摘要

Naturally fertilized Microhyla ornatu and Xenopus laevis embryos at dorsal lip of blastopore stage were exposed to 0.3, and 0.6% sodium chloride for high salinity treatment and dilute hydrochloric acid and sodium hydroxide for treatment with low and high pH, respectively. After treatment for different durations, embryos were studied morphologically and using in situ hybridization with selected genes important for normal development and for coping with environmental stress. Altered salinity and pH caused defects in axis formation and neural tube closure, delay in hatching, abnormal swimming of tadpoles and even developmental arrest. This was accompanied by significant decrease in the expression of selected development-regulating genes like goosecoid (required for gastrulation movements), brachyury (mesodermal marker gene), noggin (involved in neural induction), NCAM (required for neural cell adhesion) and MyoD (essential for muscle development), and considerable increase in the transcription of stress response genes hsp30 and hsp70. Altering the expression of embryonic genes could be one of the mechanisms through which environmental factors influence development of amphibian embryos.

  • 出版日期2012-8