TY - JOUR
T1 - Differentiation of ambisexual gonads and immunohistochemical localization of P450 cholesterol side-chain cleavage enzyme during gonadal sex differentiation in the protandrous anemonefish, Amphiprion clarkii
AU - Miura, Saori
AU - Nakamura, Shigeo
AU - Kobayashi, Yasuhisa
AU - Piferrer, Francesc
AU - Nakamura, Masaru
N1 - Funding Information:
We thank Dr. Satoshi Awata for his valuable comments and suggestions on an earlier draft of the manuscript. We are indebted to the staff of the Sesoko Station at the Tropical Biosphere Research Center (TBRC), University of the Ryukyus, and the staff of the National Center for Stock Enhancement for their support in fish maintenance. We are also grateful to many students at the TBRC for their encouragement, help and advice. SM was supported by Research Fellowships the Japan Society for the Promotion of Science for Young Scientists. The work of FP at the TBRC was supported by a 21st Century COE grant from the University of the Ryukyus in Okinawa. This study was partially supported in part by the Ministry of Education, Culture, Sports, and Technology of Japan (MN) and by a 21st Century COE grant entitled “The Comprehensive Analyses on Biodiversity in Coral Reef and Island Ecosystems in Asian and Pacific Regions” from the University of the Ryukyus in Okinawa (MN and YK).
PY - 2008/1
Y1 - 2008/1
N2 - To clarify the relationship between steroid hormones and sex differentiation of the protandrous anemonefish Amphiprion clarkii, we histologically examined its gonadal differentiation. From hatching to 30 days post hatching (dph), all of the gonads surveyed were sexually undifferentiated. The gonads of all fish first differentiated into ovaries at 60 dph, and the oocytes gradually developed and increased in number as the ovaries grew up until 183 dph. Some cysts of differentiated spermatogenic germ cells appeared in the ovaries at 214 dph, and ambisexual gonads with both ovarian and testicular tissues formed by 273 dph. Using immunohistochemistry, we then investigated the expression of cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), during gonadal sex differentiation. P450scc-immunopositive reactions first appeared in sexually undifferentiated gonads at 30 dph. Beginning at 60 dph, the number of strongly positive cells increased throughout the differentiation of the ovaries and continued to increase during the testicular differentiation until 210 dph. Immunopositive cells were observed more frequently in ovarian tissue than in testicular tissue in the ambisexual gonads at 270 dph. These results suggest that endogenous steroid hormones are important for the sex differentiation, including the primary sex differentiation and subsequent testicular differentiation, of the anemonefish.
AB - To clarify the relationship between steroid hormones and sex differentiation of the protandrous anemonefish Amphiprion clarkii, we histologically examined its gonadal differentiation. From hatching to 30 days post hatching (dph), all of the gonads surveyed were sexually undifferentiated. The gonads of all fish first differentiated into ovaries at 60 dph, and the oocytes gradually developed and increased in number as the ovaries grew up until 183 dph. Some cysts of differentiated spermatogenic germ cells appeared in the ovaries at 214 dph, and ambisexual gonads with both ovarian and testicular tissues formed by 273 dph. Using immunohistochemistry, we then investigated the expression of cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), during gonadal sex differentiation. P450scc-immunopositive reactions first appeared in sexually undifferentiated gonads at 30 dph. Beginning at 60 dph, the number of strongly positive cells increased throughout the differentiation of the ovaries and continued to increase during the testicular differentiation until 210 dph. Immunopositive cells were observed more frequently in ovarian tissue than in testicular tissue in the ambisexual gonads at 270 dph. These results suggest that endogenous steroid hormones are important for the sex differentiation, including the primary sex differentiation and subsequent testicular differentiation, of the anemonefish.
KW - Ambisexual gonads
KW - Anemonefish
KW - Immunohistochemistry
KW - Protandry
KW - Sex differentiation
KW - Steroidogenic enzyme
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U2 - 10.1016/j.cbpb.2007.08.002
DO - 10.1016/j.cbpb.2007.08.002
M3 - Article
C2 - 17919957
AN - SCOPUS:36749031193
SN - 1096-4959
VL - 149
SP - 29
EP - 37
JO - Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology
JF - Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology
IS - 1
ER -