Molecular cloning and characterization of a C-type lectin from the cotton bollworm, Helicoverpa armigera.
C-type lectins participate in pathogen recognition and other defense responses in innate immunity as well as in cell-cell interactions. A new cDNA encoding a 335-residue polypeptide containing two tandem C-type lectin domains was cloned from the haemocytes of Helicoverpa armigera (Ha-lectin). Northern hybridizations revealed that the mRNA of Ha-lectin was expressed constitutively in haemocytes, and was up-regulated following injections of bacteria, yeast, or virus. Ha-lectin expression was also induced in the fat body when larvae were injected with bacteria, yeast or 20-hydroxyecdysone and a non-steroidal ecdysone agonist, RH-2485. The Ha-lectin was detected in granular haemocytes. The recombinant protein (rHa-lectin) expressed in Escherichia coli had hemagglutinating and sugar-binding activities. The native Ha-lectin protein was identified in haemocytes and plasma using a polyclonal antiserum raised against rHa-lectin by immunoblotting techniques. All together, our results suggest that the Ha-lectin gene is involved in innate immunity, and may also participate in the molting process.
Chai
Lian-Qin
LQ
School of Life Sciences, Shandong University, Jinan 250100, Shandong, China.
Tian
Yuan-Yuan
YY
Yang
Dan-Tong
DT
Wang
Jin-Xing
JX
Zhao
Xiao-Fan
XF
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D004440:Ecdysone / Q000037:antagonists & inhibitors / Q000494:pharmacology; D004441:Ecdysterone / Q000494:pharmacology; D006434:Hemocytes / Q000378:metabolism*; D006834:Hydrazines / Q000494:pharmacology; D007605:Juvenile Hormones / Q000494:pharmacology; D007814:Larva / Q000378:metabolism; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009036:Moths / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*
D006834:Hydrazines; D007605:Juvenile Hormones; D037181:Lectins, C-Type; D004440:Ecdysone; D004441:Ecdysterone; C406712:methoxyfenozide