State Key Laboratory of Rice Biology, and Molecular Biology of Crop Pathogens and Insects, The Ministry of Agriculture of China.
Biochimie. 2011 Jul;93(7):1124-31. doi: 10.1016/j.biochi.2011.03.009. Epub 2011 Mar 30.
Ceramidase plays an important role in regulating the metabolism of sphingolipids, such as ceramide, sphingosine (SPH), and sphingosine-1-phosphate (S1P), by controlling the hydrolysis of ceramide. Here we report the cloning and biochemical characterization of a neutral ceramidase from the red flour beetle Tribolium castaneum which is an important storage pest. The Tribolium castaneum neutral ceramidase (Tncer) is a protein of 696 amino acids. It shares a high degree of similarity in protein sequence to neutral ceramidases from various species. Tncer mRNA levels are higher in the adult stage than in pre-adult stages, and they are higher in the reproductive organs than in head, thorax, and midgut. The mature ovary has higher mRNA levels than the immature ovary. Tncer is localized to the plasma membrane. It uses various ceramides (D-erythro-C(6), C(12), C(16), C(18:1), and C(24:1)-ceramide) as substrates and has an abroad pH optimum for its in vitro activity. Tncer has an optimal temperature of 37 °C for its in vitro activity. Its activity is inhibited by Fe(2+). These results suggest that Tncer has distinct biochemical properties from neutral ceramidases from other species.
神经酰胺酶在调节神经酰胺、鞘氨醇（SPH）和鞘氨醇-1-磷酸（S1P）等鞘脂代谢方面发挥着重要作用，通过控制神经酰胺的水解来实现。在这里，我们报告了来自重要仓储害虫赤拟谷盗的中性神经酰胺酶的克隆和生化特性。赤拟谷盗中性神经酰胺酶（Tncer）是一种 696 个氨基酸的蛋白质。它与来自不同物种的中性神经酰胺酶在蛋白质序列上具有高度相似性。Tncer mRNA 水平在成虫期高于幼体期，在生殖器官中高于头部、胸部和中肠。成熟卵巢的 mRNA 水平高于未成熟卵巢。Tncer 定位于质膜。它使用各种神经酰胺（D-erythro-C（6）、C（12）、C（16）、C（18:1）和 C（24:1）-神经酰胺）作为底物，其体外活性具有广泛的 pH 最佳值。Tncer 的体外活性最佳温度为 37°C。其活性受到 Fe（2+）的抑制。这些结果表明，Tncer 具有与其他物种的中性神经酰胺酶明显不同的生化特性。
