Wenxiu RU,Liushuai HUA,Yufeng WEI,et al.The Effect of the Cyp19a1 Gene Methylation Modification on Temperature-dependent Sex Determination of Reeves’ Turtle (Mauremys reevesii)[J].Asian Herpetological Reserch(AHR),2017,8(3):213-220.[doi:10.16373/j.cnki.ahr.170021]
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The Effect of the Cyp19a1 Gene Methylation Modification on Temperature-dependent Sex Determination of Reeves’ Turtle (Mauremys reevesii)
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Asian Herpetological Research[ISSN:2095-0357/CN:51-1735/Q]

2017 VoI.8 No.3
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The Effect of the Cyp19a1 Gene Methylation Modification on Temperature-dependent Sex Determination of Reeves’ Turtle (Mauremys reevesii)
Wenxiu RU1 2** Liushuai HUA2 3** Yufeng WEI2 Weiye LI2 Dainan CAO2 Yan GE2 Hong CHEN1 Xianyong LAN1* and Shiping GONG2*
1 Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling 712100, Shaanxi, China
2 Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangzhou 510260, China
3 Henan Key Laboratory of Farm Animal Breeding and Nutritional Regulation, Institute of Animal Husbandry and Veterinary Science, Henan Academy of Agricultural Sciences, Zhengzhou 450002, Henan, China
Reeves’ turtle Mauremys reevesii temperature-dependent sex determination (TSD) cyp19a1 gene methylation
Temperature-dependent sex determination (TSD) is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however, the molecular mechanisms governing this process remain unknown. Aromatase, encoded by the cyp19a1 gene, which converts androgens into estrogens in animals, was considered to be the key gene for TSD. In this study, the 5’-flanking region of the cyp19a1 gene in Reeves’ turtle (Mauremys reevesii) was cloned, and the promoter region was identified using the luciferase reporter assay. Then the eggs of Reeves’ turtle were incubated at different temperatures (26°C: male-biased temperature; 29°C: non-sex-biased temperature and 32°C: female-biased temperature). During the thermosensitive period, the adrenal kidney gonad complexes (AKG) were sampled. DNA methylation analysis of the AKG samples showed that the promoter region of the cyp19a1 gene was significantly de-methylated in the female-biased temperature regime (P<0.01). Quantitative analysis of the cyp19a1 gene and estrogen by qPCR and Elisa assay showed that the expression level of the cyp19a1 gene and estrogen content were both upregulated significantly at the female-biased temperature (P<0.01). These results indicated that the de-methylation response of the cyp19a1 gene to incubation temperature, especially at the female-biased temperature, could lead to temperature-specific expression of aromatase and increased estrogen levels, which may further determine gonadal development in Reeves’ turtle. These findings provide insights into the genetic mechanisms underlying TSD.


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Last Update: 2017-09-25