Immulectin-4 from the tobacco hornworm Manduca sexta binds to lipopolysaccharide and lipoteichoic acid.
Insect C-type lectins function as pattern recognition receptors in innate immunity. In the tobacco hornworm Manduca sexta, we have previously isolated three C-type lectins named immulectins, which are involved in innate immune responses. Here, we report a new member of the immulectin family, immulectin-4 (IML-4). IML-4 mRNA was detected in the fat body of control larvae and was induced in the fat body when larvae were injected with bacteria. Recombinant IML-4 bound to bacterial lipopolysaccharide (LPS) and lipoteichoic acid (LTA), and the binding activity was not affected by addition of calcium or EGTA. IML-4 agglutinated bacteria and yeast, and agglutination of Escherichia coli by IML-4 was concentration- and calcium-dependent. IML-4 also enhanced haemocyte encapsulation and melanization.
Yu
X-Q
XQ
Division of Cell Biology and Biophysics, School of Biological Sciences, University of Missouri-Kansas City, 64110, USA. Yux@umkc.edu
Ling
E
E
Tracy
M E
ME
Zhu
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002118:Calcium / Q000502:physiology; D018076:DNA, Complementary; D004926:Escherichia coli / Q000378:metabolism; D015870:Gene Expression; D006434:Hemocytes / Q000276:immunology; D019476:Insect Proteins / Q000378:metabolism*; D037181:Lectins, C-Type / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000378:metabolism*; D018402:Manduca / Q000378:metabolism* / Q000382:microbiology; D008969:Molecular Sequence Data; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013211:Staphylococcus aureus / Q000378:metabolism; D013682:Teichoic Acids / Q000378:metabolism*
D018076:DNA, Complementary; D019476:Insect Proteins; D037181:Lectins, C-Type; D008070:Lipopolysaccharides; D013682:Teichoic Acids; C121403:immulectin, Manduca sexta; C009900:lipoteichoic acid; D002118:Calcium