Developmental regulation and secretion of nematode-specific cysteine-glycine domain proteins in Trichinella spiralis.
The muscle larva of Trichinella spiralis is an intracellular parasite of mammalian skeletal muscle, encapsulating within a portion of the myofiber and resulting in muscle de-differentiation. Parasite-derived factors secreted or excreted by the muscle larva are thought to play a role in the formation of the host-parasite complex and in the induction of changes in the host cell. We screened a library enriched for T. spiralis-specific cDNAs and identified a clone encoding a protein with similarity to a predicted secreted or extracellular Caenorhabditis elegans protein. The region of similarity included a conserved cysteine-glycine (CCG) domain, which we have identified as being nematode-specific. This domain is present in the predicted T. spiralis protein, Ts-CCG-1, and in a second protein, Ts-CCG-2, which we identified from subsequent analysis. We showed that while the Ts-ccg-1 gene is constitutively expressed, Ts-ccg-2 gene expression is restricted to the muscle L1 larva. Both predicted proteins contain an N-terminal signal peptide and we subsequently confirmed by MALDI-TOF mass spectrometric analyses of excretory/secretory peptide spots excised from two-dimensional gels that Ts-CCG-2 is secreted.
Gare
Daniel
D
Department of Molecular and Cell Biology, Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, Scotland, UK.
Boyd
Jacqueline
J
Connolly
Bernadette
B
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000032:analysis / Q000302:isolation & purification; D018509:DNA, Helminth / Q000737:chemistry / Q000302:isolation & purification; D015180:Electrophoresis, Gel, Two-Dimensional; D018507:Gene Expression Regulation, Developmental; D017238:Genes, Helminth; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D021382:Protein Sorting Signals / Q000235:genetics; D020543:Proteome / Q000032:analysis; D018510:RNA, Helminth / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D016415:Sequence Alignment; D017385:Sequence Homology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014158:Transcription, Genetic; D017160:Trichinella spiralis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*
D018076:DNA, Complementary; D018509:DNA, Helminth; D015801:Helminth Proteins; D021382:Protein Sorting Signals; D020543:Proteome; D018510:RNA, Helminth; D012333:RNA, Messenger