1
|
Durante LDS, Hollmann G, Nazari EM. Impact of exposure to glyphosate-based herbicide on morphological and physiological parameters in embryonic and larval development of zebrafish. ENVIRONMENTAL TOXICOLOGY 2024; 39:1822-1835. [PMID: 38083805 DOI: 10.1002/tox.24024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 07/20/2023] [Accepted: 10/31/2023] [Indexed: 02/08/2024]
Abstract
Glyphosate-based herbicides (GBH) have been commonly used in agriculture to inhibit weed growth and increase yields. However, due to the high solubility of these herbicides in water, they can reach aquatic environments, by infiltration, erosion, and/or lixiviation, affecting non target organisms. Thus, this study aimed to characterize the toxicity of GBH Roundup WG® (RWG®) during the embryonic and larval development of Danio rerio. Embryos (3 hours post fertilization, hpf-until hatching) and larvae (3 days post fertilization, dpf to 6 dpf) were exposed to concentrations of 0.065 and 6.5 mg L-1 . They were evaluated for survival, hatching, spontaneous movements, heartbeat, morphology, and morphometry by in vivo photographs in microscope, cell proliferation and apoptosis by immunohistochemistry, and exploratory behavior and phototropism by video recording. Our results showed an increase in embryo and larvae mortality in those exposed to 0.065 mg L-1 , as well as a reduction in spontaneous embryo movements. The larval heartbeats showed a decrease at 4 dpf in the group exposed to 0.065 mg L-1 and an increase at 5 and 6 dpf in both exposed groups. Cell proliferation was reduced in both groups exposed in embryos and only in the 0.065 mg L-1 group in larvae, while cell death increased in embryos exposed to 6.5 mg L-1 . These results demonstrated the toxic effect of low concentrations of the herbicide RWG® during embryonic and larval development of non target organisms, as well as the importance of constantly reviewing acceptable limits for exposure in natural environments.
Collapse
Affiliation(s)
- Laíse da Silva Durante
- Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e do Desenvolvimento, Universidade Federal de Santa Catarina - UFSC, Florianópolis, Brazil
| | - Gabriela Hollmann
- Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e do Desenvolvimento, Universidade Federal de Santa Catarina - UFSC, Florianópolis, Brazil
| | - Evelise Maria Nazari
- Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e do Desenvolvimento, Universidade Federal de Santa Catarina - UFSC, Florianópolis, Brazil
| |
Collapse
|
2
|
Abstract
Cryopreservation has not been used successfully to preserve fish embryos, although chilling techniques have been used with good results. The aim of this study was to chill Piaractus brachypomus embryos at - 10°C for various storage times. Embryos at the following ontogenetic stages were used: blastoderm - 1.2 hours post-fertilization (hpf); epiboly - 5 hpf; blastopore closure - 8 hpf; and appearance of the optic vesicle - 13 hpf. One hundred embryos were selected from each ontogenetic stage and chilled at - 10°C for 6 or 10 h. The results were analysed using analysis of variance (ANOVA) and Tukey's test at a 5% significance level. A significantly greater number of completely developed live larvae were observed following embryonic treatment with a cryoprotectant solution that contained 17.5% sucrose and 10% methanol. There was no survival for embryos cooled at - 10°C in initial developmental stages (1, 2 and 5 h hpf). Furthermore, higher survival rates were observed when embryos were treated at more advanced developmental stages (8 and 13 hpf). Therefore, P. brachypomus embryos at the blastopore-closure (8 hpf) or appearance-of-optic-vesicle (13 hpf) stages should be used for embryo chilling protocols and chilling should be performed using a 17.5% sucrose with a 10% methanol solution at - 10°C for up to 6 h. The best results were obtained with 13-hpf and 8-hpf embryos and cooling at 6 h of storage.
Collapse
|
3
|
Muncaster S, Andersson E, Kjesbu OS, Taranger GL, Skiftesvik AB, Norberg B. The reproductive cycle of female Ballan wrasse Labrus bergylta in high latitude, temperate waters. JOURNAL OF FISH BIOLOGY 2010; 77:494-511. [PMID: 20701636 DOI: 10.1111/j.1095-8649.2010.02691.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This 2 year study examined the reproductive cycle of wild female Ballan wrasse Labrus bergylta in western Norway as a precursor to captive breeding trials. Light microscopy of ovarian histology was used to stage gonad maturity and enzyme-linked immuno-absorbent assay (ELISA) to measure plasma concentrations of the sex steroids testosterone (T) and 17beta-oestradiol (E(2)). Ovarian recrudescence began in late autumn to early winter with the growth of previtellogenic oocytes and the formation of cortical alveoli. Vitellogenic oocytes developed from January to June and ovaries containing postovulatory follicles (POF) were present between May and June. These POF occurred simultaneously among other late maturity stage oocytes. Plasma steroid concentration and organo-somatic indices increased over winter and spring. Maximal (mean +/-s.e.) values of plasma T (0.95 +/- 0.26 ng ml(-1)), E(2) (1.75 +/- 0.43 ng ml(-1)) and gonado-somatic index (I(G); 10.71 +/- 0.81) occurred in April and May and decreased greatly in July when only postspawned fish with atretic ovaries occurred. Evidence indicates that L. bergylta are group-synchronous multiple spawners with spawning occurring in spring and peaking in May. A short resting period may occur between late summer and autumn when previtellogenic oocytes predominate and steroid levels are minimal.
Collapse
Affiliation(s)
- S Muncaster
- Institute of Marine Research, P.O. Box 187, Nordnes, N-5817 Bergen, Norway.
| | | | | | | | | | | |
Collapse
|
4
|
Prisco M, Del Giudice G, Agnese M, Ricchiari L, Campanella C, Andreuccetti P. Organization of the vitelline envelope in ovarian follicles ofTorpedo marmorataRisso, 1810 (Elasmobranchii: Torpediniformes). JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2009; 312:714-21. [DOI: 10.1002/jez.b.21289] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
5
|
Xu Y, Lei Y, Liu Q, Liu Y, Liu S, Cheng H, Deng F. Cloning, characterization and expression ofzvep, a novel vitelline envelope-specific gene in the zebrafish ovary. Mol Reprod Dev 2009; 76:593-600. [DOI: 10.1002/mrd.20985] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
6
|
Maradonna F, Carnevali O. Vitellogenin, zona radiata protein, cathepsin D and heat shock protein 70 as biomarkers of exposure to xenobiotics. Biomarkers 2008; 12:240-55. [PMID: 17453739 DOI: 10.1080/13547500601070859] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The antagonistic and/or synergistic effects of different chemical compounds were examined in the marine teleost, Gobius niger, by testing a series of biomarkers involved in fish reproduction. Among the biomarkers analysed, vitellogenin (VTG) and zona radiata proteins (ZRP) are key molecules involved in reproduction, widely used to detect the presence of pollutants in the marine environment, while heat shock protein 70 (HSP70) and cathepsin D (CATD) have recently been introduced as bioindicators of endocrine disruption. The detection of VTG and ZRP in the plasma of wild male specimens is universally accepted as an early warning signal of environmental pollution. The evaluation of VTG, ZRP and CATD expression demonstrated the oestrogenic effect of nonylphenol on both male and female fish; on the contrary beta-naphthoflavone behaves mainly as an anti-oestrogen although, when co-injected with compounds with oestrogenic activity, it enhances ZRP gene expression. Regarding the chaperone, all treatments stressed the fish, inducing an increase in HSP70 gene transcription. The results obtained underlined the importance of testing the effects of compound mixtures: fish in the wild are subjected to a blend of chemicals and the effects observed derive from the synergic or antagonistic interactions of these compounds.
Collapse
Affiliation(s)
- F Maradonna
- Dipartimento di Scienze del Mare, Università Politecnica delle Marche, Via Brecce Bianche, Ancona, Italy
| | | |
Collapse
|
7
|
Quagio-Grassiotto I, Guimarães ACD. Follicular epithelium, theca and egg envelope formation in Serrasalmus spilopleura (Teleostei, Characiformes, Characidae). ACTA ZOOL-STOCKHOLM 2008. [DOI: 10.1046/j.1463-6395.2003.00137.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
8
|
Lee C, Na JG, Lee KC, Park K. Choriogenin mRNA induction in male medaka, Oryzias latipes as a biomarker of endocrine disruption. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2002; 61:233-241. [PMID: 12359393 DOI: 10.1016/s0166-445x(02)00060-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The fish egg envelope has been known to consist of two distinct layers. The outer layer is thin and is formed around the oocytes during the later stage of previtellogenic development. The inner layer, called zona radiata, is thicker than outer layer and occupies most of the egg envelope. Zona radiata proteins of medaka (Oryzias latipes) consist of two major subunit groups, ZI-1,2 and ZI-3. The precursors of ZI-1,2 and ZI-3 have been named choriogenin H and choriogenin L, respectively. They are synthesized in the liver in response to estrogen, and then released into the blood stream and incorporated into the zona radiata in sexually matured female medaka. However, choriogenin is also induced in male medaka when the fish are exposed to estrogenic chemicals. Choriogenin can be suggested as a possible biomarker of endocrine disruption in fish, however, relatively little has been known about chorogenin gene expression by estrogenic chemicals. In this study, full sequence of choriogenin L DNA was identified, and measurement of choriogenin mRNA induction was established in medaka by use of RT-PCR technique. Also estrogenic effects of industrial chemicals were evaluated by this tool. When mature male medaka was treated with bisphenol A, nonylphenol, and 17alpha-ethinylestradiol for 6 days, respectively, the expression levels of choriogenin L and H mRNA were elevated in treated groups. The induction of choriogenin subunits expression by these chemicals showed a dose-dependent pattern and choriogenin L was found to be more sensitive than choriogenin H.
Collapse
Affiliation(s)
- Chulwoo Lee
- Risk Research Department, National Institute of Environmental Research, Gyeongseo-dong, Seo-gu, Incheon 404-170, South Korea
| | | | | | | |
Collapse
|
9
|
Fujita T, Shimizu M, Hiramatsu N, Fukada H, Hara A. Purification of serum precursor proteins to vitelline envelope (choriogenins) in masu salmon, Oncorhynchus masou. Comp Biochem Physiol B Biochem Mol Biol 2002; 132:599-610. [PMID: 12091106 DOI: 10.1016/s1096-4959(02)00075-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Three vitelline envelope-related proteins (VERPs), very-high-molecular-weight VERP (vhVERP), high-molecular-weight VERP (hVERP) and low-molecular-weight VERP (lVERP) were purified from female masu salmon serum. The apparent molecular weights of vhVERP, hVERP and lVERP, in their native state, were 520, 88 and 54 kDa, respectively, by gel-filtration chromatography. Very-high-molecular-weight VERP comprises two subunits, corresponding to 175 and 126 kDa. On SDS-PAGE, hVERP and lVERP migrate at 53 and 47 kDa, respectively. Amino acid analysis of vhVERP and hVERP showed that they share a high content of glutamic acid and proline. By contrast, lVERP is rich in glutamic acid and asparatic acid. These features are in good agreement with the amino acid composition of the vitelline envelope. Immuno-biochemical analysis suggested that vhVERP is derived from hVERP by polymerization and/or aggregation. Antibodies against hVERP and lVERP specifically immunostained the vitelline envelope and liver of female masu salmon. In addition, both hVERP and lVERP were induced in the serum of estrogen-treated male fish. Taken together, it is suggested that hVERP and lVERP are homologous molecules with choriogenin H and choriogenin L in medaka, respectively. These results indicate that hVERP and lVERP are precursor proteins to the vitelline envelope (choriogenins) in masu salmon.
Collapse
Affiliation(s)
- Toshiaki Fujita
- Division of Marine Biosciences, Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido, 041-8611, Japan
| | | | | | | | | |
Collapse
|
10
|
Arukwe A, Kullman SW, Berg K, Goksøyr A, Hinton DE. Molecular cloning of rainbow trout (Oncorhynchus mykiss) eggshell zona radiata protein complementary DNA: mRNA expression in 17beta-estradiol- and nonylphenol-treated fish. Comp Biochem Physiol B Biochem Mol Biol 2002; 132:315-26. [PMID: 12031456 DOI: 10.1016/s1096-4959(02)00009-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A complementary DNA (cDNA) encoding the eggshell zona radiata protein (RBTZR: AF407574) has been cloned from the liver of estradiol-17beta (E(2))-treated rainbow trout (Oncorhynchus mykiss) by reverse-transcriptase polymerase chain reaction (RT-PCR). A set of degenerate primers homologous to the highly conserved cysteine-rich region of the zona radiata protein gene from salmon, winter flounder, medaka and carp were used for the initial RT-PCR. The resulting PCR product was cloned, sequenced and identified as the Zrp gene fragment based on amino acid sequence similarities. Based on the Zrp sequence from the initial PCR, a pair of gene-sequence primers was designed for 3'- and 5'- random amplification of cDNA ends (RACE). Cloning and sequencing of RACE products showed a 1349-bp Zrp gene encoding a 403-amino acid protein with a theoretical molecular mass of approximately 45 kDa. Alignment of the deduced amino acid sequence reveals that RbtZR is similar to piscine and mammalian zona pellucida proteins. The RbtZR gene, together with the estrogen receptor (ER) and vitellogenin (Vtg) genes, was further characterized and comparatively studied for transcriptional and translational expression in xenoestrogen- (nonylphenol, NP) and E(2)-treated juvenile rainbow trout in a time-course experiment. Northern and slot blot analysis showed that the RbtZR mRNA was expressed, in parallel with the ER and Vtg mRNA, in both NP- and E(2)-treated juvenile rainbow trout. Indirect enzyme-linked immunosorbent assay (ELISA) using monoclonal antibody raised against Atlantic salmon Zrp indicated the translational expression of RbtZR protein in blood plasma samples from NP- and E(2)-treated juvenile trout. The differential time-dependent transcriptional and translational expression and use of Zrp, ER and Vtg as sensitive biomarkers in environmental monitoring of endocrine disrupters in fish is discussed.
Collapse
Affiliation(s)
- Augustine Arukwe
- Great Lakes Institute for Environmental Research, University of Windor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada.
| | | | | | | | | |
Collapse
|
11
|
Larsson DGJ, Mayer I, Hyllner SJ, Förlin L. Seasonal variations of vitelline envelope proteins, vitellogenin, and sex steroids in male and female eelpout (Zoarces viviparus). Gen Comp Endocrinol 2002; 125:184-96. [PMID: 11884064 DOI: 10.1006/gcen.2001.7740] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The seasonal variations of vitelline envelope proteins, vitellogenin (VTG), and reproductive steroids were investigated in feral male and female eelpout, Zoarces viviparus. 17beta-Estradiol was present in both sexes with a peak in prespawning fish of 2.6 ng/ml in males and 2.7 ng/ml in females. 11-Ketotestosterone peaked in June at 4.2 and 0.47 ng/ml in males and females, respectively. A surge of testosterone was seen in both sexes in August, just prior to spawning. All steroid levels were low during early pregnancy. The vitelline envelope of the eelpout is composed of two major and one minor protein with molecular weights of 50, 55, and 44 kDa, respectively. An antiserum raised against solubilized vitelline envelope from turbot (Scophthalmus maximus) cross-reacted strongly with the 50-kDa protein from the isolated vitelline envelope and a similar-sized protein in female plasma and plasma from estrogenized males. Interestingly, the 50-kDa protein was also present at low levels in males as demonstrated by ELISA and Western blotting. In males, the 50-kDa protein did not follow the seasonal changes in 17beta-estradiol, but instead showed an almost perfect negative correlation with water temperature. VTG was present in female plasma as shown by Western blotting, but VTG was not detectable in male plasma despite relatively high endogenous estrogen levels. This suggests that the VTG induction by estradiol may be modulated by other factors in the eelpout.
Collapse
Affiliation(s)
- D G Joakim Larsson
- Department of Physiology/Endocrinology, Göteborg University, Göteberg, S-405 30, Sweden.
| | | | | | | |
Collapse
|
12
|
Vaccaro MC, Santo MG, Caputo M, Just M, Tian JD, Gong H, Lennarz WJ, Campanella C. Primary structure and developmental expression of Dp ZP2, a vitelline envelope glycoprotein homolog of mouse ZP2, in Discoglossus pictus, one of the oldest living Anuran species. Mol Reprod Dev 2001; 59:133-43. [PMID: 11389548 DOI: 10.1002/mrd.1016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A glycoprotein of the Xenopus vitelline envelope, gp 69/64, which mediates sperm binding, is closely related to the components of ZPA family, such as the mouse zona pellucida ZP2. To test the generality of these findings, we studied Discoglossus pictus, a species evolutionary distant from Xenopus and identified as a protein of 63 kDa in the vitelline envelope. Preliminary studies suggest that this protein may bind sperm at fertilization. We found that the 63-kDa protein is glycosylated and contains both N- and O-linked chains. We have cloned the cDNA encoding the Discoglossus protein of 63 kDa (Dp ZP2) by screening a Discoglossus cDNA library using Xenopus gp 69/64 cDNA as a probe. Analysis of the deduced sequence of Discoglossus protein revealed 48% identity with Xenopus gp 69/64 and 37-40% identity with mouse ZP2. The sequence conservation included a ZP domain, a potential furin cleavage site and a putative transmembrane domain. The N-terminus region of Dp ZP2 was 40% identical to the corresponding region of Xenopus gp 69/64 which has been shown to be essential for sperm binding to the VE. Although, as of yet, there is no evidence for sperm binding at the Dp ZP2 N-terminus, it is interesting that in this region three potential O-glycosylation sites are conserved in both species, in contrast to N-glycosylation sites. It was found that the Dp ZP2 mRNA is expressed in stage 1 oocytes and in the follicle cells surrounding the oocyte. Similarly, in Xenopus oocytes, the gp 69/64m RNA, was found in the oocytes, as well as in the somatic cells. Mol. Reprod. Dev. 59:133-143, 2001.
Collapse
Affiliation(s)
- M C Vaccaro
- Dipartimento di Biologia Evolutiva e Comparata, Napoli, Italy
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Westerlund L, Hyllner SJ, Schopen A, Olsson PE. Expression of three vitelline envelope protein genes in arctic char. Gen Comp Endocrinol 2001; 122:78-87. [PMID: 11352556 DOI: 10.1006/gcen.2001.7614] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Several studies have shown effects of estrogenic substances on endocrine and reproductive systems in wildlife. Measurement of plasma vitellogenin (VTG) is a commonly used method to determine exposure to estrogenic substances in fish. There is, however, a growing need for additional sensitive and accurate methods to detect estrogenic substances in vivo. The vitelline envelope proteins (VEPs) have been suggested, in other studies, as suitable biomarkers for estrogenic substances. The present study investigates the induction of VEPs in juvenile Arctic char (Salvelinus alpinus). The results demonstrate that VEP mRNA exhibits earlier induction than estrogen receptor mRNA or VTG mRNA following injection of juvenile Arctic char with a single dose of 17beta-estradiol (E2; 10 mg/kg bw). These results indicate that the VEPs have a higher sensitivity for E2 than VTG. However, an early and sex-independent expression of VEPbeta in estrogen-unchallenged juvenile Arctic char was observed. These findings suggests that the regulatory mechanisms of VEPs might be more complex than previously thought, which in turn may have implications for the usage of VEPs as biomarkers for xenoestrogen exposure.
Collapse
Affiliation(s)
- L Westerlund
- Department of Cell and Molecular Biology, Umeå University, Umeå, SE-901 87, Sweden
| | | | | | | |
Collapse
|
14
|
da Cruz-Landim C, Cruz-Höfling MA. Ultrastructure of ovarian follicular epithelium of the Amazonian fish Pseudotylosurus microps (Teleostei: Belonidae): morphological and histochemical characterization of the intercellular deposits. BRAZ J BIOL 2001; 61:133-40. [PMID: 11340471 DOI: 10.1590/s0034-71082001000100017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present paper reports the presence of great quantities of electrondense intercellular material in the follicular epithelium of P. microps. The material apparently is uptaken from circulation and enter the follicle through the intercellular spaces accumulating in the epithelial median-apical intercellular spaces and in perioocytic space. The accumulation starts in the early growth of the primary oocyte and proceed until vitellogenesis. The possible chemical nature and function of the deposits are discussed.
Collapse
Affiliation(s)
- C da Cruz-Landim
- Departamento de Biologia, Instituto de Biociências, Universidade Estadual Paulista, C.P. 199, CEP 13506-900, Rio Claro, SP, Brazil.
| | | |
Collapse
|
15
|
Watanabe S, Hara M, Watanabe Y. Male Internal Fertilization and Introsperm-like Sperm of the Seaweed Pipefish (Syngnathus schlegeli). Zoolog Sci 2000. [DOI: 10.2108/zsj.17.759] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
16
|
Wang H, Gong Z. Characterization of two zebrafish cDNA clones encoding egg envelope proteins ZP2 and ZP3. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1446:156-60. [PMID: 10395930 DOI: 10.1016/s0167-4781(99)00066-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Two zebrafish cDNA clones encoding homologs of mammalian zona pellucida proteins ZP2 and ZP3 were isolated from a whole adult cDNA library. The ZP2 clone encodes a protein of 428 amino acids. Unlike other teleost ZP2s that contain an N-terminal repetitive domain enriched with prolines and glutamines, the zebrafish ZP2 has no such repetitive domain. In the C-terminal non-repetitive domain, the zebrafish ZP2 shares 55-76% sequence identity with other teleost ZP2s. The ZP3 cDNA clone encodes a protein of 431 amino acids, which shares 61% sequence identity with a carp ZP3. Similar to mammalian ZP proteins, both zebrafish ZP2 and ZP3 contain several potential phosphorylation sites. However, unlike mammalian ZP proteins, both zebrafish ZP proteins contain almost no glycosylation site, which has been proposed to be important for interaction with sperm; thus, the ZP proteins may behave differently in mammals and teleosts. Northern blot analysis indicated that both zebrafish ZP2 and ZP3 mRNAs were expressed exclusively in the ovary and hence the ovary is likely the only site for ZP2 and ZP3 biosynthesis.
Collapse
Affiliation(s)
- H Wang
- Department of Biological Sciences, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore
| | | |
Collapse
|
17
|
Scapigliati G, Meloni S, Mazzini M. A monoclonal antibody against chorion proteins of the sea bass Dicentrarchus labrax (Linnaeus, 1758): studies of chorion precursors and applicability in immunoassays. Biol Reprod 1999; 60:783-9. [PMID: 10084949 DOI: 10.1095/biolreprod60.4.783] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The monoclonal antibody DLE7 was obtained against 44- to 50-kDa polypeptides solubilized from the vitelline envelope of the Mediterranean sea bass Dicentrarchus labrax. In Western blot analysis of chorion lysates it recognized cross-reactive bands at 44 kDa, 48 kDa, and 110 kDa. Previous affinity blotting with concanavalin-A showed that most of solubilized bands were glycosylated. Enzymatic deglycosylation of chorion proteins followed by Western blot analysis with DLE7 showed that the 48-kDa and 110-kDa antigens were differentially affected by endoglycosidase-F treatment. When DLE7 was employed in immunofluorescence analysis, isolated chorions and ovarian cryosections stained intensely. Positivity was also observed in liver cryosections of spawning females but not in liver of males and nonspawning females. To study the origin and delivery of chorion proteins, DLE7 was used in Western blot analysis of liver homogenates and blood serum of spawning females. Cross-reacting bands were detected in liver (90 kDa) and serum (180 kDa, 50 kDa). DLE7 was also used for the first time to set up an indirect ELISA assay to detect egg antigens in the blood of egg-producing females, raising the possibility of using DLE7 as a female-specific marker of spawning for sea bass.
Collapse
Affiliation(s)
- G Scapigliati
- Dipartimento Scienze Ambientali, Università della Tuscia, I-01100 Viterbo, Italy.
| | | | | |
Collapse
|
18
|
Oda S, Igarashi Y, Manaka K, Koibuchi N, Sakai-Sawada M, Sakai K, Morisawa M, Ohtake H, Shimizu N. Sperm-activating proteins obtained from the herring eggs are homologous to trypsin inhibitors and synthesized in follicle cells. Dev Biol 1998; 204:55-63. [PMID: 9851842 DOI: 10.1006/dbio.1998.9056] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of sperm motility by the egg is an ubiquitous phenomenon in the animal kingdom, but the molecules by which the egg activates sperm motility have been clarified in only a few invertebrate species. In the Pacific herring, Clupea pallasii, mature unfertilized eggs release the sperm-activating proteins which are prerequisite to successful fertilization. Complementary DNA clones encoding herring sperm-activating proteins were isolated from a herring ovarian complementary DNA library and amino acid sequences were deduced. The herring sperm-activating protein(s) is a secretory product(s) with a strong homology to Kazal-type trypsin inhibitors, such as mammalian acrosin inhibitors. The sperm-activating proteins were globally distributed in the outermost layer of the egg chorion and its gene was found to be expressed in the follicle cells which surround developing oocytes. These results suggest that in the Pacific herring, trypsin inhibitor-like proteins are synthesized in the follicle cells, secreted, accumulated in the egg chorion during oocyte development, and released into the milieu at spawning to activate the motility of spermatozoa at the time of gamete interaction.
Collapse
Affiliation(s)
- S Oda
- School of Science, University of Tokyo, Kanagawa, Miura, 238-0225, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Sugiyama H, Yasumasu S, Murata K, Iuchi I, Yamagami K. The third egg envelope subunit in fish: cDNA cloning and analysis, and gene expression. Dev Growth Differ 1998; 40:35-45. [PMID: 9563909 DOI: 10.1046/j.1440-169x.1998.t01-5-00005.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The inner layer of the egg envelope of a teleost fish, the medaka, Oryzias latipes, consists of two major subunit groups, ZI-1,2 and ZI-3. On SDS-PAGE, the ZI-1,2 group presents three glycoprotein bands that were considered to be composed of a common polypeptide moiety derived from their precursor, choriogenin H (Chg H). ZI-3 is a single glycoprotein derived from the precursor, choriogenin L (Chg L). In the present study, a fraction of a novel subunit protein was found in the V8 protease digest of ZI-1.2 that was partially purified from oocyte envelopes. This protein fraction was not present in the purified precursor, Chg H. By RT-PCR employing the primers based on the amino acid sequence of this fraction, a cDNA for the novel subunit was amplified, and a full-length clone of the cDNA was obtained by screening a cDNA library constructed from the spawning female liver. The clone consisted of 2025 b.p. and contained an open reading frame encoding the novel protein of 634 amino acids. This protein included Pro-X-Y repeat sequences in two-fifths of the whole length from its N-terminus. Northern blot analysis revealed that the gene expression for this protein occurred in the liver but not in the ovary of spawning female fish. This protein is considered as the third major subunit of the inner layer of the egg envelope of medaka.
Collapse
Affiliation(s)
- H Sugiyama
- Life Science Institute, Sophia University, Tokyo, Japan
| | | | | | | | | |
Collapse
|
20
|
Del Giacco L, Vanoni C, Bonsignorio D, Duga S, Mosconi G, Santucci A, Cotelli F. Identification and spatial distribution of the mRNA encoding the gp49 component of the gilthead sea bream, Sparus aurata, egg envelope. Mol Reprod Dev 1998; 49:58-69. [PMID: 9406196 DOI: 10.1002/(sici)1098-2795(199801)49:1<58::aid-mrd7>3.0.co;2-n] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A cDNA encoding the precursor of one of the major components of gilthead sea bream, Sparus aurata, egg envelope has been cloned by reverse transcriptase polymerase chain reaction (RT-PCR) techniques. The clone was isolated starting from total RNA extracted from the liver of spawning female fish and estradiol-17 beta-treated male fish. Sequence analysis revealed that the cDNA encoded a protein of 405 aa corresponding to 49-kDa component (termed gp49), a glycoprotein belonging to the N-linked type. The gp49 protein is homologous to the Zl-3 of medaka Oryzias latipes, the mammalian ZPC and ZPC homologues of Xenopus laevis (xlZPC) and carp Cyprinus carpio (ccZPC). In addition, the open reading frame also encodes an additional aa sequence, the signal peptide, located in the N-terminal region of the protein. RT-PCR and in situ expression analyses evidenced an organ-restricted pattern: the mRNA was detected only in liver of spawning female and estradiol-17 beta-treated male fish but not in other tissues.
Collapse
Affiliation(s)
- L Del Giacco
- Dipartimento di Biologia, Università di Milano, Italy
| | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
The cDNAs encoding carp ZP2 homologous to winter flounder and mammalian ZP2 were cloned. Carp ZP2 contains a tandemly repetitive domain and a nonrepetitive domain. A repeat is composed of 13 amino-acid residues whose consensus sequence is QQTSQQFQPQKPA/V. The length of the repetitive domain is highly variable, but that of the nonrepetitive domain is fairly constant among various cDNAs. The termination codons of various cDNAs appear at three different positions. Three groups of cDNAs were therefore categorized. Groups I-III encode a nonrepetitive domain of 356, 255, and 10 residues, respectively. A carp ZP2 gene corresponding to group II cDNA was cloned. It spans 2.4 kb and consists of eight exons and seven introns. Carp ZP2 mRNA was detected only in oocytes but not in other tissues. Carp ZP2 is heterogenous in size. The molecular weight ranges from 40-80 kDa. It is present in vitellogenic but not in previtellogenic oocytes, nor in other tissues. Carp ZP2 content in oocytes increases as vitellogenesis proceeds.
Collapse
Affiliation(s)
- Y S Chang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | | | | | | | | |
Collapse
|
22
|
Abstract
Two types of cDNAs coding for a major component of carp egg membrane were clones from a carp ovarian cDNA library. They encode polypeptides of 422-424 amino acid residues whose sequences are homologous to those of medaka and mammalian ZP3. Similar to the mammalian ZP3 genes, carp ZP3 gene also consists of eight exons and seven introns. Carp ZP3 genes are 2.9 kb in length and present in multiple forms. Carp ZP3 is a glycoprotein of 45 kDa. It was transcribed and translated exclusively in oocytes, in contrast with medaka ZP3, which was synthesized in liver. The transcription of carp ZP3 starts very early in oogenesis, but translation occurs during vitellogenesis, as it is present in vitellogenic but not in previtellogenic oocytes. ZP3 content in oocytes increases as vitellogenesis proceeds.
Collapse
Affiliation(s)
- Y S Chang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | | | | | | |
Collapse
|
23
|
Sugiyama H, Murata K, Iuchi I, Yamagami K. Evaluation of solubilizing methods of the egg envelope of the fish, Oryzias latipes, and partial determination of amino acid sequence of its subunit protein, ZI-3. Comp Biochem Physiol B Biochem Mol Biol 1996; 114:27-33. [PMID: 8759297 DOI: 10.1016/0305-0491(95)02111-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The inner layer of most teleostean egg envelopes, especially those after hardening, is almost insoluble in ordinary solvent, and therefore the inner layer of only the unhardened egg envelope has been subjected to solubilization with some potent solvents. We comparatively evaluated the methods of solubilization of the inner layer of egg envelope of medaka, Oryzias latipes, with SDS, urea and guanidium chloride (GuHCI). Analysis of the solubilized samples by SDS-polyacrylamide gel electrophoresis, comparison of their amino acid compositions or peptide maps using high-performance liquid chromatography and partial determination of their amino acid sequences showed that SDS and GuHCI were appropriate for solubilization and characterization of the envelope. Urea solubilization resulted in some artificial modifications of lysine and/or cysteine residues of envelope proteins. Partial determination of amino acid sequence of a subunit, ZI-3, isolated from the SDS-or GuHCI-solubilized envelope strongly suggested the identity of the envelope subunit, ZI-3, and its precursor, L-SF.
Collapse
Affiliation(s)
- H Sugiyama
- Life Science Institute, Sophia University, Tokyo, Japan
| | | | | | | |
Collapse
|
24
|
Bonsignorio D, Perego L, Del Giacco L, Cotelli F. Structure and macromolecular composition of the zebrafish egg chorion. ZYGOTE 1996; 4:101-8. [PMID: 8913023 DOI: 10.1017/s0967199400002975] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The chorion is the acellular envelope surrounding mature eggs of teleostean fish. The macromolecular composition of the zebrafish (Danio rerio) egg chorion, organised as a three-layered structure, has been analysed. SDS-PAGE analysis, under reducing conditions, of isolated and purified chorions revealed a reproducible pattern of four major polypeptides (116, 97, 50 and 43 kDa) and several minor bands. Lectin binding assays showed that both the 116 kDa and 50 kDa proteins were recognised by concanavalin agglutinin (Con A), Galanthus nivalis agglutinin (GNA), Sambucus nigra bark agglutinin (SNA) and Ricinus communis agglutinin (RCA 120), suggesting that these polypeptides are N-linked glycoproteins. By contrast, neither the 97 kDa nor the 43 kDa polypeptides were stained by these lectins, indicating that these polypeptides are not glycosylated. Amino acid analysis also showed significant differences in the average content of some amino acids, for example serine and proline, when compared with previous reports.
Collapse
|
25
|
Iwamatsu T, Shibata Y, Kanie T. Changes in chorion proteins induced by the exudate released from the egg cortex at the time of fertilization in the teleost, Oryzias latipes. Dev Growth Differ 1995. [DOI: 10.1046/j.1440-169x.1995.t01-4-00012.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
26
|
Characterization of yolk proteins during oocyte development of tilapia, Oreochromis mossambicus. Comp Biochem Physiol B Biochem Mol Biol 1995. [DOI: 10.1016/0305-0491(95)00068-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
27
|
Scapigliati G, Fausto AM, Zega S, Mazzini M. Characterization of the main egg chorion proteins of the whitefish Coregonus lavaretus L. (Osteichthyes, Salmonidae). Comp Biochem Physiol B Biochem Mol Biol 1995. [DOI: 10.1016/0305-0491(95)00043-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
28
|
Hyllner SJ, Fernàndez-Palacios Barber H, Larsson DG, Haux C. Amino acid composition and endocrine control of vitelline envelope proteins in European sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata). Mol Reprod Dev 1995; 41:339-47. [PMID: 8588933 DOI: 10.1002/mrd.1080410309] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The vitelline envelopes of European sea bass and gilthead sea bream are both composed of mainly four proteins with the molecular masses of 90, 52, 48, 45 kDa and 75, 50, 48, 44 kDa, respectively. Each protein has an amino acid composition that is characterized by a high content of proline and glutamic acid and a low content of cysteine, similar to the whole vitelline envelope of both species. The amino acid composition suggests that each protein is distinct but related to the other vitelline envelope proteins. The use of homologous antisera shows that both species have vitelline envelope proteins that are induced by estradiol-17 beta. As males of both species synthesize these proteins after treatment with estradiol-17 beta, the origin is not restricted to the ovaries. Vitellogenin of both European sea bass and gilthead sea bream has the apparent molecular mass of 170 kDa.
Collapse
Affiliation(s)
- S J Hyllner
- Department of Zoophysiology, University of Göteborg, Sweden
| | | | | | | |
Collapse
|
29
|
Hyllner SJ, Silversand C, Haux C. Formation of the vitelline envelope precedes the active uptake of vitellogenin during oocyte development in the rainbow trout, Oncorhynchus mykiss. Mol Reprod Dev 1994; 39:166-75. [PMID: 7826618 DOI: 10.1002/mrd.1080390208] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In order to study the initial formation of the vitelline envelope and the appearance of vitellogenin in oocytes of rainbow trout, females were sampled monthly from 19 to 5 mo before ovulation. Immunohistochemistry revealed that the formation of the vitelline envelope starts when the oocytes reach a diameter of about 450 microns. Oocytes of this size were first found in females sampled a year before ovulation at the time when plasma levels of estradiol-17 beta increased from 0.2 to 0.6 ng/ml. An antiserum directed against vitellogenin crossreacted with small vesicles (around 2 microns) present just inside the oolemma, when the oocytes reached a diameter of 600 microns. This was interpreted as an active uptake of vitellogenin. Oocytes of this size were first found in females sampled 9 mo before ovulation at the time when estradiol-17 beta levels increased from 0.6 to 1.0 ng/ml and the gonadal somatic index was doubled. Oocytes with a diameter of 600 microns had an immunoreactive vitelline envelope with a thickness of about 3 microns. It is apparent that the initial formation of the vitelline envelope starts before the active uptake of vitellogenin and that the low previtellogenic plasma levels of estradiol-17 beta observed in females are of physiological significance.
Collapse
Affiliation(s)
- S J Hyllner
- Department of Zoophysiology, University of Göteborg, Sweden
| | | | | |
Collapse
|
30
|
Oppen-Berntsen DO, Olsen SO, Rong CJ, Taranger GL, Swanson P, Walther BT. Plasma levels of eggshell zr-proteins, estradiol-17β, and gonadotropins during an annual reproductive cycle of Atlantic salmon (Salmo salar). ACTA ACUST UNITED AC 1994. [DOI: 10.1002/jez.1402680108] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
31
|
Lyons C, Payette K, Price J, Huang R. Expression and structural analysis of a teleost homolog of a mammalian zona pellucida gene. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(19)36930-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
32
|
Yamagami K, Hamazaki TS, Yasumasu S, Masuda K, Iuchi I. Molecular and cellular basis of formation, hardening, and breakdown of the egg envelope in fish. INTERNATIONAL REVIEW OF CYTOLOGY 1992; 136:51-92. [PMID: 1506146 DOI: 10.1016/s0074-7696(08)62050-1] [Citation(s) in RCA: 111] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- K Yamagami
- Life Science Institute, Sophia University, Tokyo, Japan
| | | | | | | | | |
Collapse
|
33
|
Murata K, Hamazaki TS, Iuchi I, Yamagami K. Spawning Female-Specific Egg Envelope Glycoprotein-Like Substances in Oryzias latipes. (egg envelope/spawning female fish/oogenesis/oocyte growth/Oryzias latipes). Dev Growth Differ 1991. [DOI: 10.1111/j.1440-169x.1991.00553.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
34
|
|
35
|
luchi I, Masuda K, Yamagami K. Change in Component Proteins of the Egg Envelope (Chorion) of Rainbow Trout during Hardening. (Fish Egg Envelope/Chorion/Chorion Proteins/Chorion Hardening/Egg Activation). Dev Growth Differ 1991. [DOI: 10.1111/j.1440-169x.1991.00085.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
36
|
Brivio MF, Bassi R, Cotelli F. Identification and characterization of the major components of the Oncorhynchus mykiss egg chorion. Mol Reprod Dev 1991; 28:85-93. [PMID: 1847292 DOI: 10.1002/mrd.1080280114] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The extracellular coat surrounding the fish egg, commonly called the chorion, is a primary envelope that confers biochemical and morphological identity typical of the species. Purified chorions can be easily isolated from either oocytes or ovulated eggs. The aim of this work was to analyze the macromolecular composition of the various chorion components in Oncorhynchus mykiss (Salmonids). SDS-PAGE analysis of purified chorion showed a reproducible pattern of four major components (129, 62, 54, and 47 kD), representing about 80% of total chorion proteins. The 129 and 47 kD polypeptides were periodic-acid Schiff (PAS) and concanavalin A positive. After chemical and enzymatic deglycosylation treatments only the 129 and 47 kD components proved to be glycosylated and to belong to the "asparagine-linked" glycoprotein family. Furthermore, peptide mapping performed on isolated polypeptides showed comigrating fragments on SDS-PAGE. These results suggest that the four main chorion polypeptides might share common structural features.
Collapse
Affiliation(s)
- M F Brivio
- Dipartimento di Biologia, Università degli Studi di Milano, Italy
| | | | | |
Collapse
|
37
|
Wallace RA, Selman K. Ultrastructural aspects of oogenesis and oocyte growth in fish and amphibians. JOURNAL OF ELECTRON MICROSCOPY TECHNIQUE 1990; 16:175-201. [PMID: 2243277 DOI: 10.1002/jemt.1060160302] [Citation(s) in RCA: 187] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Oogenesis, the early events of primary oocyte growth (meiotic arrest, synapsis, ribosomal gene duplication), and folliculogenesis can be seen to particular advantage in the germinal ridge of the syngnathan ovary. After budding off the germinal ridge (a compartment of the luminal epithelium), nascent follicles then enter into a linear array of developing follicles within which temporal and stage-specific events can be correlated with spatial distribution. Prominent features of the later phase of primary oocyte growth include intense transcriptional activity and the formation and subsequent dispersal of the Balbiani vitelline body (mitochondrial cloud) concomitant with an increase in cytoplasmic organelles and volume. Further oocyte growth is characterized by a period of cortical alveolus (in teleosts) or cortical granule (in anurans) formation, in which Golgi elements play a predominant role, and finally vitellogenesis. The latter process, which is responsible for the preponderance of oocyte growth, includes the hepatic synthesis and secretion of vitellogenin (VTG), the uptake of VTG from the bloodstream into the oocyte by receptor-mediated endocytosis, and the transport of VTG via endosomes and multivesicular bodies to forming yolk platelets. In the process, VTG is proteolytically cleaved into the yolk proteins, which assume either a monoclinic (in cyclostomes) or orthorhombic (in teleosts and amphibians) crystalline array. Other structures associated with the growing oocyte are also briefly discussed, including nuage, the vitelline envelope, intercellular junctions between the oocyte and overlying follicle cells, pigment, intramitochondrial crystals in ranidae, and annulate lamellae.
Collapse
Affiliation(s)
- R A Wallace
- Whitney Laboratory, University of Florida, St. Augustine 32086
| | | |
Collapse
|