Potential Involvement of Gene in Ovarian Development of Chinese Tongue Sole, .

Ewsr1 encodes a protein that acts as a multifunctional molecule in a variety of cellular processes. The full-length of and were cloned in Chinese tongue sole (). The open reading frame (ORF) of was 1,767 bp that encoded 589 amino acids, while was 1,794 bp that encoded 598 amino acids. Real-time PCR assays showed that exhibited significant female-biased expression and could be hardly detected in male. It has the most abundant expression in ovaries among eight healthy tissues. Its expression in ovary increased gradually from 90 d to 3 y with ovarian development and reached the peak at 3 y. After knockdown with siRNA interference, several genes related to gonadal development including , and were down-regulated in ovarian cell line, suggesting the possible participation of in ovarian development. The dual-luciferase reporter assay revealed that the -733/-154 bp promoter fragment exhibited strong transcription activity human embryonic kidney (HEK) 293T cell line. The mutation of a MAF BZIP Transcription Factor K (Mafk) binding site located in this fragment suggested that transcription factor Mafk might play an important role in basal transcription. Our results will provide clues on the gene expression level, transcriptional regulation and knock-down effect of gene during ovarian development in teleost.