple textbook scheme of the peptide chain elongation cycle. During growth and differentiation the cycle may be regulated not only by factor modification but also factor replacement. In addition, rare tRNAs may have their own rare factor proteins. A special case is the acquisition of resistance by bacteria to elongation factor-directed antibiotics. Pertinent data from the literature and our own work with Escherichia coli and Streptomyces are discussed. The GTP-binding domain of EF-Tu has been studied extensively, but little molecular detail is available on the interactions with its other ligands or effectors, or on the way they are affected by the GTPase switch signal. A growing number of EF-Tu mutants obtained by ourselves and others are helping us in testing current ideas. We have found a synergistic effect between EF-Tu and EF-G in their uncoupled GTPase reactions on empty ribosomes. Only the EF-G reaction is perturbed by fluoroaluminates.
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Affiliation(s)
- B Kraal
- Department of Biochemistry, Leiden University, The Netherlands
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14
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Mazabraud A, Wegnez M, Denis H. Origin of several abundant proteins of amphibian oocytes. J Mol Evol 1992. [DOI: 10.1007/bf00160215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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15
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mRNP4, a major mRNA-binding protein from Xenopus oocytes is identical to transcription factor FRG Y2. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)49636-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Morales J, Mulner-Lorillon O, Denis H, Bellé R. Purification and characterization of a germ cell-specific form of elongation factor 1 alpha (EF-1 alpha) from Xenopus laevis. Biochimie 1991; 73:1249-53. [PMID: 1747390 DOI: 10.1016/0300-9084(91)90011-o] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Elongation factor 1 alpha (EF-1 alpha) was purified to homogeneity from full-grown oocytes of Xenopus laevis. This protein is encoded by a gene previously shown to be expressed in male and female germ cells, and repressed in somatic cells. The purified protein was identified with EF-1 alpha on criteria of molecular mass, cross-reaction with antibodies raised against Artemia salina EF-1 alpha, affinity for guanine nucleotides, and ability to promote the mRNA-dependent binding of aminoacyl tRNA to 80S ribosomes.
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Affiliation(s)
- J Morales
- Laboratoire de Physiologie de la Reproduction, Université P et M Curie, INRA, UA CNRS 1449, Paris, France
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