A role for Hemolectin in coagulation and immunity in Drosophila melanogaster.
Hemolectin has been identified as a candidate clotting factor in Drosophila. We reassessed the domain structure of Hemolectin (Hml) and propose that instead of C-type lectin domains, the two discoidin domains are most likely responsible for the protein's lectin activity. We also tested Hml's role in coagulation and immunity in Drosophila. Here we describe the isolation of a new hml allele in a forward screen for coagulation mutants, and our characterization of this and two other hml alleles, one of which is a functional null. While loss of Hml had strong effects on larval hemolymph coagulation ex vivo, mutant larvae survived wounding. Drosophila thus possesses redundant hemostatic mechanisms. We also found that loss of Hml in immune-handicapped adults rendered them more sensitive to Gram(-) bacterial infection. This demonstrates an immunological role of this clotting protein and reinforces the importance of the clot in insect immunity.
Lesch
Christine
C
Department of Molecular Biology and Functional Genomics, University of Stockholm, Svante Arrhenius väg 16-18, 10691 Stockholm, Sweden.
Goto
Akira
A
Lindgren
Malin
M
Bidla
Gawa
G
Dushay
Mitchell S
MS
Theopold
Ulrich
U
D000818:Animals; D001777:Blood Coagulation; D029721:Drosophila Proteins / Q000276:immunology* / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D017344:Genes, Insect; D006434:Hemocytes / Q000166:cytology / Q000378:metabolism; D006458:Hemolymph / Q000276:immunology / Q000502:physiology*; D006487:Hemostasis; D007814:Larva / Q000235:genetics / Q000276:immunology / Q000502:physiology; D037102:Lectins / Q000276:immunology* / Q000378:metabolism*
D029721:Drosophila Proteins; C476120:Hml protein, Drosophila; D037102:Lectins