Department of Medicine, University of Alberta, Edmonton, AB, Canada.
Dev Comp Immunol. 2012 Sep;38(1):30-43. doi: 10.1016/j.dci.2012.03.012. Epub 2012 Mar 30.
Here we describe the cloning and expression of Pekin duck IL-10 (duIL-10) and a six exon-5 intron structure of an IL-10 gene. Two transcripts encoding duIL-10 with an alternatively spliced 3'UTR, and a transcript lacking exon 5 with a novel coding sequence for its C-terminus (duIL-10ΔE5) were isolated from splenocytes. The duIL-10 protein has an amino acid identity of 79% and 47% with chicken and human IL-10, respectively. The duck IL-10 gene shares a similar structure of the respective exons 1-5 with the IL-10 genes of other vertebrates but has an alternative exon. The duIL-10 3D structure by homology modeling was similar to that of the human IL-10 monomer, whereas the predicted duIL-10ΔE5 protein lacks helix F. DuIL-10 and duIL-10ΔE5 transcripts were most abundant in primary and secondary immune organs and lung. Recombinant duIL-10 suppressed duck IL-2 transcripts in mitogen-activated PBMCs. Our observation suggests evolutionary conservation of structure and function of the duIL-10 protein but the roles of the novel IL-10 splice variants in the regulation of duck immune responses and evolution of vertebrate immunity remain to be elucidated.
我们在这里描述了北京鸭白细胞介素 10（duIL-10）的克隆和表达，以及 IL-10 基因的六外显子-5 内含子结构。从脾细胞中分离出两种编码带有交替剪接 3'UTR 的 duIL-10 的转录本，以及一种缺乏外显子 5 并具有其 C 末端新编码序列的转录本（duIL-10ΔE5）。duIL-10 蛋白与鸡和人 IL-10 的氨基酸同一性分别为 79%和 47%。鸭 IL-10 基因与其他脊椎动物的 IL-10 基因具有相似的外显子 1-5 结构，但具有替代外显子。通过同源建模的鸭 IL-10 3D 结构与人类 IL-10 单体相似，而预测的 duIL-10ΔE5 蛋白缺乏螺旋 F。duIL-10 和 duIL-10ΔE5 转录本在初级和次级免疫器官和肺中最为丰富。重组 duIL-10 抑制丝裂原激活的 PBMC 中的鸭 IL-2 转录本。我们的观察表明，duIL-10 蛋白的结构和功能在进化上是保守的，但新型 IL-10 剪接变体在调节鸭免疫反应和脊椎动物免疫进化中的作用仍有待阐明。
