Adameyko K I, Kravchuk O I, Finoshin A D, Bonchuk A N, Georgiev A A, Mikhailov V S, Gornostaev N G, Mikhailov K V, Bacheva A V, Indeykina M I, Bugrova A E, Gazizova G R, Kozlova O S, Gusev O A, Shagimardanova E I, Lyupina Y V
Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, 119334 Russia.
Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334 Russia.
Mol Biol (Mosk). 2020 May-Jun;54(3):474-479. doi: 10.31857/S0026898420030039.
The iron-containing protein neuroglobin (Ngb) involved in the transport of oxygen is generally considered the precursor of all animal globins. In this report, we studied the structure of Ngb of the cold-water sponge Halisarca dujardinii. In sponges, the oldest multicellular organisms, the Ngb gene contains three introns. In contrast to human Ngb, its promoter contains a TATA-box, rather than CG-rich motifs. In sponges, Ngb consists of 169 amino acids showing rather low similarity with its mammalian orthologues. It lacks Glu and Arg residues in positions required for prevention of hypoxia-related apoptosis. Nevertheless, Ngb contains both proximal and distal conserved heme-biding histidines. The primary structure of H. dujardinii neuroglobin predicted by sequencing was confirmed by mass-spectrometry analysis of recombinant Ngb expressed in E. coli. The high level of Ngb expression in sponge tissues suggests its possible involvement in the gas metabolism and presumably in other key metabolic processes in H. dujardinii.
参与氧气运输的含铁蛋白神经球蛋白（Ngb）通常被认为是所有动物球蛋白的前体。在本报告中，我们研究了冷水海绵杜氏盐海绵（Halisarca dujardinii）的Ngb结构。在海绵这种最古老的多细胞生物中，Ngb基因包含三个内含子。与人类Ngb不同，其启动子含有一个TATA框，而非富含CG的基序。在海绵中，Ngb由169个氨基酸组成，与哺乳动物的同源物相似度相当低。它在预防缺氧相关凋亡所需的位置缺乏Glu和Arg残基。然而，Ngb同时含有近端和远端保守的血红素结合组氨酸。通过对在大肠杆菌中表达的重组Ngb进行质谱分析，证实了通过测序预测的杜氏盐海绵神经球蛋白的一级结构。海绵组织中Ngb的高表达水平表明其可能参与杜氏盐海绵的气体代谢以及可能的其他关键代谢过程。
