Impairment of lower jaw growth in developing zebrafish exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin and reduced hedgehog expression

被引:26
作者
Teraoka, Hiroki [1 ]
Dong, Wu
Okuhara, Yuji
Lwasa, Hiroyuki
Shindo, Asako
Hill, Adrian J.
Kawakami, Atsushi
Hiraga, Takeo
机构
[1] Rakuno Gakuen Univ, Sch Vet Med, Dept Toxicol, Ebetsu, Hokkaido 0698501, Japan
[2] Inner Mongolia Univ Nationalities, Coll Anim Sci & Technol, Tongliao, Peoples R China
[3] Univ Wisconsin, Sch Pharm, Madison, WI 53706 USA
[4] Univ Tokyo, Dept Biol, Tokyo 153, Japan
关键词
cell proliferation; craniofacial malformation; dioxin; hedgehog; TCDD; zebrafish;
D O I
10.1016/j.aquatox.2006.02.009
中图分类号
Q17 [水生生物学];
学科分类号
071004 ;
摘要
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) has been shown to cause a multitude of detrimental effects to developing zebrafish (Danio rerio). Previously, we demonstrated that jaw growth was impaired by TCDD exposure, but the exact mechanism underlying these malformations remained unknown. In the present study, we investigated the involvement of hedgehog genes and their downstream signaling in TCDD-mediated jaw malformation. We demonstrate that the developing lower jaw expresses sonic hedgehog a (shha), sonic hedgehog b (shhb) and their receptors, patched1 (ptc1) and patched2 (ptc2), as well as the downstream transcription factors, gli1 and gli2a. Loss of Hh signaling in mutants (sonic you) and larvae treated with a Hh inhibitor (cyclopamine), resulted in similar effects as those caused by TCDD. Moreover, TCDD exposure caused downregulation of shha and shhb in a manner dependent on aryl hydrocarbon receptor 2 (ahr2). Although this suggested an involvement of Hh signaling in TCDD-mediated impairment of jaw growth, we did not observe downregulation of ptc1 and ptc2, receptors dependent on Hh signaling. Furthermore, while the overall occurrence of apoptosis in the developing jaw was minimal, it was significantly increased in larvae treated with cyclopamine. In contrast, both TCDD and cyclopamine markedly reduced immunoreactivity against phosphorylated histone 3, a cell proliferation marker in the developing jaw. Taken together, our data suggest that Ahr2-mediated downregulation of Hh signaling, leading to a failure of cell proliferation, contributes to TCDD induced inhibition of lower jaw growth. TCDD may impair jaw growth through other pathway(s) in addition to Hh signaling. (c) 2006 Elsevier B.V. All rights reserved.
引用
收藏
页码:103 / 113
页数:11
相关论文
共 58 条
  • [51] Induction of cytochrome P450 1A is required for circulation failure and edema by 2,3,7,8-tetrachlorodibenzo-p-dioxin in zebrafish
    Teraoka, H
    Dong, W
    Tsujimoto, Y
    Iwasa, H
    Endoh, D
    Ueno, N
    Stegeman, JJ
    Peterson, RE
    Hiraga, T
    [J]. BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 2003, 304 (02) : 223 - 228
  • [52] Gene interaction network suggests dioxin induces a significant linkage between aryl hydrocarbon receptor and retinoic acid receptor beta
    Toyoshiba, H
    Yamanaka, T
    Sone, H
    Parham, FM
    Walker, NJ
    Martinez, J
    Portier, CJ
    [J]. ENVIRONMENTAL HEALTH PERSPECTIVES, 2004, 112 (12) : 1217 - 1224
  • [53] WADA N, 2004, 6 INT C ZEBR DEV GEN, P588
  • [54] Walker Mary K., 1994, P347
  • [55] Functional characterization of aryl hydrocarbon receptor (zfAHR2) localization and degradation in zebrafish (Danio rerio)
    Wentworth, JN
    Buzzeo, R
    Pollenz, RS
    [J]. BIOCHEMICAL PHARMACOLOGY, 2004, 67 (07) : 1363 - 1372
  • [56] Westerfield M., 1995, ZEBRAFISH BOOK GUIDE
  • [57] Whitlock KE, 2000, DEVELOPMENT, V127, P3645
  • [58] cDNA cloning and expressions of cytochrome P450 1A in zebrafish embryos
    Yamazaki, K
    Teraoka, H
    Dong, W
    Stegeman, JJ
    Hiraga, T
    [J]. JOURNAL OF VETERINARY MEDICAL SCIENCE, 2002, 64 (09) : 829 - 833