Synchronized expression of two caspase family genes, ice-2 and ice-5, in hydrogen peroxide-induced cells of the silkworm, Bombyx mori
1Institute of Life Sciences, Jiangsu University, Zhenjiang 212013, China
2School of Life Sciences, Soochow University, Suzhou 215123, China
Abstract
Caspase family proteins play important roles in different stages of the apoptotic pathway. To date, however, functions of Bombyx mori L. (Lepidoptera: Bombycidae) caspase family genes are poorly known. This paper focuses on the morphology, mitochondrial membrane potential, and expression profiles of two novel B. mori caspase family genes (ice-2 and ice-5) in 3 µM hydrogen peroxide (H2O2) damaged B. mori cells, which were separated from the ovary of B. mori. In addition, comparisons were made between damage caused by H2O2 and by ultraviolet (UV) irradiation. The results showed that the potential change of the mitochondrial membrane occurred at 0.5 h after H2O2 stimulation, which was sooner than occurred in the UV treated model where the obvious decrease appeared at 6 h after stimulation. In addition, the total change in the potential of the mitochondrial membrane in H2O2 treated B. mori cells was larger than with UV treated cells during the whole process. Analysis of fluorescent quantitative real-time PCR demonstrated that ice-2 and ice-5 might be involved in both H2O2 and UV-induced apoptosis in B. mori cells. Notably, after exposure to H2O2, the expression patterns of ice-5 were remarkably higher than those of ice-2, while the result was the opposite after exposure to UV irradiation. The data indicate that apoptosis induced by H2O2 was directly related to the mitochondrial pathway. The two isoforms of B. mori ice may play different roles in the mitochondrion associated apoptotic pathway in B. mori cells, and the apoptotic pathway in H2O2 induced B. mori cells is different from the UV induced apoptotic pathway.
Keywords: apoptosis; ultraviolet irradiation
Correspondence:
aying_sun@163.com,
bwenbingwang@ujs.edu.cn,
csdlibing@hotmail.com,
dzengbin@gmail.com,
ehuiling@ujs.edu.cn,
fshenwd@suda.edu.cn
Associate Editor: Kostas Iatrou was editor of this paper
Received: 27 September 2008 | Accepted: 18 November 2008 | Published: 8 May 2010
Copyright: This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.
ISSN: 1536-2442 | Volume 10, Number 43
Sun Y, Wang W, Li B, Wu Y, Wu H, Shen W. 2010. Synchronized expression of two caspase family genes, ice-2 and ice-5, in hydrogen peroxide-induced cells of the silkworm, Bombyx mori. 10pp. Journal of Insect Science 10:43, available online: insectscience.org/10.43
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