TY - JOUR
T1 - Expression changes of mRNAs encoding kisspeptins and their receptors and gonadotropin-releasing hormones during early development and gonadal sex differentiation periods in the brain of chub mackerel (Scomber japonicus)
AU - Selvaraj, Sethu
AU - Kitano, Hajime
AU - Ohga, Hirofumi
AU - Yamaguchi, Akihiko
AU - Matsuyama, Michiya
N1 - Funding Information:
This research was funded by a Grant-in-Aid for Scientific research from the Japan Society for the Promotion of Science (JSPS) to M.M. A part of the research data was derived from a presentation made at International Congress on Comparative Endocrinology (ICCE 2013) meeting. The first author S.S. is supported by the JSPS postdoctoral fellowship ( PU13010 ). The authors declare that they have no competing interests.
Publisher Copyright:
© 2014 Elsevier Inc.
PY - 2015/10/1
Y1 - 2015/10/1
N2 - In recent years, brain kisspeptin system has been shown to be involved in diverse reproductive function, including sexual differentiation in vertebrates. Our previous reports demonstrated that the chub mackerel (Scomber japonicus) brain expresses two kisspeptin (kiss1, kiss2), two kisspeptin receptor (kissr1, kissr2) and three gonadotropin-releasing hormone (gnrh1, gnrh2, gnrh3) genes. In the present study, using quantitative real-time PCR (qRT-PCR) assays, we analysed expression changes of these genes during early development (0-30 dphs) and gonadal sex differentiation periods (37-60 dphs). Absolute expression level of kiss-kissr-gnrh in the whole head was higher between 0 and 15 dphs, in comparison to later developmental periods. Histological analyses revealed presence of sexually differentiated males and females with testicular and ovarian features at 37, 45, and 60 dphs. In both males and females, kiss2, kissr1, and kissr2 levels were higher at 37 dph, in comparison to 45 and 60 dphs, with kiss1 showing no significant differences. Levels of all three gnrh mRNAs were higher at 45 dph, in comparison to 60 dph. Changes in the expression level of kiss-kissr-gnrh mRNAs in different brain regions of sexually differentiated males and females indicated differences in their regional distribution. These results suggest possible involvement of Kiss-KissR-GnRH systems during early development and gonadal sex differentiation in the chub mackerel.
AB - In recent years, brain kisspeptin system has been shown to be involved in diverse reproductive function, including sexual differentiation in vertebrates. Our previous reports demonstrated that the chub mackerel (Scomber japonicus) brain expresses two kisspeptin (kiss1, kiss2), two kisspeptin receptor (kissr1, kissr2) and three gonadotropin-releasing hormone (gnrh1, gnrh2, gnrh3) genes. In the present study, using quantitative real-time PCR (qRT-PCR) assays, we analysed expression changes of these genes during early development (0-30 dphs) and gonadal sex differentiation periods (37-60 dphs). Absolute expression level of kiss-kissr-gnrh in the whole head was higher between 0 and 15 dphs, in comparison to later developmental periods. Histological analyses revealed presence of sexually differentiated males and females with testicular and ovarian features at 37, 45, and 60 dphs. In both males and females, kiss2, kissr1, and kissr2 levels were higher at 37 dph, in comparison to 45 and 60 dphs, with kiss1 showing no significant differences. Levels of all three gnrh mRNAs were higher at 45 dph, in comparison to 60 dph. Changes in the expression level of kiss-kissr-gnrh mRNAs in different brain regions of sexually differentiated males and females indicated differences in their regional distribution. These results suggest possible involvement of Kiss-KissR-GnRH systems during early development and gonadal sex differentiation in the chub mackerel.
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U2 - 10.1016/j.ygcen.2014.09.019
DO - 10.1016/j.ygcen.2014.09.019
M3 - Article
C2 - 25304825
AN - SCOPUS:84949623511
VL - 222
SP - 20
EP - 32
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
SN - 0016-6480
ER -