Institute of Biochemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China ; Zhejiang Provincial Key Laboratroy of Silkworm Bioreactor and Biomedicine, Hangzhou 310018, China.
Int J Genomics. 2013;2013:323592. doi: 10.1155/2013/323592. Epub 2013 Jun 3.
The 30K family of proteins is important in energy metabolism and may play a role in inhibiting cellular apoptosis in silkworms (Bombyx mori). Several 30K-family proteins have been identified. In this study, two new silkworm genes, referred to as Slp (NM 001126256) and Lsp-t (NM 001043443), were analyzed by a bioinformatics approach according to the sequences of 30K proteins previously reported in the silkworm. Both Slp and Lsp-t shared more than 41% amino acid sequence homology with the reported 30K proteins and displayed a conserved domain consistent with that of lipoprotein-11. Additionally, the cDNA sequences of both Slp and Lsp-t were obtained from the fat bodies of silkworm larvae by reverse transcription polymerase chain reaction. Both genes were expressed in BmN cells using the Bac-to-Bac system. Purified Slp and Lsp-t were added to cultured BmN and human umbilical vein endothelial cells (HUVEC) that were treated with H2O2. Both Slp and Lsp-t significantly enhanced the viability and suppressed DNA fragmentation in H2O2 treated BmN and HUVEC cells. This study suggested that Slp and Lsp-t exhibit similar biological activities as their known 30K-protein counterparts and mediate an inhibitory effect against H2O2-induced apoptosis.
30K 蛋白家族在能量代谢中起着重要作用，可能在抑制家蚕（Bombyx mori）细胞凋亡中发挥作用。已经鉴定出几种 30K 家族蛋白。在这项研究中，根据先前在蚕中报道的 30K 蛋白序列，通过生物信息学方法分析了两个新的家蚕基因，称为 Slp（NM 001126256）和 Lsp-t（NM 001043443）。Slp 和 Lsp-t 与报道的 30K 蛋白的氨基酸序列同源性均超过 41%，并显示出与脂蛋白-11 一致的保守结构域。此外，通过反转录聚合酶链反应从家蚕幼虫的脂肪体中获得了 Slp 和 Lsp-t 的 cDNA 序列。使用 Bac-to-Bac 系统在家蚕细胞系 BmN 中表达了这两个基因。纯化的 Slp 和 Lsp-t 被添加到用 H2O2 处理的培养的 BmN 和人脐静脉内皮细胞（HUVEC）中。Slp 和 Lsp-t 均显著提高了 H2O2 处理的 BmN 和 HUVEC 细胞的活力，并抑制了 DNA 片段化。这项研究表明，Slp 和 Lsp-t 表现出与其已知的 30K 蛋白对应物相似的生物学活性，并介导对 H2O2 诱导的细胞凋亡的抑制作用。
