Twist is required for muscle development of the adult legs in Henosepilachna vigintioctopunctata.

Although muscle development has been widely studied in Drosophila melanogaster, it was a great challenge to apply to developmental processes of other insect muscles. This study was focused on the functional characterization of a basic helix-loop-helix transcription factor gene twist in an herbivorous ladybird Henosepilachna vigintioctopunctata. Its transcript (Hvtwist) levels were detected in all developmental stages. RNA interference (RNAi)-aided knockdown of Hvtwist at the penultimate larval instar stage impaired pupation, and caused a deformed adult in the legs. The tarsi were malformed and did not support the bodies in an upright position. The climbing ability was impaired. Moreover, around 50% of the impaired adults had a malformed elytrum. In addition, they consumed less foliage and did not lay eggs. A hematoxylin-eosin staining of the leg demonstrated that the tibial extensor (TE) and the tibial flexor (TF) muscles were originated from the femurs while levator and depressor muscles of the tarsus (TL and TD) were located in the tibia in the control adults, in which tarsal segments were devoid of muscles. RNAi treatment specific to Hvtwist expression markedly impaired TE and TF muscles in the femurs, and prevented the development of TL and TD muscles in the tibia. Therefore, our findings demonstrate Twist plays a vital role in the myogenesis in H. vigintioctopunctata adult legs.

[Yishen Tonglong Decoction inhibits the epithelial-mesenchymal transition and Ras/ERK signaling pathway in human prostate cancer DU-145 cells].

Objective: To observe the effect of Yishen Tonglong Decoction (YTD) on the epithelial-mesenchymal transition (EMT) and Ras/ERK signaling pathway in human PCa DU-145 cells and explore its action mechanism. METHODS: We treated human PCa DU-145 cells with normal plasma (the blank control) or plasma containing 5% (low-dose), 10% (medium-dose) and 15% (high-dose) YTD. After intervention, we examined the proliferation of the DU-145 cells in different groups with CCK-8 and their apoptosis by Annexin V/PI double staining. We detected the cell cycle by PI assay, the invasion and migration of the cells using the Transwell chamber and scratch test, and the expressions of the proteins and genes related to the EMT and Ras/ERK signaling pathways in the cells by Western blot and RT-PCR. RESULTS: Compared with the blank control group, high-, medium- and low-dose YTD significantly inhibited the proliferation of the PCa DU-145 cells, decreased their adherence and growth (P < 0.05, P < 0.01), promoted their apoptosis (P < 0.01), regulated their cell cycles (P < 0.05, P < 0.01), and reduced their in vitro invasion and migration abilities (P < 0.05), all in a dose-dependent manner. The results of Western blot and RT-PCR revealed down-regulated protein and mRNA expressions of N-cadherin, zinc finger transcription factor (Snail), Ras, p-ERK1/2 and ERK1/2, but up-regulated protein and mRNA expressions of E-cadherin in the PCa DU-145 cells treated with YTD (P < 0.05, P < 0.01). CONCLUSIONS: Yishen Tonglong Decoction can effectively inhibit the proliferation, promote the apoptosis, regulate the cell cycle and suppress the invasion and migration abilities and EMT process of human PCa DU-145 cells. The mechanism of Yishen Tonglong Decoction acting on PCa may be associated with its inhibitory effect on the EMT process and expression of the Ras/ERK signaling pathway in PCa cells./.