TY - JOUR
T1 - Aromatase immunoreactivity and the role of enzymes in steroid pathways for inducing sex change in the hermaphrodite gobiid fish Trimma okinawae
AU - Sunobe, Tomoki
AU - Nakamura, Masaru
AU - Kobayashi, Yasuhisa
AU - Kobayashi, Tohru
AU - Nagahama, Yoshitaka
N1 - Funding Information:
We are grateful to Drs. M. Abe and S. Higashi of Faculty of Science and Drs. H. Manabe and A. Shinomiya of Faculty of Fisheries, Kagoshima University, for their assistance during this study. Thanks are also due to P.L. Munday for his kind review of the manuscript. This study is partly supported by the 21st Century COE program of the University of the Ryukyus and a Grant-in-Aid for Scientific Research (C16570025) from Ministry of Education, Culture, Sports, Science and Technology, Japan to T.S.
PY - 2005/5
Y1 - 2005/5
N2 - The role of aromatase (Arom) in the process of bi-directional sex change in the gobiid fish Trimma okinawae was investigated by immunohistochemical methods. Irrespective of sexual phase, gonads comprised both ovarian and testicular tissues. In each sexual phase of females, the 2nd (2DF-M) and 4th (4DF-M) days after initiation of sex change to male, males, and the 2nd (2DM-F), 4th (4DM-F) and 6th (6DM-F) days after the initiation of reversion from male to female, ovarian and testicular histological observations were made. During the female, 2DF-M, 4DF-M and 6DM-F phases, the ovary contained vitellogenic and previtellogenic oocytes, compared with previtellogenic oocytes in the other phases. Although sperm was found in the testis in every phase, sperm ducts were apparent in the male phase, but not the female phase. Arom immunoreactivity was detected in the interstitial cells between the oocytes in all phases. On the other hand, it was localized in the thecal and granulosa cells of the follicular layer enclosing the oocytes in the female, 2DF-M, 4DF-M and 6DM-F phases. Activity of Arom in the thecal and granulosa cells is thought to be important for the development of oocytes and subsequent sex change.
AB - The role of aromatase (Arom) in the process of bi-directional sex change in the gobiid fish Trimma okinawae was investigated by immunohistochemical methods. Irrespective of sexual phase, gonads comprised both ovarian and testicular tissues. In each sexual phase of females, the 2nd (2DF-M) and 4th (4DF-M) days after initiation of sex change to male, males, and the 2nd (2DM-F), 4th (4DM-F) and 6th (6DM-F) days after the initiation of reversion from male to female, ovarian and testicular histological observations were made. During the female, 2DF-M, 4DF-M and 6DM-F phases, the ovary contained vitellogenic and previtellogenic oocytes, compared with previtellogenic oocytes in the other phases. Although sperm was found in the testis in every phase, sperm ducts were apparent in the male phase, but not the female phase. Arom immunoreactivity was detected in the interstitial cells between the oocytes in all phases. On the other hand, it was localized in the thecal and granulosa cells of the follicular layer enclosing the oocytes in the female, 2DF-M, 4DF-M and 6DM-F phases. Activity of Arom in the thecal and granulosa cells is thought to be important for the development of oocytes and subsequent sex change.
KW - Estradiol-17β
KW - Gobiidae
KW - Hermaphroditism
KW - Immunohistochemistry
KW - Sex change
KW - Steroid pathways
KW - Trimma okinawae
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U2 - 10.1016/j.cbpb.2005.03.012
DO - 10.1016/j.cbpb.2005.03.012
M3 - Article
C2 - 15916910
AN - SCOPUS:20444404915
SN - 1095-6433
VL - 141
SP - 54
EP - 59
JO - Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology
JF - Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology
IS - 1
ER -