BmCDK5 Affects Cell Proliferation and Cytoskeleton Morphology by Interacting with BmCNN in Bombyx mori.

Cyclin-dependent kinases (CDKs), as biological macromolecules, play key regulatory roles in the cell cycle process. Cyclin-dependent kinase-5 (CDK5) is part of the CDK family; however, its effect on cell cycle progression is controversial and the mechanism remains unclear. In this article, we identified a homologous gene of the Cyclin-dependent kinase family, BmCDK5, in the silkworm, Bombyx mori. We proved that the BmCDK5 gene can regulate the cell cycle and promote cell proliferation in BmNS cells. Furthermore, we demonstrated that BmCDK5 can interact with BmCNN, and that they both affect cytoskeleton morphology but do not induce changes in microtubule protein expression; they can also promote cell proliferation. The ordered cell cycle is important to the proliferation and differentiation of living organisms. Cyclin-dependent kinases (CDKs) perform regulatory functions in different phases of the cell cycle process to ensure order. We identified a homologous gene of the Cyclin-dependent kinase family, BmCDK5, in Bombyx mori. BmCDK5 contains the STKc_CDK5 domain. The BmCDK5 gene was highly expressed in S phase. Overexpression of the BmCDK5 gene accelerates the process of the cell cycle’s mitotic period (M) and promotes cell proliferation; knocking out the BmCDK5 gene inhibited cell proliferation. Furthermore, we identified a protein, BmCNN, which can interact with BmCDK5 and represents the same express patterns as the BmCDK5 gene in the cell cycle phase and the spatial-temporal expression of B. mori. This study revealed that BmCDK5 and BmCNN play roles in promoting cell proliferation and regulating cytoskeleton morphology, but do not induce expression changes in microtubule protein. Therefore, our findings provide a new insight; the BmCDK5 gene has a regulatory effect on the cell cycle and proliferation of B. mori, which is presumably due to the interaction between BmCDK5 and BmCNN regulating changes in the cytoskeleton.

细胞周期蛋白依赖性激酶（CDKs）作为生物大分子，在细胞周期过程中起着关键的调节作用。细胞周期蛋白依赖性激酶5（CDK5）是CDK家族的一员；然而，其对细胞周期进程的影响存在争议，且机制尚不清楚。在本文中，我们在蚕（Bombyx mori）中鉴定出了细胞周期蛋白依赖性激酶家族的一个同源基因BmCDK5。我们证明了BmCDK5基因能够调节细胞周期并促进家蚕神经干细胞（BmNS细胞）的增殖。此外，我们还证明了BmCDK5能够与BmCNN相互作用，并且它们都影响细胞骨架形态，但不会诱导微管蛋白表达的变化；它们也能够促进细胞增殖。 有序的细胞周期对生物体的增殖和分化非常重要。细胞周期蛋白依赖性激酶（CDKs）在细胞周期过程的不同阶段发挥调节功能以确保其有序性。我们在蚕中鉴定出了细胞周期蛋白依赖性激酶家族的一个同源基因BmCDK5。BmCDK5包含STKc_CDK5结构域。BmCDK5基因在S期高表达。BmCDK5基因的过表达加速了细胞周期有丝分裂期（M期）的进程并促进细胞增殖；敲除BmCDK5基因则抑制细胞增殖。此外，我们鉴定出了一种蛋白质BmCNN，它能够与BmCDK5相互作用，并且在蚕的细胞周期阶段以及时空表达上与BmCDK5基因呈现相同的表达模式。这项研究表明，BmCDK5和BmCNN在促进细胞增殖和调节细胞骨架形态方面发挥作用，但不会诱导微管蛋白的表达变化。因此，我们的研究结果提供了一个新的见解：BmCDK5基因对蚕的细胞周期和增殖具有调节作用，这可能是由于BmCDK5和BmCNN之间的相互作用调节了细胞骨架的变化。