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Guay SY, Patel PH, Thomalla JM, McDermott KL, O'Toole JM, Arnold SE, Obrycki SJ, Wolfner MF, Findlay GD. A newly evolved gene is essential for efficient sperm entry into eggs in Drosophila melanogaster. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.08.607187. [PMID: 39149251 PMCID: PMC11326263 DOI: 10.1101/2024.08.08.607187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
New genes arise through a variety of evolutionary processes and provide raw material for adaptation in the face of both natural and sexual selection. De novo evolved genes emerge from previously non-protein-coding DNA sequences, and many such genes are expressed in male reproductive structures. In Drosophila melanogaster , several putative de novo genes have evolved essential roles in spermatogenesis, but whether such genes can also impact sperm function beyond the male has not been investigated. We identified a putative de novo gene, katherine johnson ( kj ), that is required for high levels of male fertility. Males that do not express kj produce and transfer sperm that are stored normally in females, but sperm from these males enter eggs with severely reduced efficiency. Using a tagged transgenic rescue construct, we observed that KJ protein localizes to the nuclear periphery in various stages of spermatogenesis, but is not detectable in mature sperm. These data suggest that kj exerts an effect on sperm development, the loss of which results in reduced fertilization ability. While previous bioinformatic analyses suggested the kj gene was restricted to the melanogaster group of Drosophila , we identified putative orthologs with conserved synteny, male-biased expression, and predicted protein features across the genus, as well as instances of gene loss in some lineages. Thus, kj potentially arose in the Drosophila common ancestor and subsequently evolved an essential role in D. melanogaster . Our results demonstrate a new aspect of male reproduction that has been shaped by new gene evolution and provide a molecular foothold for further investigating the mechanism of sperm entry into eggs in Drosophila . Article Summary How fruit fly sperm enter eggs is poorly understood. Here, we identify a gene that potentially arose from non-protein-coding DNA and is required for efficient fertilization. Sperm from males lacking this gene's function cannot enter eggs. The gene appears to act during sperm production, rather than in mature sperm. This study illustrates how newly evolved genes can affect important aspects of reproduction and provides insights into sperm-egg interactions.
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Yang WJ, Xu KK, Yan X, Li C. Knockdown of β- N-acetylglucosaminidase 2 Impairs Molting and Wing Development in Lasioderma serricorne (Fabricius). INSECTS 2019; 10:insects10110396. [PMID: 31717288 PMCID: PMC6921043 DOI: 10.3390/insects10110396] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/31/2019] [Accepted: 11/06/2019] [Indexed: 12/11/2022]
Abstract
β-N-acetylglucosaminidases (NAGs) are carbohydrate enzymes that degrade chitin oligosaccharides into N-acetylglucosamine monomers. This process is important for chitin degradation during insect development and metamorphosis. We identified and evaluated a β-N-acetylglucosaminidase 2 gene (LsNAG2) from the cigarette beetle, Lasioderma serricorne (Fabricius). The full-length open reading frame of LsNAG2 was 1776 bp and encoded a 591 amino acid protein. The glycoside hydrolase family 20 (GH20) catalytic domain and an additional GH20b domain of the LsNAG2 protein were highly conserved. Phylogenetic analysis revealed that LsNAG2 clustered with the group II NAGs. Quantitative real-time PCR analyses showed that LsNAG2 was expressed in all developmental stages and was most highly expressed in the late larval and late pupal stages. In the larval stage, LsNAG2 was predominantly expressed in the integument. Knockdown of LsNAG2 in fifth instar larvae disrupted larval-pupal molting and reduced the expression of four chitin synthesis genes (trehalase 1 (LsTRE1), UDP-N-acetylglucosamine pyrophosphorylase 1 and 2 (LsUAP1 and LsUAP2), and chitin synthase 1 (LsCHS1)). In late pupae, LsNAG2 depletion resulted in abnormal adult eclosion and wing deformities. The expression of five wing development-related genes (teashirt (LsTSH), vestigial (LsVG), wingless (LsWG), ventral veins lacking (LsVVL), and distal-less (LsDLL)) significantly declined in the LsNAG2-depleted beetles. These findings suggest that LsNAG2 is important for successful molting and wing development of L. serricorne.
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Affiliation(s)
| | | | | | - Can Li
- Correspondence: ; Tel.: +86-851-8540-5891
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3
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Tjondro HC, Loke I, Chatterjee S, Thaysen-Andersen M. Human protein paucimannosylation: cues from the eukaryotic kingdoms. Biol Rev Camb Philos Soc 2019; 94:2068-2100. [PMID: 31410980 DOI: 10.1111/brv.12548] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 07/10/2019] [Accepted: 07/17/2019] [Indexed: 12/11/2022]
Abstract
Paucimannosidic proteins (PMPs) are bioactive glycoproteins carrying truncated α- or β-mannosyl-terminating asparagine (N)-linked glycans widely reported across the eukaryotic domain. Our understanding of human PMPs remains limited, despite findings documenting their existence and association with human disease glycobiology. This review comprehensively surveys the structures, biosynthetic routes and functions of PMPs across the eukaryotic kingdoms with the aim of synthesising an improved understanding on the role of protein paucimannosylation in human health and diseases. Convincing biochemical, glycoanalytical and biological data detail a vast structural heterogeneity and fascinating tissue- and subcellular-specific expression of PMPs within invertebrates and plants, often comprising multi-α1,3/6-fucosylation and β1,2-xylosylation amongst other glycan modifications and non-glycan substitutions e.g. O-methylation. Vertebrates and protists express less-heterogeneous PMPs typically only comprising variable core fucosylation of bi- and trimannosylchitobiose core glycans. In particular, the Manα1,6Manβ1,4GlcNAc(α1,6Fuc)β1,4GlcNAcβAsn glycan (M2F) decorates various human neutrophil proteins reportedly displaying bioactivity and structural integrity demonstrating that they are not degradation products. Less-truncated paucimannosidic glycans (e.g. M3F) are characteristic glycosylation features of proteins expressed by human cancer and stem cells. Concertedly, these observations suggest the involvement of human PMPs in processes related to innate immunity, tumorigenesis and cellular differentiation. The absence of human PMPs in diverse bodily fluids studied under many (patho)physiological conditions suggests extravascular residence and points to localised functions of PMPs in peripheral tissues. Absence of PMPs in Fungi indicates that paucimannosylation is common, but not universally conserved, in eukaryotes. Relative to human PMPs, the expression of PMPs in plants, invertebrates and protists is more tissue-wide and constitutive yet, similar to their human counterparts, PMP expression remains regulated by the physiology of the producing organism and PMPs evidently serve essential functions in development, cell-cell communication and host-pathogen/symbiont interactions. In most PMP-producing organisms, including humans, the N-acetyl-β-hexosaminidase isoenzymes and linkage-specific α-mannosidases are glycoside hydrolases critical for generating PMPs via N-acetylglucosaminyltransferase I (GnT-I)-dependent and GnT-I-independent truncation pathways. However, the identity and structure of many species-specific PMPs in eukaryotes, their biosynthetic routes, strong tissue- and development-specific expression, and diverse functions are still elusive. Deep exploration of these PMP features involving, for example, the characterisation of endogenous PMP-recognising lectins across a variety of healthy and N-acetyl-β-hexosaminidase-deficient human tissue types and identification of microbial adhesins reactive to human PMPs, are amongst the many tasks required for enhanced insight into the glycobiology of human PMPs. In conclusion, the literature supports the notion that PMPs are significant, yet still heavily under-studied biomolecules in human glycobiology that serve essential functions and create structural heterogeneity not dissimilar to other human N-glycoprotein types. Human PMPs should therefore be recognised as bioactive glycoproteins that are distinctly different from the canonical N-glycoprotein classes and which warrant a more dedicated focus in glycobiological research.
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Affiliation(s)
- Harry C Tjondro
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia
| | - Ian Loke
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia.,Department of Biological Sciences, National University of Singapore, Singapore 117543, Singapore
| | - Sayantani Chatterjee
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia
| | - Morten Thaysen-Andersen
- Department of Molecular Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia
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Scheys F, Van Damme EJM, Smagghe G. Let’s talk about sexes: sex-related N-glycosylation in ecologically important invertebrates. Glycoconj J 2019; 37:41-46. [DOI: 10.1007/s10719-019-09866-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 03/15/2019] [Indexed: 11/30/2022]
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5
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Intra J, Veltri C, De Caro D, Perotti ME, Pasini ME. In vitro evidence for the participation of Drosophila melanogaster sperm β-N-acetylglucosaminidases in the interactions with glycans carrying terminal N-acetylglucosamine residues on the egg's envelopes. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2017; 96:e21403. [PMID: 28695569 DOI: 10.1002/arch.21403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fertilization is a complex and multiphasic process, consisting of several steps, where egg-coating envelope's glycoproteins and sperm surface receptors play a critical role. Sperm-associated β-N-acetylglucosaminidases, also known as hexosaminidases, have been identified in a variety of organisms. Previously, two isoforms of hexosaminidases, named here DmHEXA and DmHEXB, were found as intrinsic proteins in the sperm plasma membrane of Drosophila melanogaster. In the present work, we carried out different approaches using solid-phase assays in order to analyze the oligosaccharide recognition ability of D. melanogaster sperm hexosaminidases to interact with well-defined carbohydrate chains that might functionally mimic egg glycoconjugates. Our results showed that Drosophila hexosaminidases prefer glycans carrying terminal β-N-acetylglucosamine, but not core β-N-acetylglucosamine residues. The capacity of sperm β-N-acetylhexosaminidases to bind micropylar chorion and vitelline envelope was examined in vitro assays. Binding was completely blocked when β-N-acetylhexosaminidases were preincubated with the glycoproteins ovalbumin and transferrin, and the monosaccharide β-N-acetylglucosamine. Overall, these data support the hypothesis of the potential role of these glycosidases in sperm-egg interactions in Drosophila.
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Affiliation(s)
- Jari Intra
- Department of Biosciences, University of Milano, Milano, Italy
| | - Concetta Veltri
- Department of Biosciences, University of Milano, Milano, Italy
| | - Daniela De Caro
- Department of Biosciences, University of Milano, Milano, Italy
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6
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Intra J, Concetta V, Daniela DC, Perotti ME, Pasini ME. Drosophila sperm surface alpha-L-fucosidase interacts with the egg coats through its core fucose residues. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 63:133-143. [PMID: 26101846 DOI: 10.1016/j.ibmb.2015.06.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 06/17/2015] [Accepted: 06/18/2015] [Indexed: 06/04/2023]
Abstract
Sperm-oocyte interaction during fertilization is multiphasic, with multicomponent events, taking place between egg's glycoproteins and sperm surface receptors. Protein-carbohydrate complementarities in gamete recognition have observed in cases throughout the whole evolutionary scale. Sperm-associated α-L-fucosidases have been identified in various organisms. Their wide distribution and known properties reflect the hypothesis that fucose and α-L-fucosidases have fundamental function(s) during gamete interactions. An α-L-fucosidase has been detected as transmembrane protein on the surface of spermatozoa of eleven species across the genus Drosophila. Immunofluorescence labeling showed that the protein is localized in the sperm plasma membrane over the acrosome and the tail, in Drosophila melanogaster. In the present study, efforts were made to analyze with solid phase assays the oligosaccharide recognition ability of fruit fly sperm α-L-fucosidase with defined carbohydrate chains that can functionally mimic egg glycoconjugates. Our results showed that α-L-fucosidase bound to fucose residue and in particular it prefers N-glycans carrying core α1,6-linked fucose and core α1,3-linked fucose in N-glycans carrying only a terminal mannose residue. The ability of sperm α-L-fucosidase to bind to the micropylar chorion and to the vitelline envelope was examined in in vitro assays in presence of α-L-fucosidase, either alone or in combination with molecules containing fucose residues. No binding was detected when α-L-fucosidase was pre-incubated with fucoidan, a polymer of α-L-fucose and the monosaccharide fucose. Furthermore, egg labeling with anti-horseradish peroxidase, that recognized only core α1,3-linked fucose, correlates with α-L-fucosidase micropylar binding. Collectively, these data support the hypothesis of the potential role of this glycosidase in sperm-egg interactions in Drosophila.
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Affiliation(s)
- Jari Intra
- Department of Biosciences, University of Milano, via Celoria 26, Milano 20133, Italy.
| | - Veltri Concetta
- Department of Biosciences, University of Milano, via Celoria 26, Milano 20133, Italy
| | - De Caro Daniela
- Department of Biosciences, University of Milano, via Celoria 26, Milano 20133, Italy
| | - Maria Elisa Perotti
- Department of Biosciences, University of Milano, via Celoria 26, Milano 20133, Italy
| | - Maria Enrica Pasini
- Department of Biosciences, University of Milano, via Celoria 26, Milano 20133, Italy
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Stephens K, Thaler CD, Cardullo RA. Characterization of plasma membrane associated type II α-D-mannosidase and β-N-acetylglucosaminidase of Aquarius remigis sperm. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2015; 60:78-85. [PMID: 25801709 DOI: 10.1016/j.ibmb.2015.03.004] [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] [Received: 01/19/2015] [Revised: 02/25/2015] [Accepted: 03/10/2015] [Indexed: 06/04/2023]
Abstract
For successful fertilization to occur, molecules on the surface of male and female gametes must recognize each other in a complementary manner. In some organisms, sperm possess a glycosidase on the plasma membrane overlying the head while eggs have glycoproteins that are recognized by those glycosidases resulting in sperm-egg recognition. In this study, two glycosidases, mannosidase and β-N-acetylglucosaminidase, were identified and biochemically characterized in Aquarius remigis sperm. The mannosidase had a Km of 2.36 ± 0.19 mM, a Vmax of 27.49 ± 0.88 pmol/min and a Hill coefficient of 0.94 ± 0.18 at its optimal pH of 7.0. The mannosidase was extracted most efficiently with CHAPSO but was also efficiently extracted with sodium chloride. Mannosidase activity was effectively inhibited by swainsonine, but not by kifunesine, and was significantly reduced in the presence of Mn(2+) and Mg(2+), but not Zn(2+). N-acetylglucosaminidase had a Km of 0.093 ± 0.01 mM, a Vmax of 153.80 ± 2.97 pmol/min and a Hill coefficient of 0.96 ± 0.63 at its optimal pH of 7.0. N-acetylglucosaminidase was extracted most efficiently with potassium iodide but was also efficiently extracted with Triton X-100 and Zn(2+), but not Ca(2+), Co(2+), Mn(2+) or Mg(2+), significantly inhibited its activity. Taken together, these results indicate that the A. remigis sperm surface contains at least two glycosidases that may recognize complementary glycoconjugates on the surface of water strider eggs.
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Affiliation(s)
- Kimberly Stephens
- Department of Entomology, University of California, Riverside, CA 92521, USA
| | - Catherine D Thaler
- Department of Biology, University of California, Riverside, CA 92521, USA
| | - Richard A Cardullo
- Department of Entomology, University of California, Riverside, CA 92521, USA; Department of Biology, University of California, Riverside, CA 92521, USA.
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Nomura T, Suganuma M, Higa Y, Kataoka Y, Funaguma S, Okazaki H, Suzuki T, Kobayashi I, Sezutsu H, Fujiyama K. Improvement of glycosylation structure by suppression of β-N-acetylglucosaminidases in silkworm. J Biosci Bioeng 2014; 119:131-6. [PMID: 25193875 DOI: 10.1016/j.jbiosc.2014.07.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 07/23/2014] [Accepted: 07/31/2014] [Indexed: 11/29/2022]
Abstract
The baculovirus-silkworm recombinant protein expression system is an excellent method for achieving high-level expression and post-translational modifications, especially glycosylation. However, the presence of paucimannosidic-type N-glycan in glycoproteins restricts their clinical use. Paucimannosidic-type N-glycan is produced by insect-specific membrane-binding-type β-N-acetylglucosaminidase (GlcNAcase). In the silkworm, BmGlcNAcase1, BmGlcNAcase2, and BmFDL are membrane-binding-type GlcNAcases. We investigated the localization of these GlcNAcases and found that BmFDL and BmGlcNAcase2 were mainly located in the fat body and hemolymph, respectively. The fat body is the main tissue of recombinant protein expression by baculovirus, and many glycoproteins are secreted into the hemolymph. These results suggest that inhibition of BmFDL and BmGlcNAcase2 could increase GlcNAc-type N-glycan levels. We therefore injected a GlcNAcase inhibitor into silkworms to investigate changes in the N-glycan structure of the glycoprotein expressed by baculovirus; modest levels of GlcNAc-type N-glycan were observed (0.8% of total N-glycan). Next, we generated a transgenic silkworm in which RNA interference (RNAi) reduced the BmFDL transcript level and enzyme activity to 25% and 50%, respectively, of that of the control silkworm. The proportion of GlcNAc-type N-glycan increased to 4.3% in the RNAi-transgenic silkworm. We conclude that the structure of N-glycan can be changed by inhibiting the GlcNAcases in silkworm.
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Affiliation(s)
- Tsuyoshi Nomura
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan; The International Center for Biotechnology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-8071, Japan.
| | - Masatoshi Suganuma
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan
| | - Yukiko Higa
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan
| | - Yukiko Kataoka
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan
| | - Shunsuke Funaguma
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan
| | - Hironobu Okazaki
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan
| | - Takeo Suzuki
- Protein Development Center, Sysmex Corporation, 1548 Simo-okudomi, Sayama, Saitama 350-1332, Japan
| | - Isao Kobayashi
- Transgenic Silkworm Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Hideki Sezutsu
- Transgenic Silkworm Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, 1-2 Owashi, Tsukuba, Ibaraki 305-8634, Japan
| | - Kazuhito Fujiyama
- The International Center for Biotechnology, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-8071, Japan
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9
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The expression profile and promoter analysis of β-N-acetylglucosaminidases in the silkworm Bombyx mori. Mol Biol Rep 2014; 41:6667-78. [PMID: 25001591 DOI: 10.1007/s11033-014-3550-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 06/20/2014] [Indexed: 10/25/2022]
Abstract
β-N-acetylglucosaminidase (GlcNAcase) is a key enzyme in the chitin decomposition process. In this study, we investigated the gene expression profile of GlcNAcases and the regulation mechanism for one of these genes, BmGlcNAcase1, in the silkworm. We performed sequence analysis of GlcNAcase. Using dual-spike-in qPCR method, we examined the expression of Bombyx β-N-acetylglucosaminidases (BmGlcNAcases) in various tissues of silkworm as well as expression changes after stimulation with ecdysone. Using Bac-to-Bac system and luciferase reporter vectors, we further analyzed the promoter sequence of BmGlcNAcase1. The results showed that these proteins have a highly conserved catalytic domain. The expression levels of the BmGlcNAcase genes varied in different tissues, and were increased 48 h after exposure to ecdysone. BmGlcNAcase1 gene promoter with 5'-end serial deletions showed different levels of activity in various tissues, higher in the blood, skin and fat body. Deletion of the region from -347 to -223 upstream of BmGlcNAcase-1 gene abolished its promoter activity. This region contains the binding sites for key transcription factors including Hb, BR-C Z, the HSF and the typical TATA-box element. These results indicate that BmGlcNAcases are expressed at different levels in different tissues of the silkworm, but all are subjected to the regulation by ecdysone. BmGlcNAcase1 promoter analysis has paved a foundation for further study of the gene expression patterns.
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Ryazansky SS, Mikhaleva EA, Olenkina OV. Essential functions of microRNAs in animal reproductive organs. Mol Biol 2014. [DOI: 10.1134/s0026893314030182] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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11
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Rosenbaum EE, Vasiljevic E, Brehm KS, Colley NJ. Mutations in four glycosyl hydrolases reveal a highly coordinated pathway for rhodopsin biosynthesis and N-glycan trimming in Drosophila melanogaster. PLoS Genet 2014; 10:e1004349. [PMID: 24785692 PMCID: PMC4006722 DOI: 10.1371/journal.pgen.1004349] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 03/18/2014] [Indexed: 01/16/2023] Open
Abstract
As newly synthesized glycoproteins move through the secretory pathway, the asparagine-linked glycan (N-glycan) undergoes extensive modifications involving the sequential removal and addition of sugar residues. These modifications are critical for the proper assembly, quality control and transport of glycoproteins during biosynthesis. The importance of N-glycosylation is illustrated by a growing list of diseases that result from defects in the biosynthesis and processing of N-linked glycans. The major rhodopsin in Drosophila melanogaster photoreceptors, Rh1, is highly unique among glycoproteins, as the N-glycan appears to be completely removed during Rh1 biosynthesis and maturation. However, much of the deglycosylation pathway for Rh1 remains unknown. To elucidate the key steps in Rh1 deglycosylation in vivo, we characterized mutant alleles of four Drosophila glycosyl hydrolases, namely α-mannosidase-II (α-Man-II), α-mannosidase-IIb (α-Man-IIb), a β-N-acetylglucosaminidase called fused lobes (Fdl), and hexosaminidase 1 (Hexo1). We have demonstrated that these four enzymes play essential and unique roles in a highly coordinated pathway for oligosaccharide trimming during Rh1 biosynthesis. Our results reveal that α-Man-II and α-Man-IIb are not isozymes like their mammalian counterparts, but rather function at distinct stages in Rh1 maturation. Also of significance, our results indicate that Hexo1 has a biosynthetic role in N-glycan processing during Rh1 maturation. This is unexpected given that in humans, the hexosaminidases are typically lysosomal enzymes involved in N-glycan catabolism with no known roles in protein biosynthesis. Here, we present a genetic dissection of glycoprotein processing in Drosophila and unveil key steps in N-glycan trimming during Rh1 biosynthesis. Taken together, our results provide fundamental advances towards understanding the complex and highly regulated pathway of N-glycosylation in vivo and reveal novel insights into the functions of glycosyl hydrolases in the secretory pathway.
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Affiliation(s)
- Erica E. Rosenbaum
- Department of Ophthalmology & Visual Sciences and Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Eva Vasiljevic
- Department of Ophthalmology & Visual Sciences and Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Kimberley S. Brehm
- Department of Ophthalmology & Visual Sciences and Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Nansi Jo Colley
- Department of Ophthalmology & Visual Sciences and Department of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
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Majewska MM, Suszczynska A, Kotwica-Rolinska J, Czerwik T, Paterczyk B, Polanska MA, Bernatowicz P, Bebas P. Yolk proteins in the male reproductive system of the fruit fly Drosophila melanogaster: spatial and temporal patterns of expression. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 47:23-35. [PMID: 24556521 DOI: 10.1016/j.ibmb.2014.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/30/2014] [Accepted: 02/05/2014] [Indexed: 06/03/2023]
Abstract
In insects, spermatozoa develop in the testes as clones of single spermatogonia covered by specialized somatic cyst cells (cc). Upon completion of spermatogenesis, spermatozoa are released to the vas deferens, while the cc remain in the testes and die. In the fruit fly Drosophila melanogaster, the released spermatozoa first reach the seminal vesicles (SV), the organ where post-testicular maturation begins. Here, we demonstrate the temporal (restricted to the evening and early night hours) accumulation of membranous vesicles containing proteins in the SV lumen of D. melanogaster. When SV vesicles were isolated from the semen and co-incubated with testis-derived spermatozoa in vitro, their contents bound to the spermatozoa along their tails. The proteins of the SV vesicles were then characterized using 2-D electrophoresis. We identified a prominent protein spot of around 45-47 kDa, which disappears from the SV vesicles in the night, i.e. shortly after they appear in the SV lumen. Sequencing of peptides derived from this spot by mass spectrometry revealed identity with three yolk proteins (YP1-3). This unexpected result was confirmed by western blotting, which demonstrated that SV vesicles contain proteins that are immunoreactive with an antibody against D. melanogaster YP1-3. The expression of all yp genes was shown to be a unique feature of testis tissues. Using RNA probes we found that their transcripts localize exclusively to the cc that cover fully developed spermatozoa in the distal part of each testis. Temporally, the expression of yp genes was found to be restricted to a short period during the day and is followed by the evening accumulation of YP proteins in the cc. Immunohistochemical staining confirmed that cc are the source of SV vesicles containing YPs that are released into the SV lumen. These vesicles interact with spermatozoa and as a result, YPs become extrinsic proteins of the sperm membrane. Thus, we describe for the first time the expression of yolk proteins in the male reproductive system of D. melanogaster under physiological conditions, and show that somatic cells of the testes are the source of these proteins.
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Affiliation(s)
- Magdalena M Majewska
- Department of Animal Physiology, Zoological Institute, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
| | - Agnieszka Suszczynska
- Department of Animal Physiology, Zoological Institute, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
| | - Joanna Kotwica-Rolinska
- Department of Animal Physiology, Zoological Institute, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
| | - Tomasz Czerwik
- Department of Animal Physiology, Zoological Institute, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
| | - Bohdan Paterczyk
- Laboratory of Electron and Confocal Microscopy, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
| | - Marta A Polanska
- Department of Animal Physiology, Zoological Institute, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
| | - Piotr Bernatowicz
- Department of Paleobiology and Evolution, Faculty of Biology, University of Warsaw, CNBC (Cent 3), 101 Zwirki i Wigury Str., 02-089 Warsaw, Poland.
| | - Piotr Bebas
- Department of Animal Physiology, Zoological Institute, Faculty of Biology, University of Warsaw, 1 Miecznikowa Str., 02-096 Warsaw, Poland.
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13
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Qu M, Liu T, Chen P, Yang Q. A sperm-plasma β-N-acetyl-D-hexosaminidase interacting with a Chitinolytic β-N-Acetyl-D-hexosaminidase in insect molting fluid. PLoS One 2013; 8:e71738. [PMID: 23951233 PMCID: PMC3741120 DOI: 10.1371/journal.pone.0071738] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Accepted: 07/03/2013] [Indexed: 11/25/2022] Open
Abstract
Insects require molting fluids to shed the old cuticle during molting. β-N-acetyl-D-hexosaminidase, known as Hex1, together with various chitinases, is responsible for degrading the chitin component of the old cuticle. This study showed that another β-N-acetyl-D-hexosaminidase, termed OfHex3, interacted with Hex1 and functioned in the molting fluid, although the homolog of OfHex3 was known as a sperm–plasma enzyme functioning in egg–sperm recognition. OfHex3 is an enzyme cloned from the insect Asian corn borer, Ostrinia furnacalis, which is one of the most destructive pests of maize. The enzymatic activity analysis indicated that OfHex3 was able to degrade chitooligosaccharides, but at a lower rate than that of OfHex1. Because OfHex3 did not have substrate inhibition, we deduced that the presence of OfHex3 might help OfHex1 relieve substrate inhibition during chitin degradation during molting. The expression patterns of OfHex3 during O. furnacalis development were studied by real-time PCR as well as western blot. The results showed that both gene transcription and protein translation levels of OfHex3 were up-regulated during larval–larval molting. The tissue-specific expression pattern analysis indicated that OfHex3 was mostly localized in the fat body and testis. All these data further supported that Hex3 was involved in molting as well as in fertilization. This study may help to understand the complexity of cuticle degradation during insect molting, and may provide a possible target for pest control.
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Affiliation(s)
- Mingbo Qu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, China
| | - Tian Liu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, China
| | - Peng Chen
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, China
| | - Qing Yang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, China
- * E-mail:
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14
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β-Hexosaminidase over-expression affects lysosomal glycohydrolases expression and glycosphingolipid metabolism in mammalian cells. Mol Cell Biochem 2011; 363:109-18. [DOI: 10.1007/s11010-011-1163-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 11/23/2011] [Indexed: 10/14/2022]
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15
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Liu T, Zhang H, Liu F, Wu Q, Shen X, Yang Q. Structural determinants of an insect beta-N-Acetyl-D-hexosaminidase specialized as a chitinolytic enzyme. J Biol Chem 2010; 286:4049-58. [PMID: 21106526 DOI: 10.1074/jbc.m110.184796] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
β-N-acetyl-D-hexosaminidase has been postulated to have a specialized function. However, the structural basis of this specialization is not yet established. OfHex1, the enzyme from the Asian corn borer Ostrinia furnacalis (one of the most destructive pests) has previously been reported to function merely in chitin degradation. Here the vital role of OfHex1 during the pupation of O. furnacalis was revealed by RNA interference, and the crystal structures of OfHex1 and OfHex1 complexed with TMG-chitotriomycin were determined at 2.1 Å. The mechanism of selective inhibition by TMG-chitotriomycin was related to the existence of the +1 subsite at the active pocket of OfHex1 and a key residue, Trp(490), at this site. Mutation of Trp(490) to Ala led to a 2,277-fold decrease in sensitivity toward TMG-chitotriomycin as well as an 18-fold decrease in binding affinity for the substrate (GlcNAc)(2). Although the overall topology of the catalytic domain of OfHex1 shows a high similarity with the human and bacterial enzymes, OfHex1 is distinguished from these enzymes by large conformational changes linked to an "open-close" mechanism at the entrance of the active site, which is characterized by the "lid" residue, Trp(448). Mutation of Trp(448) to Ala or Phe resulted in a more than 1,000-fold loss in enzyme activity, due mainly to the effect on k(cat). The current work has increased our understanding of the structure-function relationship of OfHex1, shedding light on the structural basis that accounts for the specialized function of β-N-acetyl-D-hexosaminidase as well as making the development of species-specific pesticides a likely reality.
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Affiliation(s)
- Tian Liu
- Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian 116024, China
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16
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Pasini ME, Intra J, Gomulski LM, Calvenzani V, Petroni K, Briani F, Perotti ME. Identification and expression profiling of Ceratitis capitata genes coding for β-hexosaminidases. Gene 2010; 473:44-56. [PMID: 21094225 DOI: 10.1016/j.gene.2010.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 11/05/2010] [Accepted: 11/08/2010] [Indexed: 10/18/2022]
Abstract
The goal of this study was to identify the genes coding for β-N-acetylhexosaminidases in the Mediterranean fruit fly (medfly) Ceratitis capitata, one of the most destructive agricultural pests, belonging to the Tephritidae family, order Diptera. Two dimeric β-N-acetylhexosaminidases, HEXA and HEXB, have been recently identified on Drosophila sperm. These enzymes are involved in egg binding through interactions with complementary carbohydrates on the surface of the egg shell. Three genes, Hexosaminidase 1 (Hexo1), Hexosaminidase 2 (Hexo2) and fused lobes (fdl), encode for HEXA and HEXB subunits. The availability of C. capitata EST libraries derived from embryos and adult heads allowed us to identify three sequences homologous to the D. melanogaster Hexo1, Hexo2 and fdl genes. Here, we report the expression profile analysis of CcHexo1, CcHexo2 and Ccfdld in several tissues, organs and stages. Ccfdl expression was highest in heads of both sexes and in whole adult females. In the testis and ovary the three genes showed distinct spatial and temporal expression patterns. All the mRNAs were detectable in early stages of spermatogenesis; CcHexo2 and Ccfdl were also expressed in early elongating spermatid cysts. All three genes are expressed in the ovarian nurse cells. CcHexo1 and Ccfdl are stage specific, since they have been observed in stages 12 and 13 during oocyte growth, when programmed cell death occurs in nurse cells. The expression pattern of the three genes in medfly gonads suggests that, as their Drosophila counterparts, they may encode for proteins involved in gametogenesis and fertilization.
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Affiliation(s)
- Maria E Pasini
- Department of Biomolecular Sciences and Biotechnology, University of Milano, Milano, Italy.
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17
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Nomura T, Ikeda M, Ishiyama S, Mita K, Tamura T, Okada T, Fujiyama K, Usami A. Cloning and characterization of a β-N-acetylglucosaminidase (BmFDL) from silkworm Bombyx mori. J Biosci Bioeng 2010; 110:386-91. [PMID: 20547376 DOI: 10.1016/j.jbiosc.2010.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 04/15/2010] [Accepted: 04/20/2010] [Indexed: 10/19/2022]
Abstract
In insects, β-N-acetylglucosaminidase (GlcNAcase) participates in critical physiological processes such as fertilization, metamorphosis, and glycoconjugate degradation. Insects produce glycoproteins carrying paucimannosidic-type N-glycans, the terminal GlcNAc residue of which is cleaved by a GlcNAc-linkage specific GlcNAcase, also known as the fused lobes (FDL) protein. To obtain information on the structure of GlcNAcases and insight into their contribution to physiological processes, we cloned Bombyx mori FDL (BmFDL) from silkworm larvae. The full-length cDNA (1.9 kb) encoded a protein of 633 amino acids with 42% amino acid sequence identity to Drosophila melanogaster FDL (DmFDL). Recombinant BmFDL cleaved only β-1,2-linked GlcNAc residues from the α-1,3 branch of biantennary N-glycan. This substrate specificity was similar to that of DmFDL. Microsomal FDL activity was inhibited by anti-BmFDL antibodies. Taken together, our results suggest that BmFDL is a N-glycan-processing GlcNAcase in B. mori.
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Affiliation(s)
- Tsuyoshi Nomura
- Research Institute of Biological Science, Katakura industries CO., LTD., 1548 Simo-okutomi, Sayama, Saitama 350-1332, Japan.
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18
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Prokupek AM, Eyun SI, Ko L, Moriyama EN, Harshman LG. Molecular evolutionary analysis of seminal receptacle sperm storage organ genes of Drosophila melanogaster. J Evol Biol 2010; 23:1386-98. [PMID: 20500366 DOI: 10.1111/j.1420-9101.2010.01998.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Sperm storage organs are common and broadly distributed among animal taxa. However, little is known about how these organs function at the molecular level. Additionally, there is a paucity of knowledge about the evolution of genes expressed in these organs. This investigation is an evolutionary expressed sequence tag (EST) study of genes expressed in the seminal receptacle, one of the sperm storage organs in Drosophila. The incidence of positive selection is higher for the seminal receptacle genes than Drosophila reproductive genes as a whole, but lower than genes associated with the spermatheca, a second type of Drosophila sperm storage organ. By identifying overrepresented classes of proteins and classes for which sperm storage function is suggested by the nature of the proteins, candidate genes were discovered. These candidates belong to protein classes such as muscle contraction, odorant binding and odorant receptor, protease inhibitor and immunity.
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Affiliation(s)
- A M Prokupek
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68588, USA
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19
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Purification and Characterization of a Liver-derived β-N-Acetylhexosaminidase from Marine Mammal Sotalia fluviatilis. Protein J 2010; 29:188-94. [DOI: 10.1007/s10930-010-9239-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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20
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Liu T, Liu F, Yang Q, Yang J. Expression, purification and characterization of the chitinolytic β-N-acetyl-d-hexosaminidase from the insect Ostrinia furnacalis. Protein Expr Purif 2009; 68:99-103. [DOI: 10.1016/j.pep.2009.06.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 06/03/2009] [Accepted: 06/03/2009] [Indexed: 10/20/2022]
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21
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Identification and characterization of mature β-hexosaminidases associated with human placenta lysosomal membrane. Biosci Rep 2008; 28:229-37. [DOI: 10.1042/bsr20080075] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Hex (β-hexosaminidase) is a soluble glycohydrolase involved in glycoconjugate degradation in lysosomes, however its localization has also been described in the cytosol and PM (plasma membrane). We previously demonstrated that Hex associated with human fibroblast PM as the mature form, which is functionally active towards GM2 ganglioside. In the present study, Hex was analysed in a lysosomal membrane-enriched fraction obtained by purification from highly purified human placenta lysosomes. These results demonstrate the presence of mature Hex associated with the lysosomal membrane and displaying, as observed for the PM-associated form, an acidic optimum pH. When subjected to sodium carbonate extraction, the enzyme behaved as a peripheral membrane protein, whereas Triton X-114 phase separation confirmed its partially hydrophilic nature, characteristics which are shared with the PM-associated form of Hex. Moreover, two-dimensional electrophoresis indicated a slight difference in the pI of β-subunits in the membrane and the soluble forms of the lysosomal Hex. These results reveal a new aspect of Hex biology and suggest that a fully processed membrane-associated form of Hex is translocated from the lysosomal membrane to the PM by an as yet unknown mechanism. We present a testable hypothesis that, at the cell surface, Hex changes the composition of glycoconjugates that are known to be involved in intercellular communication and signalling.
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22
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Intra J, Pavesi G, Horner DS. Phylogenetic analyses suggest multiple changes of substrate specificity within the glycosyl hydrolase 20 family. BMC Evol Biol 2008; 8:214. [PMID: 18647384 PMCID: PMC2492878 DOI: 10.1186/1471-2148-8-214] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 07/22/2008] [Indexed: 12/14/2022] Open
Abstract
Background Beta-N-acetylhexosaminidases belonging to the glycosyl hydrolase 20 (GH20) family are involved in the removal of terminal β-glycosidacally linked N-acetylhexosamine residues. These enzymes, widely distributed in microorganisms, animals and plants, are involved in many important physiological and pathological processes, such as cell structural integrity, energy storage, pathogen defence, viral penetration, cellular signalling, fertilization, development of carcinomas, inflammatory events and lysosomal storage diseases. Nevertheless, only limited analyses of phylogenetic relationships between GH20 genes have been performed until now. Results Careful phylogenetic analyses of 233 inferred protein sequences from eukaryotes and prokaryotes reveal a complex history for the GH20 family. In bacteria, multiple gene duplications and lineage specific gene loss (and/or horizontal gene transfer) are required to explain the observed taxonomic distribution. The last common ancestor of extant eukaryotes is likely to have possessed at least one GH20 family member. At least one gene duplication before the divergence of animals, plants and fungi as well as other lineage specific duplication events have given rise to multiple paralogous subfamilies in eukaryotes. Phylogenetic analyses also suggest that a second, divergent subfamily of GH20 family genes present in animals derive from an independent prokaryotic source. Our data suggest multiple convergent changes of functional roles of GH20 family members in eukaryotes. Conclusion This study represents the first detailed evolutionary analysis of the glycosyl hydrolase GH20 family. Mapping of data concerning physiological function of GH20 family members onto the phylogenetic tree reveals that apparently convergent and highly lineage specific changes in substrate specificity have occurred in multiple GH20 subfamilies.
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Affiliation(s)
- Jari Intra
- Dipartimento di Scienze Biomolecolari e Biotecnologie, Università di Milano, Via Celoria 26, 20133 Milano, Italy.
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23
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Bebas P, Kotwica J, Joachimiak E, Giebultowicz JM. Yolk protein is expressed in the insect testis and interacts with sperm. BMC DEVELOPMENTAL BIOLOGY 2008; 8:64. [PMID: 18549506 PMCID: PMC2440742 DOI: 10.1186/1471-213x-8-64] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Accepted: 06/13/2008] [Indexed: 12/02/2022]
Abstract
Background Male and female gametes follow diverse developmental pathways dictated by their distinct roles in fertilization. While oocytes of oviparous animals accumulate yolk in the cytoplasm, spermatozoa slough off most of their cytoplasm in the process of individualization. Mammalian spermatozoa released from the testis undergo extensive modifications in the seminal ducts involving a variety of glycoproteins. Ultrastructural studies suggest that glycoproteins are involved in sperm maturation in insects; however, their characterization at the molecular level is lacking. We reported previously that the circadian clock controls sperm release and maturation in several insect species. In the moth, Spodoptera littoralis, the secretion of glycoproteins into the seminal fluid occurs in a daily rhythmic pattern. The purpose of this study was to characterize seminal fluid glycoproteins in this species and elucidate their role in the process of sperm maturation. Results We collected seminal fluid proteins from males before and after daily sperm release. These samples were separated by 2-D gel electrophoresis, and gels were treated with a glycoprotein-detecting probe. We observed a group of abundant glycoproteins in the sample collected after sperm release, which was absent in the sample collected before sperm release. Sequencing of these glycoproteins by mass spectroscopy revealed peptides bearing homology with components of yolk, which is known to accumulate in developing oocytes. This unexpected result was confirmed by Western blotting demonstrating that seminal fluid contains protein immunoreactive to antibody against yolk protein YP2 produced in the follicle cells surrounding developing oocytes. We cloned the fragment of yp2 cDNA from S. littoralis and determined that it is expressed in both ovaries and testes. yp2 mRNA and YP2 protein were detected in the somatic cyst cells enveloping sperm inside the testis. During the period of sperm release, YP2 protein appears in the seminal fluid and forms an external coat on spermatozoa. Conclusion One of the yolk protein precursors YP2, which in females accumulate in the oocytes to provision developing embryos, appears to have a second male-specific role. It is produced in the testes and released into the seminal fluid where it interacts with sperm. These data reveal unexpected common factor in the maturation of insect eggs and sperm.
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Affiliation(s)
- Piotr Bebas
- Department of Animal Physiology, Faculty of Biology, University of Warsaw, Warsaw, Poland.
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24
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Intra J, Cenni F, Pavesi G, Pasini M, Perotti ME. Interspecific analysis of the glycosidases of the sperm plasma membrane inDrosophila. Mol Reprod Dev 2008; 76:85-100. [DOI: 10.1002/mrd.20932] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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25
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Oluyinka OO, Mairo IH, Ajanusi JA, David O, Sekoni V, Nok AJ. Semen sialic acid surge and modulation of alpha-L-fucosidase activity: possible link to loss in reproductive capacity during trypanosomiasis. Cell Biochem Funct 2007; 26:154-61. [PMID: 17487932 DOI: 10.1002/cbf.1415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The profiles of semen sialic acid and the enzyme alpha-L-fucosidase were studied in rams undergoing chronic infection by Trypanosoma congolense. Our data showed a significant surge in the level of sialic acid with parasitaemia. The pattern followed a polynomial function we had reported for erythrocyte sialic acid in mice undergoing acute infection by T. congolense. The activity of the enzyme alpha-fucosidase decreased progressively with approximately 60% decrease at the end of the 14 weeks of infection. Representative semen samples from the control and infected rams were subjected to kinetic characterization. While the uninfected semen sample showed two active pH peaks at 4.5-5.5 and at 6.8-7.2, respectively, there was an apparent shift to only a single pH optimum at 4.5-5.5 for the pathological semen. The fucosidases from both sources were optimally active at 35 degrees C albeit with contrasting activation energies (E(a)) with values 20.58 and 35 kJ/mol for the control and infected semen, respectively. Kinetic studies using methylumbelliferyl-beta-fucoside (4MU-Fuc) as substrate gave K(M) and V(max) values of 3.25 microM and 14.6 micromol. min(-1) mg(-1), respectively for the control semen. The values for the infected semen were 18.25 microM and 10.5 micromol. min(-1) mg(-1), respectively. The significance of these results is discussed as they relate to loss in reproductive capacity in trypanosomoses.
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Affiliation(s)
- Okubanjo O Oluyinka
- Department of Veterinary Parasitology and Entomology, Ahmadu Bello University, Zaria, Nigeria
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26
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Léonard R, Rendic D, Rabouille C, Wilson IBH, Préat T, Altmann F. The Drosophila fused lobes Gene Encodes an N-Acetylglucosaminidase Involved in N-Glycan Processing. J Biol Chem 2006; 281:4867-75. [PMID: 16339150 DOI: 10.1074/jbc.m511023200] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Most processed, e.g. fucosylated, N-glycans on insect glycoproteins terminate in mannose, yet the relevant modifying enzymes require the prior action of N-acetylglucosaminyltransferase I. This led to the hypothesis that a hexosaminidase acts during the course of N-glycan maturation. To determine whether the Drosophila melanogaster genome indeed encodes such an enzyme, a cDNA corresponding to fused lobes (fdl), a putative beta-N-acetylglucosaminidase with a potential transmembrane domain, was cloned. When expressed in Pichia pastoris, the enzyme exhibited a substrate specificity similar to that previously described for a hexosaminidase activity from Sf-9 cells, i.e. it hydrolyzed exclusively the GlcNAc residue attached to the alpha1,3-linked mannose of the core pentasaccharide of N-glycans. It also hydrolyzed p-nitrophenyl-N-acetyl-beta-glucosaminide, but not chitooligosaccharides; in contrast, Drosophila HEXO1 and HEXO2 expressed in Pichia cleaved both these substrates but not N-glycans. The localization of recombinant FDL tagged with green fluorescent protein in Drosophila S2 cells by immunoelectron microscopy showed that this enzyme transits through the Golgi, is present on the plasma membrane and in multivesicular bodies, and is secreted. Finally, the N-glycans of two lines of fdl mutant flies were analyzed by mass spectrometry and reversed-phase high-performance liquid chromatography. The ratio of structures with terminal GlcNAc over those without (i.e. paucimannosidic N-glycans) was drastically increased in the fdl-deficient flies. Therefore, we conclude that the fdl gene encodes a novel hexosaminidase responsible for the occurrence of paucimannosidic N-glycans in Drosophila.
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Affiliation(s)
- Renaud Léonard
- Glycobiology Group, Department of Chemistry, University of Natural Resources and Applied Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria.
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Intra J, Cenni F, Perotti ME. An α-L-fucosidase potentially involved in fertilization is present onDrosophila spermatozoa surface. Mol Reprod Dev 2006; 73:1149-58. [PMID: 16736526 DOI: 10.1002/mrd.20425] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Drosophila is emerging as a model organism to investigate egg fertilization in insects and the possible conservation of molecular mechanisms of gamete interactions demonstrated in higher organisms. This study shows that the spermatozoa of several species of Drosophila belonging to the melanogaster group have a plasma membrane associated alpha-L-fucosidase with features in common with alpha-L-fucosidases from sperm of other animals, including mammals. The enzyme has been purified and completely characterized in D. ananassae, because of its stability in this species. The sperm alpha-L-fucosidase is an integral protein terminally mannosylated, with the catalytic site oriented toward the extracellular space. It has a M(r) of 256 kDa and a multimeric structure made up by subunits of 48 and 55 kDa. Enzyme characterization included kinetic properties, pI, optimal pH, and thermal stability. A soluble form of the enzyme similar to the sperm associated alpha-L-fucosidase is secreted by the seminal vesicles. Synthetic peptides designed from the deduced product of the D. melanogaster gene encoding an alpha-L-fucosidase were used to raise a specific polyclonal antibody. Immunofluorescence labeling of spermatozoa showed that the enzyme is present in the sperm plasma membrane overlying the acrosome and the tail. Lectin cytochemistry analysis of the egg surface indicated that alpha-L-fucose terminal residues are present on the chorion with a strongly polarized localization on the micropyle. The alpha-L-fucosidase of Drosophila sperm plasma membrane appears to be potentially involved in gamete recognition by interacting with its glycoside ligands present on the egg surface at the site of sperm entry.
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Affiliation(s)
- Jari Intra
- Department of Biomolecular Sciences and Biotechnologies, University of Milano, Milano, Italy
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28
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Aumiller JJ, Hollister JR, Jarvis DL. Molecular cloning and functional characterization of beta-N-acetylglucosaminidase genes from Sf9 cells. Protein Expr Purif 2005; 47:571-90. [PMID: 16427309 PMCID: PMC1592231 DOI: 10.1016/j.pep.2005.11.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2005] [Revised: 11/22/2005] [Accepted: 11/30/2005] [Indexed: 11/25/2022]
Abstract
Sf9, a cell line derived from the lepidopteran insect, Spodoptera frugiperda, is widely used as a host for recombinant glycoprotein expression and purification by baculovirus vectors. Previous studies have shown that this cell line has one or more beta-N-acetylglucosaminidase activities that may be involved in the degradation and/or processing of N-glycoprotein glycans. However, these enzymes and their functions remain poorly characterized. Therefore, the goal of this study was to isolate beta-N-acetylglucosaminidase genes from Sf9 cells, over-express the gene products, and characterize their enzymatic activities. A degenerate PCR approach yielded three Sf9 cDNAs, which appeared to encode two distinct beta-N-acetylglucosaminidases, according to bioinformatic analyses. Baculovirus-mediated expression of these two cDNA products induced membrane-associated beta-N-acetylglucosaminidase activities in Sf9 cells, which cleaved terminal N-acetylglucosamine residues from the alpha-3 and -6 branches of a biantennary N-glycan substrate with acidic pH optima and completely hydrolyzed chitotriose to its constituent N-acetylglucosamine monomers. GFP-tagged forms of both enzymes exhibited punctate cytoplasmic fluorescence, which did not overlap with either lysosomal or Golgi-specific dyes. Together, these results indicated that the two new Sf9 genes identified in this study encode broad-spectrum beta-N-acetylglucosaminidases that appear to have unusual intracellular distributions. Their relative lack of substrate specificity and acidic pH optima are consistent with a functional role for these enzymes in glycoprotein glycan and chitin degradation, but not with a role in N-glycoprotein glycan processing.
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29
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Mencarelli S, Cavalieri C, Magini A, Tancini B, Basso L, Lemansky P, Hasilik A, Li YT, Chigorno V, Orlacchio A, Emiliani C, Sonnino S. Identification of plasma membrane associated mature β-hexosaminidase A, active towards GM2 ganglioside, in human fibroblasts. FEBS Lett 2005; 579:5501-6. [PMID: 16212960 DOI: 10.1016/j.febslet.2005.08.081] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Revised: 08/31/2005] [Accepted: 08/31/2005] [Indexed: 11/24/2022]
Abstract
Mature beta-hexosaminidase A has been found associated to the external leaflet of plasma membrane of cultured fibroblasts. The plasma membrane association of beta-hexosaminidase A has been directly determined by cell surface biotinylation followed by affinity chromatography purification of the biotinylated proteins, and by immunocytochemistry. The immunological and biochemical characterization of biotinylated beta-hexosaminidase A revealed that the plasma membrane associated enzyme is fully processed, suggesting its lysosomal origin.
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Affiliation(s)
- Simona Mencarelli
- Department of Medicina Sperimentale e Scienze Biochimiche, University of Perugia, Italy
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Abstract
Fertilization is the union of a single sperm and an egg, an event that results in a diploid embryo. Animals use many mechanisms to achieve this ratio; the most prevalent involves physically blocking the fusion of subsequent sperm. Selective pressures to maintain monospermy have resulted in an elaboration of diverse egg and sperm structures. The processes employed for monospermy are as diverse as the animals that result from this process. Yet, the fundamental molecular requirements for successful monospermic fertilization are similar, implying that animals may have a common ancestral block to polyspermy. Here, we explore this hypothesis, reviewing biochemical, molecular, and genetic discoveries that lend support to a common ancestral mechanism. We also consider the evolution of alternative or radical techniques, including physiological polyspermy, with respect to our ability to describe a parsimonious guide to fertilization.
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Affiliation(s)
- Julian L Wong
- Department of Molecular Biology, Cellular Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
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31
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Harris HL, Braig HR. Sperm chromatin remodelling and Wolbachia-induced cytoplasmic incompatibility in Drosophila. Biochem Cell Biol 2003; 81:229-40. [PMID: 12897857 DOI: 10.1139/o03-053] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Wolbachia pipientis is an obligate bacterial endosymbiont, which has successfully invaded approximately 20% of all insect species by manipulating their normal developmental patterns. Wolbachia-induced phenotypes include parthenogenesis, male killing, and, most notably, cytoplasmic incompatibility. In the future these phenotypes might be useful in controlling or modifying insect populations but this will depend on our understanding of the basic molecular processes underlying insect fertilization and development. Wolbachia-infected Drosophila simulans express high levels of cytoplasmic incompatibility in which the sperm nucleus is modified and does not form a normal male pronucleus when fertilizing eggs from uninfected females. The sperm modification is somehow rescued in eggs infected with the same strain of Wolbachia. Thus, D. simulans has become an excellent model organism for investigating the manner in which endosymbionts can alter reproductive programs in insect hosts. This paper reviews the current knowledge of Drosophila early development and particularly sperm function. Developmental mutations in Drosophila that are known to affect sperm function will also be discussed.incompatibility.
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Affiliation(s)
- Harriet L Harris
- School of Biological Sciences, University of Wales, Bangor, Gwyneed, United Kingdom.
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