Kim Jin Young, Adhya Mausumi, Cho Somi K, Choi Kwang Sik, Cho Moonjae
Department of Biochemistry, School of Medicine, Cheju National University, Jeju 690-756, Republic of Korea.
Fish Shellfish Immunol. 2008 Nov;25(5):598-603. doi: 10.1016/j.fsi.2008.07.015. Epub 2008 Aug 5.
A novel C-type lectin designated Manila clam lectin 3 (MCL3), with a molecular weight of 17.380kDa, was identified among haemocyte expressed sequence tags of Perkinsus olseni-infected Manila clams. MCL3 was expressed in Escherichia coli M15 cells and purified with a Ni-NTA His-binding resin matrix. MCL3 agglutinated rabbit erythrocytes in the presence of Ca(+2). MCL3-induced agglutination was partially inhibited by GalNAc, Man, lactose, and raffinose, whereas the polysaccharides bovine mucin type II and Candida mannan completely inhibited agglutination. MCL3 was expressed in the haemocytes of Manila clams 3 days after infection with P. olseni and 1 day after infection with Vibrio tapetis. Based on real-time PCR analysis, mRNA transcripts of MCL3 were present in the adductor, foot, gill, mantle, palp, and siphon of Perkinsus-infected Manila clams. Furthermore, MCL3 was detected in the foot, gill, mantle, gonad, digestive gland, gonad connective tissue, intestine, and stomach by immunohistochemical localization.
在受奥尔森派琴虫感染的菲律宾蛤仔血细胞表达序列标签中，鉴定出一种新型C型凝集素，命名为菲律宾蛤仔凝集素3（MCL3），分子量为17.380 kDa。MCL3在大肠杆菌M15细胞中表达，并用镍-亚氨基二乙酸（Ni-NTA）组氨酸结合树脂基质进行纯化。MCL3在Ca(+2)存在的情况下能凝集兔红细胞。GalNAc、甘露糖、乳糖和棉子糖可部分抑制MCL3诱导的凝集，而多糖II型牛粘蛋白和念珠菌甘露聚糖则完全抑制凝集。在感染奥尔森派琴虫3天后以及感染灿烂弧菌1天后的菲律宾蛤仔血细胞中表达MCL3。基于实时聚合酶链反应（PCR）分析，在受派琴虫感染的菲律宾蛤仔闭壳肌、足、鳃、外套膜、触须和虹管中存在MCL3 mRNA转录本。此外，通过免疫组织化学定位在足、鳃、外套膜、性腺、消化腺、性腺结缔组织、肠和胃中检测到MCL3。
