TY - JOUR
T1 - Sperm nuclear decondensation in mammals
T2 - Role of sperm‐associated proteinase in vivo
AU - Perreault, Sally D.
AU - Zirkin, Barry R.
PY - 1982/12/10
Y1 - 1982/12/10
N2 - Previous studies from this (Zirkin et al., '80) and other (Marushige and Marushige, '78) laboratories have shown that proteinase associated with mammalian sperm nuclei is involved in thiol‐induced sperm nuclear decondensation and protamine degradation in vitro. The results of these in vitro studies suggested the exciting possibility that the sperm nucleus itself might contribute proteinase involved in its subsequent in vivo decondensation during fertilization. In the present study, microinjection methods were used to test this possibility directly. Control hamster sperm nuclei, which exhibited proteinase activity, decondensed when incubated in vitro with disulfide reducing agent. As expected, these nuclei also decondensed when microinjected into ovulated hamster oocytes and formed morphologically normal pronuclei. When the proteinase associated with isolated sperm nuclei was removed with 0.5 M salt or inhibited with nitrophenyl‐p‐guanidinobenzoate, the nuclei were rendered incapable of decondensing in response to disulfide reducing agent in vitro. However, when these nuclei were microinjected into eggs, they decondensed and transformed into pronuclei. These results provide direct evidence that sperm‐associated proteinase is not required for sperm nuclear decondensation and formation of the male pronucleus during fertilization.
AB - Previous studies from this (Zirkin et al., '80) and other (Marushige and Marushige, '78) laboratories have shown that proteinase associated with mammalian sperm nuclei is involved in thiol‐induced sperm nuclear decondensation and protamine degradation in vitro. The results of these in vitro studies suggested the exciting possibility that the sperm nucleus itself might contribute proteinase involved in its subsequent in vivo decondensation during fertilization. In the present study, microinjection methods were used to test this possibility directly. Control hamster sperm nuclei, which exhibited proteinase activity, decondensed when incubated in vitro with disulfide reducing agent. As expected, these nuclei also decondensed when microinjected into ovulated hamster oocytes and formed morphologically normal pronuclei. When the proteinase associated with isolated sperm nuclei was removed with 0.5 M salt or inhibited with nitrophenyl‐p‐guanidinobenzoate, the nuclei were rendered incapable of decondensing in response to disulfide reducing agent in vitro. However, when these nuclei were microinjected into eggs, they decondensed and transformed into pronuclei. These results provide direct evidence that sperm‐associated proteinase is not required for sperm nuclear decondensation and formation of the male pronucleus during fertilization.
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U2 - 10.1002/jez.1402240215
DO - 10.1002/jez.1402240215
M3 - Article
C2 - 6759610
AN - SCOPUS:0020479876
SN - 0022-104X
VL - 224
SP - 253
EP - 257
JO - Journal of Experimental Zoology
JF - Journal of Experimental Zoology
IS - 2
ER -