Abstract
We have studied by in situ hybridization the expression of the genes encoding the somatic form and the oocyte form of Xenopus laevis eEF-1 alpha. The somatic form of eEF-1 alpha (eEF-1 alpha S) mRNA is virtually undetectable in male and female germ cells of the adult gonad but is very abundant in embryonic cells after the neurula stage. In contrast, another form of eEF-1 alpha (eEF-1 alpha O) mRNA is highly concentrated in oogonia and in previtellogenic oocytes but is undetectable in eggs and embryos. eEF-1 alpha O mRNA is also present in spermatogonia and spermatocytes of adult testis. The latter finding identifies eEF-1 alpha O mRNA as a germ cell-specific gene product. Although germ cells contain very little eEF-1 alpha S mRNA, several eEF-1 alpha S retropseudogenes exist in X. laevis chromosomes. These genes are thought to arise in germ cells from reverse transcription of mRNA and subsequent integration of the cDNA copies into chromosomal DNA. We suggest that eEF-1 alpha S pseudogenes are generated in primordial germ cells of the embryo before they differentiate into oogonia or spermatogonia.
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- Davies B., Feo S., Heard E., Fried M. A strategy to detect and isolate an intron-containing gene in the presence of multiple processed pseudogenes. Proc Natl Acad Sci U S A. 1989 Sep;86(17):6691–6695. doi: 10.1073/pnas.86.17.6691. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Djé M. K., Mazabraud A., Viel A., le Maire M., Denis H., Crawford E., Brown D. D. Three genes under different developmental control encode elongation factor 1-alpha in Xenopus laevis. Nucleic Acids Res. 1990 Jun 25;18(12):3489–3493. doi: 10.1093/nar/18.12.3489. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dumont J. N. Oogenesis in Xenopus laevis (Daudin). I. Stages of oocyte development in laboratory maintained animals. J Morphol. 1972 Feb;136(2):153–179. doi: 10.1002/jmor.1051360203. [DOI] [PubMed] [Google Scholar]
- Ford P. J., Southern E. M. Different sequences for 5S RNA in kidney cells and ovaries of Xenopus laevis. Nat New Biol. 1973 Jan 3;241(105):7–12. doi: 10.1038/newbio241007a0. [DOI] [PubMed] [Google Scholar]
- Freytag S. O., Bock H. G., Beaudet A. L., O'Brien W. E. Molecular structures of human argininosuccinate synthetase pseudogenes. Evolutionary and mechanistic implications. J Biol Chem. 1984 Mar 10;259(5):3160–3166. [PubMed] [Google Scholar]
- Hay B., Jan L. Y., Jan Y. N. A protein component of Drosophila polar granules is encoded by vasa and has extensive sequence similarity to ATP-dependent helicases. Cell. 1988 Nov 18;55(4):577–587. doi: 10.1016/0092-8674(88)90216-4. [DOI] [PubMed] [Google Scholar]
- Hollis G. F., Hieter P. A., McBride O. W., Swan D., Leder P. Processed genes: a dispersed human immunoglobulin gene bearing evidence of RNA-type processing. Nature. 1982 Mar 25;296(5855):321–325. doi: 10.1038/296321a0. [DOI] [PubMed] [Google Scholar]
- Hourdry J., Brulfert A., Gusse M., Schoevaert D., Taylor M. V., Mechali M. Localization of c-myc expression during oogenesis and embryonic development in Xenopus laevis. Development. 1988 Dec;104(4):631–641. doi: 10.1242/dev.104.4.631. [DOI] [PubMed] [Google Scholar]
- Kalt M. R., Gall J. G. Observations on early germ cell development and premeiotic ribosomal DNA amplification in Xenopus laevis. J Cell Biol. 1974 Aug;62(2):460–472. doi: 10.1083/jcb.62.2.460. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Krieg P. A., Melton D. A. Developmental regulation of a gastrula-specific gene injected into fertilized Xenopus eggs. EMBO J. 1985 Dec 16;4(13A):3463–3471. doi: 10.1002/j.1460-2075.1985.tb04105.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Krieg P. A., Varnum S. M., Wormington W. M., Melton D. A. The mRNA encoding elongation factor 1-alpha (EF-1 alpha) is a major transcript at the midblastula transition in Xenopus. Dev Biol. 1989 May;133(1):93–100. doi: 10.1016/0012-1606(89)90300-x. [DOI] [PubMed] [Google Scholar]
- Lasko P. F., Ashburner M. Posterior localization of vasa protein correlates with, but is not sufficient for, pole cell development. Genes Dev. 1990 Jun;4(6):905–921. doi: 10.1101/gad.4.6.905. [DOI] [PubMed] [Google Scholar]
- Lasko P. F., Ashburner M. The product of the Drosophila gene vasa is very similar to eukaryotic initiation factor-4A. Nature. 1988 Oct 13;335(6191):611–617. doi: 10.1038/335611a0. [DOI] [PubMed] [Google Scholar]
- Lemischka I., Sharp P. A. The sequences of an expressed rat alpha-tubulin gene and a pseudogene with an inserted repetitive element. Nature. 1982 Nov 25;300(5890):330–335. doi: 10.1038/300330a0. [DOI] [PubMed] [Google Scholar]
- Madsen H. O., Poulsen K., Dahl O., Clark B. F., Hjorth J. P. Retropseudogenes constitute the major part of the human elongation factor 1 alpha gene family. Nucleic Acids Res. 1990 Mar 25;18(6):1513–1516. doi: 10.1093/nar/18.6.1513. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moldave K. Eukaryotic protein synthesis. Annu Rev Biochem. 1985;54:1109–1149. doi: 10.1146/annurev.bi.54.070185.005333. [DOI] [PubMed] [Google Scholar]
- Nishioka Y., Leder A., Leder P. Unusual alpha-globin-like gene that has cleanly lost both globin intervening sequences. Proc Natl Acad Sci U S A. 1980 May;77(5):2806–2809. doi: 10.1073/pnas.77.5.2806. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pöting A., Danker K., Hartmann L., Köster M., Wedlich D., Knöchel W. Two different mRNAs coding for identical elongation factor 1 alpha (EF-1 alpha) polypeptides in Xenopus laevis embryos. Differentiation. 1990 Aug;44(2):103–110. doi: 10.1111/j.1432-0436.1990.tb00543.x. [DOI] [PubMed] [Google Scholar]
- Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stutz F., Gouilloud E., Clarkson S. G. Oocyte and somatic tyrosine tRNA genes in Xenopus laevis. Genes Dev. 1989 Aug;3(8):1190–1198. doi: 10.1101/gad.3.8.1190. [DOI] [PubMed] [Google Scholar]
- Tso J. Y., Sun X. H., Kao T. H., Reece K. S., Wu R. Isolation and characterization of rat and human glyceraldehyde-3-phosphate dehydrogenase cDNAs: genomic complexity and molecular evolution of the gene. Nucleic Acids Res. 1985 Apr 11;13(7):2485–2502. doi: 10.1093/nar/13.7.2485. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Uetsuki T., Naito A., Nagata S., Kaziro Y. Isolation and characterization of the human chromosomal gene for polypeptide chain elongation factor-1 alpha. J Biol Chem. 1989 Apr 5;264(10):5791–5798. [PubMed] [Google Scholar]
- Vanin E. F., Goldberg G. I., Tucker P. W., Smithies O. A mouse alpha-globin-related pseudogene lacking intervening sequences. Nature. 1980 Jul 17;286(5770):222–226. doi: 10.1038/286222a0. [DOI] [PubMed] [Google Scholar]
- Vanin E. F. Processed pseudogenes: characteristics and evolution. Annu Rev Genet. 1985;19:253–272. doi: 10.1146/annurev.ge.19.120185.001345. [DOI] [PubMed] [Google Scholar]
- Viel A., Armand M. J., Callen J. C., Gomez De Gracia A., Denis H., le Maire M. Elongation factor 1 alpha (EF-1 alpha) is concentrated in the Balbiani body and accumulates coordinately with the ribosomes during oogenesis of Xenopus laevis. Dev Biol. 1990 Oct;141(2):270–278. doi: 10.1016/0012-1606(90)90383-t. [DOI] [PubMed] [Google Scholar]
- Wegnez M., Monier R., Denis H. Sequence heterogeneity of 5 S RNA in Xenopus laevis. FEBS Lett. 1972 Sep 1;25(1):13–20. doi: 10.1016/0014-5793(72)80443-5. [DOI] [PubMed] [Google Scholar]
- Weiner A. M., Deininger P. L., Efstratiadis A. Nonviral retroposons: genes, pseudogenes, and transposable elements generated by the reverse flow of genetic information. Annu Rev Biochem. 1986;55:631–661. doi: 10.1146/annurev.bi.55.070186.003215. [DOI] [PubMed] [Google Scholar]
- Wormington W. M., Brown D. D. Onset of 5 S RNA gene regulation during Xenopus embryogenesis. Dev Biol. 1983 Sep;99(1):248–257. doi: 10.1016/0012-1606(83)90273-7. [DOI] [PubMed] [Google Scholar]