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Mol Cell Biol. Aug 1988; 8(8): 3008–3016.
PMCID: PMC363526

Small gene family encoding an eggshell (chorion) protein of the human parasite Schistosoma mansoni.

Abstract

We have isolated six independent genomic clones encoding schistosome chorion or eggshell proteins from a Schistosoma mansoni genomic library. A linkage may of five of the clones spanning 35 kilobase pair (kbp) of the S. mansoni genome was constructed. The region contained two eggshell protein genes closely linked, separated by 7.5 kbp of intergenic DNA. The two genes of the cluster were arranged in the same orientation, that is, they were transcribed from the same strand. The sixth clone probably represents a third copy of the eggshell gene that is not contained within the 35-kbp region. The 5' end of the mRNA transcribed from these genes was defined by primer extension directly off the RNA. The ATCAT cap site sequence was homologous to a silkmoth chorion PuTCATT cap site sequence, where Pu indicates any purine. DNA sequence analysis showed that there were no introns in these genes. The DNA sequences of the three genes were very homologous to each other and to a cDNA clone, pSMf61-46, differing only in three or four nucleotides. A multiple TATA box was located at positions -23 to -31, and a CAAAT sequence was located at -52 upstream of the eggshell transcription unit. Comparison of sequences in regions further upstream with silkmoth and Drosophila sequences revealed several very short elements that were shared. One such element, TCACGT, recently shown to be an essential cis-regulatory element for silkmoth chorion gene promoter function, was found at a similar position in all three organisms.

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Selected References

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  • Bobek L, Rekosh DM, van Keulen H, LoVerde PT. Characterization of a female-specific cDNA derived from a developmentally regulated mRNA in the human blood fluke Schistosoma mansoni. Proc Natl Acad Sci U S A. 1986 Aug;83(15):5544–5548. [PMC free article] [PubMed]
  • Byram JE, Senft AW. Structure of the schistosome eggshell: amino acid analysis and incorporation of labelled amino acids. Am J Trop Med Hyg. 1979 May;28(3):539–547. [PubMed]
  • Cordingley JS. Trematode eggshells: Novel protein biopolymers. Parasitol Today. 1987 Nov;3(11):341–344. [PubMed]
  • Duvall RH, DeWitt WB. An improved perfusion technique for recovering adult schistosomes from laboratory animals. Am J Trop Med Hyg. 1967 Jul;16(4):483–486. [PubMed]
  • Goldsmith MR, Kafatos FC. Developmentally regulated genes in silkmoths. Annu Rev Genet. 1984;18:443–487. [PubMed]
  • Johnson KS, Taylor DW, Cordingley JS. Possible eggshell protein gene from Schistosoma mansoni. Mol Biochem Parasitol. 1987 Jan 2;22(1):89–100. [PubMed]
  • Jones CW, Kafatos FC. Structure, organization and evolution of developmentally regulated chorion genes in a silkmoth. Cell. 1980 Dec;22(3):855–867. [PubMed]
  • Kunz W, Opatz K, Finken M, Symmons P. Sequences of two genomic fragments containing an identical coding region for a putative egg-shell precursor protein of Schistosoma mansoni. Nucleic Acids Res. 1987 Jul 24;15(14):5894–5894. [PMC free article] [PubMed]
  • Lecanidou R, Rodakis GC, Eickbush TH, Kafatos FC. Evolution of the silk moth chorion gene superfamily: gene families CA and CB. Proc Natl Acad Sci U S A. 1986 Sep;83(17):6514–6518. [PMC free article] [PubMed]
  • Levine J, Spradling A. DNA sequence of a 3.8 kilobase pair region controlling Drosophila chorion gene amplification. Chromosoma. 1985;92(2):136–142. [PubMed]
  • Mitsialis SA, Kafatos FC. Regulatory elements controlling chorion gene expression are conserved between flies and moths. Nature. 1985 Oct 3;317(6036):453–456. [PubMed]
  • Orr W, Komitopoulou K, Kafatos FC. Mutants suppressing in trans chorion gene amplification in Drosophila. Proc Natl Acad Sci U S A. 1984 Jun;81(12):3773–3777. [PMC free article] [PubMed]
  • Osheim YN, Miller OL., Jr Novel amplification and transcriptional activity of chorion genes in Drosophila melanogaster follicle cells. Cell. 1983 Jun;33(2):543–553. [PubMed]
  • Sanger F, Nicklen S, Coulson AR. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. [PMC free article] [PubMed]
  • Simpson AJ, Chaudri M, Knight M, Kelly C, Rumjanek F, Martin S, Smithers SR. Characterisation of the structure and expression of the gene encoding a major female specific polypeptide of Schistosoma mansoni. Mol Biochem Parasitol. 1987 Jan 15;22(2-3):169–176. [PubMed]
  • Spoerel N, Nguyen HT, Kafatos FC. Gene regulation and evolution in the chorion locus of Bombyx mori. Structural and developmental characterization of four eggshell genes and their flanking DNA regions. J Mol Biol. 1986 Jul 5;190(1):23–35. [PubMed]
  • Spradling AC, Mahowald AP. Amplification of genes for chorion proteins during oogenesis in Drosophila melanogaster. Proc Natl Acad Sci U S A. 1980 Feb;77(2):1096–1100. [PMC free article] [PubMed]
  • van Keulen H, Loverde PT, Bobek LA, Rekosh DM. Organization of the ribosomal RNA genes in Schistosoma mansoni. Mol Biochem Parasitol. 1985 May;15(2):215–230. [PubMed]
  • Wong YC, Pustell J, Spoerel N, Kafatos FC. Coding and potential regulatory sequences of a cluster of chorion genes in Drosophila melanogaster. Chromosoma. 1985;92(2):124–135. [PubMed]

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