Cloning and functional analysis of c/ebpα as negative regulator of dmrt1 in Chinese tongue sole (Cynoglossus semilaevis)

c/ebp alpha is a member of the C/EBP family of transcription factors, which are involved in cell growth and differentiation and have a conserved basic leucine zipper (bZIP) domain. However, little is known about its function in sex determination and differentiation. In the present study, c/ebp alpha was cloned from the gonads of Chinese tongue sole (Cynoglossus semilaevis). The full-length cDNA of c/ebp alpha was 1583 bp, with a 198-bp 5' UTR, a 446-bp 3' UTR, and a 939-bp open reading frame encoding a 312-amino acid peptide. qRT-PCR revealed that c/ebp alpha was predominantly expressed in undifferentiated gonads of male C. semilaevis at 30 dpf and 60 dpf and peaked at 60 dpf. Expression levels of c/ebp alpha in the testis were constantly higher than those in ovaries at all developmental stages. Moreover, a dual-luciferase assay revealed that c/ebp alpha could negatively regulate the male-determining gene dmrt1 in vitro. These results provide fundamental information indicating that C. semilaevis c/ebp alpha might be involved in early gonadal differentiation and functions as a negative regulator of dmrt1 by repressing its transcription.

Automated summary

The study showed that c/ebp alpha is highly expressed in the gonads of Chinese tongue sole and plays a crucial negative regulatory role in early gonadal differentiation during the juvenile period. Additionally, c/ebp alpha was found to negatively regulate the male-determining gene dmrt1 in vitro.