Differential abilities of the mushroom ribosome-inactivating proteins hypsin and velutin to perturb normal development of cultured mouse embryos.
The teratogenicity of two fungal ribosome-inactivating proteins, hypsin from Hypsizigus mamoreus and velutin from Flammulina velutipes, was examined in this investigation using microinjection and postimplantation whole-embryo culture. The results demonstrated that hypsin induced abnormal embryonic development at 2.5 microM during the organogenesis period from E8.5 to E9.5. As its dosage increased, there was an increase in the total number of abnormal embryos, a drop in the final somite number, and a rise of abnormal structures. Structural abnormalities were detected: open cranial neural tube, abnormal branchial arches, absence of forelimb buds and twisted body axis. The otic and optic placodes were, however, less affected. Histological study of the abnormal embryos revealed a correlation of increased cell death with abnormal structures, suggesting that induction of cell death by hypsin may account for its teratogenicity. In contrast, velutin did not exert any adverse influence on mouse development.
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School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China. b021770@mailserv.cuhk.edu.hk
Lam
Joyce S Y
JS
Wong
Jack H
JH
Lam
S K
SK
Ngai
P H K
PH
Wang
H X
HX
Chu
K T
KT
Chan
W Y
WY
D000818:Animals; D004622:Embryo, Mammalian / Q000002:abnormalities / Q000187:drug effects / Q000648:ultrastructure; D047108:Embryonic Development / Q000187:drug effects*; D005656:Fungal Proteins / Q000633:toxicity*; D051379:Mice; D008813:Mice, Inbred ICR; D054788:Ribosome Inactivating Proteins / Q000633:toxicity*; D013723:Teratogens / Q000633:toxicity*
D005656:Fungal Proteins; D054788:Ribosome Inactivating Proteins; D013723:Teratogens; C425465:Velutin protein, Flammulina velutipes