Li Wenli, Terenius Olle, Hirai Makoto, Nilsson Anders S, Faye Ingrid
Department of Genetics, Microbiology and Toxicology, Stockholm University, Svante Arrheniuse v. 16E, SE-106 91 Stockholm, Sweden.
Dev Comp Immunol. 2005;29(10):853-64. doi: 10.1016/j.dci.2005.02.003. Epub 2005 Mar 22.
The Chinese oak silk moth Antheraea pernyi is an important silk producer. To understand microbial resistance of this moth, we cloned Hemolin, encoding a multifunctional immune protein belonging to the immunoglobulin superfamily, and examined the expression in gonads and fat body. The ApHemolin amino acid sequence was compared to other Hemolin sequences in order to predict functional sites. Several sites were conserved; among them a phosphate binding site, which according to 3D structure modelling does not appear in neuroglian, the phylogenetically closest related protein. In addition, two conserved KDG sequences in the C-C' loop of immunoglobulin domains 1 and 3, give rise to gamma-turns, which is a common motif in the C'-C'' loop of the hypervariable region L2 in vertebrate immunoglobulins. The comparisons also show variable regions of specific interest for future studies of hemolin and its interaction with microbial entities.
柞蚕是一种重要的产丝昆虫。为了解其对微生物的抗性，我们克隆了编码属于免疫球蛋白超家族的多功能免疫蛋白的血淋巴蛋白（Hemolin），并检测了其在性腺和脂肪体中的表达。将柞蚕血淋巴蛋白（ApHemolin）的氨基酸序列与其他血淋巴蛋白序列进行比较，以预测功能位点。发现了几个保守位点；其中一个磷酸结合位点，根据三维结构建模，在系统发育上最接近的相关蛋白神经胶质蛋白（neuroglian）中未出现。此外，免疫球蛋白结构域1和3的C-C'环中的两个保守KDG序列会产生γ-转角，这是脊椎动物免疫球蛋白高变区L2的C'-C''环中的常见基序。这些比较还显示了血淋巴蛋白及其与微生物实体相互作用的未来研究中特别感兴趣的可变区。
