TY - JOUR
T1 - Changes in ovarian gene expression profiles and plasma hormone levels in maturing European eel (Anguilla anguilla); Biomarkers for broodstock selection
AU - Burgerhout, Erik
AU - Minegishi, Yuki
AU - Brittijn, Sebastiaan A.
AU - de Wijze, Danielle L.
AU - Henkel, Christiaan V.
AU - Jansen, Hans J.
AU - Spaink, Herman P.
AU - Dirks, Ron P.
AU - van den Thillart, Guido E.E.J.M.
N1 - Funding Information:
The authors would like to thank Mieke and John van Dooren (Passie voor Vis, Sevenum, The Netherlands) for providing the female eels. Gerda Lamers is thanked for her assistance during histological analysis. This study was supported by grants from the Dutch Ministry of Economic Affairs/SenterNovem (Grant No. 359 SII081030 ) and from the EU Commission (PROEEL, Grant Agreement No. 245257 ).
Publisher Copyright:
© 2015 Elsevier Inc.
PY - 2016/1/1
Y1 - 2016/1/1
N2 - Complete sexual maturation of European eels (Anguilla anguilla) in captivity can only be achieved via injections with gonadotropins. For female eels this procedure takes 4-6. months and the response ranges from "unresponsive" to final maturation and ovulation. Reproductive success could be significantly increased via early selection of responders based on predictive markers and minimally invasive sampling methods. To get a better understanding of the genetic background of ovarian maturation of the European eel we performed a pilot deep-sequencing transcriptome analysis of ovarian tissue derived from a yellow eel, a prepubertal silver eel and a post-spawning matured eel. Two key players in steroidogenesis were strongly correlated with advanced sexual maturation, namely P450c17 and liver receptor homolog-1, suggesting that blood plasma steroids might qualify as minimally invasive markers for early detection of responders. Since the predictive value of plasma sex steroid levels for final maturation of the European eel had not yet been carefully examined, we performed an extensive artificial maturation trial. Farmed silver eels were treated with pituitary extracts and sampled at multiple time intervals. Expression of steroidogenesis-related genes in ovarian tissue of responding and non-responding eels after four weekly injections with pituitary extract was compared using a custom-built microarray and RNAseq. Increased expression of 17β-hsd1 was strongly linked to sexual maturation. Blood plasma levels of sex steroids were measured using ELISAs. We show that a 2.5-fold increase in blood-plasma estradiol level after 4 weekly pituitary extract injections is a strong predictor of final sexual maturation of female European eel.
AB - Complete sexual maturation of European eels (Anguilla anguilla) in captivity can only be achieved via injections with gonadotropins. For female eels this procedure takes 4-6. months and the response ranges from "unresponsive" to final maturation and ovulation. Reproductive success could be significantly increased via early selection of responders based on predictive markers and minimally invasive sampling methods. To get a better understanding of the genetic background of ovarian maturation of the European eel we performed a pilot deep-sequencing transcriptome analysis of ovarian tissue derived from a yellow eel, a prepubertal silver eel and a post-spawning matured eel. Two key players in steroidogenesis were strongly correlated with advanced sexual maturation, namely P450c17 and liver receptor homolog-1, suggesting that blood plasma steroids might qualify as minimally invasive markers for early detection of responders. Since the predictive value of plasma sex steroid levels for final maturation of the European eel had not yet been carefully examined, we performed an extensive artificial maturation trial. Farmed silver eels were treated with pituitary extracts and sampled at multiple time intervals. Expression of steroidogenesis-related genes in ovarian tissue of responding and non-responding eels after four weekly injections with pituitary extract was compared using a custom-built microarray and RNAseq. Increased expression of 17β-hsd1 was strongly linked to sexual maturation. Blood plasma levels of sex steroids were measured using ELISAs. We show that a 2.5-fold increase in blood-plasma estradiol level after 4 weekly pituitary extract injections is a strong predictor of final sexual maturation of female European eel.
KW - Artificial maturation
KW - European eel
KW - Minimally invasive
KW - Predictive markers
KW - Steroidogenesis
KW - Transcriptome profiling
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U2 - 10.1016/j.ygcen.2015.08.006
DO - 10.1016/j.ygcen.2015.08.006
M3 - Article
C2 - 26255685
AN - SCOPUS:84949624522
VL - 225
SP - 185
EP - 196
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
SN - 0016-6480
ER -