A novel lectin with highly potent antiproliferative and HIV-1 reverse transcriptase inhibitory activities from cicada (Cicada flammata).
A dimeric lectin with a molecular weight of 60 kDa and high hemagglutinating activity was isolated from dried cicadas. It was adsorbed on Q-Sepharose and unadsorbed on Affi-Gel Blue gel. Its hemagglutinating activity was stable up to 55 degrees C and between pH 2 and 13. The activity was inhibited by glucuronic acid and raffinose, K(+) ions, and Mg(2+) ions. Cicada lectin potently inhibited proliferation of HepG2 hepatoma and MCF 7 breast cancer cells, with an IC(50) value of 0.76 and 0.49 microM, respectively. It potently inhibited HIV-1 reverse transcriptase activity with an IC(50) of 0.36 microM but was devoid of mitogenic activity on spleen cells. Its N-terminal sequence exhibited slight similarity to a conserved hypothetical protein from Culex quinquefasciatus and a gene product from transcript GH19834-RA of Drosophila grimshawi, but there was no resemblance to lectins from other insects, including Drosophila, Sarcophaga, Glossina, and Aedes species.
Ye
Xiu Juan
XJ
School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
Ng
Tzi Bun
TB
D000595:Amino Acid Sequence; D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification* / Q000494:pharmacology; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors*; D015497:HIV-1 / Q000187:drug effects* / Q000201:enzymology; D006386:Hemagglutination Tests; D006430:Hemiptera / Q000737:chemistry*; D006801:Humans; D019476:Insect Proteins / Q000302:isolation & purification* / Q000494:pharmacology*; D037102:Lectins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008934:Mitogens / Q000302:isolation & purification / Q000494:pharmacology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D018894:Reverse Transcriptase Inhibitors / Q000302:isolation & purification* / Q000494:pharmacology*; D017386:Sequence Homology, Amino Acid
D000970:Antineoplastic Agents; D019476:Insect Proteins; D037102:Lectins; D008934:Mitogens; D018894:Reverse Transcriptase Inhibitors; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase