A Transcriptomic Analysis of Gonads from the Low-Temperature-Induced Masculinization of Takifugu rubripes .

The phenotypic sex of fish is usually plastic. Low-temperature treatment induces the masculinization of Takifugu rubripes , resulting in pseudo-males (PM) with the physiological sex of a male (M) and genetic sex of a female (F). For a comparison of gonadal transcriptomes, we collected gonads from three groups of T. rubripes (F, M, and PM) for high-throughput transcriptome sequencing. The results provided 467,640,218 raw reads (70.15 Gb) and a total of 436,151,088 clean reads (65.43 Gb), with an average length of 150 bp. Only 79 differentially expressed genes (DEGs) were identified between F and PM, whereas 12,041 and 11,528 DEGs were identified between F and M, and PM and M, respectively. According to the functional annotation of DEGs, 13 DEGs related to gonadal development were screened ( LOC101066759 , dgat1 , limk1 , fbxl3 , col6a3 , fgfr3 , dusp22b , svil , abhd17b , srgap3 , tmem88b , bud4 , and mustn10 ) which might participate in formating PM. A quantitative PCR of the DEGs confirmed the reliability of the RNA-seq. Our results provide an important contribution to the genome sequence resources for T. rubripes and insight into the molecular mechanism of masculinization in a cultured fish subject to low-temperature treatment.