Novel mannose-specific lectins found in torafugu, Takifugu rubripes: A review |
| |
Authors: | Shigeyuki Tsutsui Masaki Okamoto Satoshi Tasumi Hiroaki Suetake Kiyoshi Kikuchi Yuzuru Suzuki |
| |
Institution: | Fisheries Laboratory, The University of Tokyo, Hamamatsu, Shizuoka 431-0214, Japan |
| |
Abstract: | In earlier work, we identified a novel mannose-specific lectin, termed pufflectin-s, from the skin mucus of torafugu, Takifugu rubripes. We here make a brief review on the lectin. The amino acid sequence of pufflectin-s shares sequence homology with mannose-binding lectins of monocotyledonous plants, and has conserved two of three carbohydrate recognition domains, QDNVY motifs, of these plant lectins. By site-directed mutagenesis, we verified that the QDNVY motif in the N-terminal region was critical to the mannose-binding function of pufflectin-s. RT-PCR and Northern blot analyses indicated that the pufflectin-s gene is expressed in the gill, oral cavity wall, esophagus, and skin. In addition, an isoform, pufflectin-i, which shares 91.4% amino acid identity with pufflectin-s, was isolated from the intestine. Using immunohistochemistry, pufflectin-s could be detected exclusively in the epithelial cells of the skin, gill, oral cavity wall and esophagus, whereas pufflectin-i was observed in both mucous and epithelial cells in the intestine. Nevertheless, mRNAs for both pufflectins were detected only in epithelial cells of these tissues with in situ hybridization. Pufflectin-s agglutinated some bacteria isolated from rearing water and from fish skin. This lectin also bound to a parasite, Heterobothrium okamotoi, suggesting that it may play an important role in the self-defense system of fugu. |
| |
Keywords: | Fish Skin mucus Lectin Fugu Takifugu rubripes Immune system Structural diversity Mucosal tissue Anti-bacterial and parasite activity |
本文献已被 ScienceDirect 等数据库收录! |
|