Small-scale transcriptomics reveals differences among gonadal stages in Asian seabass (Lates calcarifer)

Reproductive Biology and Endocrinology

Research

Junhui Jiang¹  László Orbán²  Preethi Ravi³  Woei Chang Liew⁴ 

[1] Reproductive Genomics Group, Temasek Life Sciences Laboratory, 1 Research Link National University of Singapore, 117604, Singapore, Singapore;Department of Biological Sciences, National University of Singapore, 21 Lower Kent Ridge Rd, 119077, Singapore, Singapore;Agri-Food and Veterinary Authority of Singapore, 5 Maxwell Rd, 069110, Singapore, Singapore;Reproductive Genomics Group, Temasek Life Sciences Laboratory, 1 Research Link National University of Singapore, 117604, Singapore, Singapore;Department of Biological Sciences, National University of Singapore, 21 Lower Kent Ridge Rd, 119077, Singapore, Singapore;Department of Animal Sciences and Animal Husbandry, Georgikon Faculty, University of Pannonia, H-8360, Keszthely, Hungary;Reproductive Genomics Group, Temasek Life Sciences Laboratory, 1 Research Link National University of Singapore, 117604, Singapore, Singapore;National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK, Bellary Road, 560065, Bangalore, India;Reproductive Genomics Group, Temasek Life Sciences Laboratory, 1 Research Link National University of Singapore, 117604, Singapore, Singapore;School of Biological Sciences, Nanyang Technological University, 50 Nanyang Ave, 639798, Singapore, Singapore;

关键词: qPCR;    Barramundi;    Maturation;    Sex;    Gene expression;   

DOI  :  10.1186/1477-7827-12-5

 received in 2013-08-29, accepted in 2013-12-25,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundThe Asian seabass (Lates calcarifer) is a protandrous hermaphrodite that typically matures as a male at approximately 2–4 years of age and then changes sex in subsequent years. Although several sexual maturation stages have been described histologically for both testis and ovary, the underlying gene expression profiles remain lacking. The development of a gene expression platform is therefore necessary to improve our understanding of the gonad development of this cultured teleost species.MethodsThirty Asian seabass gonads were collected from farms in Singapore, examined histologically and staged according to their sex and gonadal maturation status. Partial coding sequences of 24 sex-related genes were cloned using degenerate primers and were sequenced. Additional 13 cDNA sequences were obtained through next-generation sequencing. A real-time qPCR was then performed using the microfluidic-based Fluidigm 48.48 Dynamic arrays.ResultsWe obtained 17 ovaries and 13 testes at various stages of sexual maturation. Of the 37 genes that were tested, 32 (86%) showed sexually dimorphic expression. These genes included sex-related genes, sox9, wt1, amh, nr5a2, dmrt1 and nr0b1, which showed testis-enhanced expression similar to other vertebrate species. Known male- and female-enhanced germ cells markers, which were established from studies in other species, similarly showed testis- and ovary-enhanced expression, respectively, in the Asian seabass. Three pro-Wnt signaling genes were also upregulated in the ovary, consistent with existing studies that suggested the role of Wnt signaling in ovarian differentiation in teleosts and mammals. The expression patterns of genes involved in steroidogenesis, retinoic acid metabolism, apoptosis and NF-κB signaling were also described. We were able to classify gonads according to sex and gonadal maturation stages, based on their small-scale transcriptomic profiles, and to uncover a wide variation in expression profiles among individuals of the same sex.ConclusionsThe analysis of a selected set of genes related to reproduction and in sufficient number of individuals using a qPCR array can elucidate new insights into the molecular mechanisms involved in Asian seabass gonad development. Given the conservation of gene expression patterns found in this study, these insights may also help us draw parallels with other teleosts.

【 授权许可】

Unknown   
© Ravi et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.