Abstract
Gonad-stimulating substance (GSS) in starfish is the only known invertebrate peptide hormone responsible for final gamete maturation, rendering it functionally analogous to gonadotropins in vertebrates. Recently, we purified GSS from radial nerves in the starfish Asterina pectinifera and identified the chemical structure as a heterodimer composed of two different peptides (A- and B-chain) with disulfide cross-linkages. This study examined the hormonal action of GSS on ovarian follicle cells obtained from ovaries in growing (stage IV) and fully grown (stage V) stages, and particularly the mode of signal transduction. The action of GSS on 1-MeAde production by follicle cells in stage V was mediated through the production of cAMP. In contrast, GSS failed to induce 1-MeAde and cAMP production by follicle cells in stage IV. According to competitive experiments using radioiodinated and radioinert GSS, highly specific binding was observed in follicle cells, though their affinities and numbers in stage IV were inferior to those in stage V. Interestingly, Gsα was not detected immunologically in follicle cell membranes of stage IV. Gβ was also faint in stage IV. Although adenylyl cyclase activity in stage V was dose-dependently activated by GSS in the presence of GTP, neither GSS in the presence of GTP nor nonhydrolyzable GTP analogs were effective on the activity in stage IV. These findings strongly suggest that the failure of GSS to produce 1-MeAde is because of a lack of Gs-proteins in follicle cells at stage IV.
| Original language | English |
|---|---|
| Pages (from-to) | 432-437 |
| Number of pages | 6 |
| Journal | General and Comparative Endocrinology |
| Volume | 176 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2012 May 1 |
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Keywords
- 1-Methyladenine (1-MeAde)
- Adenylyl cyclase
- Gonad-stimulating substance (GSS)
- Gs-proteins
- Starfish
ASJC Scopus subject areas
- Endocrinology
Cite this
Participation of Gs-proteins in the action of relaxin-like gonad-stimulating substance (GSS) for 1-methyladenine production in starfish ovarian follicle cells. / Mita, Masatoshi; Yamamoto, Kazutoshi; Nakamura, Masaru; Takeshige, Yuki; Watanabe, Miho; Nagahama, Yoshitaka.
In: General and Comparative Endocrinology, Vol. 176, No. 3, 01.05.2012, p. 432-437.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Participation of Gs-proteins in the action of relaxin-like gonad-stimulating substance (GSS) for 1-methyladenine production in starfish ovarian follicle cells
AU - Mita, Masatoshi
AU - Yamamoto, Kazutoshi
AU - Nakamura, Masaru
AU - Takeshige, Yuki
AU - Watanabe, Miho
AU - Nagahama, Yoshitaka
PY - 2012/5/1
Y1 - 2012/5/1
N2 - Gonad-stimulating substance (GSS) in starfish is the only known invertebrate peptide hormone responsible for final gamete maturation, rendering it functionally analogous to gonadotropins in vertebrates. Recently, we purified GSS from radial nerves in the starfish Asterina pectinifera and identified the chemical structure as a heterodimer composed of two different peptides (A- and B-chain) with disulfide cross-linkages. This study examined the hormonal action of GSS on ovarian follicle cells obtained from ovaries in growing (stage IV) and fully grown (stage V) stages, and particularly the mode of signal transduction. The action of GSS on 1-MeAde production by follicle cells in stage V was mediated through the production of cAMP. In contrast, GSS failed to induce 1-MeAde and cAMP production by follicle cells in stage IV. According to competitive experiments using radioiodinated and radioinert GSS, highly specific binding was observed in follicle cells, though their affinities and numbers in stage IV were inferior to those in stage V. Interestingly, Gsα was not detected immunologically in follicle cell membranes of stage IV. Gβ was also faint in stage IV. Although adenylyl cyclase activity in stage V was dose-dependently activated by GSS in the presence of GTP, neither GSS in the presence of GTP nor nonhydrolyzable GTP analogs were effective on the activity in stage IV. These findings strongly suggest that the failure of GSS to produce 1-MeAde is because of a lack of Gs-proteins in follicle cells at stage IV.
AB - Gonad-stimulating substance (GSS) in starfish is the only known invertebrate peptide hormone responsible for final gamete maturation, rendering it functionally analogous to gonadotropins in vertebrates. Recently, we purified GSS from radial nerves in the starfish Asterina pectinifera and identified the chemical structure as a heterodimer composed of two different peptides (A- and B-chain) with disulfide cross-linkages. This study examined the hormonal action of GSS on ovarian follicle cells obtained from ovaries in growing (stage IV) and fully grown (stage V) stages, and particularly the mode of signal transduction. The action of GSS on 1-MeAde production by follicle cells in stage V was mediated through the production of cAMP. In contrast, GSS failed to induce 1-MeAde and cAMP production by follicle cells in stage IV. According to competitive experiments using radioiodinated and radioinert GSS, highly specific binding was observed in follicle cells, though their affinities and numbers in stage IV were inferior to those in stage V. Interestingly, Gsα was not detected immunologically in follicle cell membranes of stage IV. Gβ was also faint in stage IV. Although adenylyl cyclase activity in stage V was dose-dependently activated by GSS in the presence of GTP, neither GSS in the presence of GTP nor nonhydrolyzable GTP analogs were effective on the activity in stage IV. These findings strongly suggest that the failure of GSS to produce 1-MeAde is because of a lack of Gs-proteins in follicle cells at stage IV.
KW - 1-Methyladenine (1-MeAde)
KW - Adenylyl cyclase
KW - Gonad-stimulating substance (GSS)
KW - Gs-proteins
KW - Starfish
UR - http://www.scopus.com/inward/record.url?scp=84859903713&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84859903713&partnerID=8YFLogxK
U2 - 10.1016/j.ygcen.2011.11.010
DO - 10.1016/j.ygcen.2011.11.010
M3 - Article
VL - 176
SP - 432
EP - 437
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
SN - 0016-6480
IS - 3
ER -