skip to main content

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

The authors isolated six independent genomic clones encoding schistosome chorion or eggshell proteins from a Schistosoma mansoni genomic library. A linkage map of five of the clones spanning 35 kilobase pairs (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 nucleotices. 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 ofmore » sequences in regions further upstream with silkmoth and Drosophila sequences revealed 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.« less
Authors:
; ;
Publication Date:
OSTI Identifier:
7040431
Resource Type:
Journal Article
Resource Relation:
Journal Name: Mol. Cell. Biol.; (United States); Journal Volume: 8:8
Research Org:
Departments of Microbiology, State Univ. of New York at Buffalo, Buffalo, NY (US)
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; DROSOPHILA; GENETIC MAPPING; SCHISTOSOMA; SILKWORM; DNA SEQUENCING; DNA-CLONING; PROTEINS; TRANSCRIPTION; ANIMALS; ARTHROPODS; CLONING; DIPTERA; FLIES; FRUIT FLIES; HELMINTHS; INSECTS; INVERTEBRATES; LEPIDOPTERA; MAPPING; MOTHS; ORGANIC COMPOUNDS; PLATYHELMINTHS; STRUCTURAL CHEMICAL ANALYSIS; TREMATODES 550200* -- Biochemistry; 550400 -- Genetics