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Plant lectins are carbohydrate-binding proteins with nonimmune origin,which can reversibly bind with carbohydrates,agglutinate cells,and precipitate polysaccharides and glycoconjugates.Plant lectins have attracted much attention for their anti-virus,anti-proliferation,and pro-apoptosis properties.Thus the exploration of new lectins has received special attention.Here we purified a mannose-binding lectin from the rhizomes of Liparis nervosa by ion exchange chromatography on DEAE-Sepharose,affinity chromatography on Mannose-Sepharose 4B,and gel filtration chromatography on Sephacryl S-100.The purified L.nervosa lectin (LNL) was identified to be a monomeric protein with a molecular mass of 13 kDa.LNL exhibited hemagglutinating activity towards rabbit erythrocytes,and its activity could be strongly inhibited by D-mannose,N-acetyl glucosamine and thyroglobulin.In vitro experiments showed that LNL exhibited a comparable anti-fungal activity against Piricularia oryzae (Cavara),Bipolaris maydis,Fusarium graminearum,and Sclerotium rolfsii,and anti-proliferation activity against tumor cells by inducing apoptosis.The full-length cDNA sequence of LNL is 715 bp in length and contains a 525 bp open reading frame (ORF) encoding a 110-residue mature protein.It was predicted to have three mannose-binding conserved motifs 'QXDXNXVXY'.The binding pattern of LNL was further revealed by homology modeling and molecular docking.We demonstrated that LNL is not only a potential therapeutic candidate against tumor but also a new anti-fungal agent.