GFP expression pattern in pituitary and gonads under the control of nuclear progesterone receptor promoter in transgenic zebrafish

Abstract

Background: The nuclear progesterone receptor (Pgr) is a ligand-dependent transcription factor primarily responsible for mediating progesterone actions relevant for reproduction across vertebrates. Information on the cellular localization of Pgr expression in the reproductive system is required for developing a comprehensive approach to elucidate the role of Pgr in reproduction. Results: We generated transgenic zebrafish Tg(pgr:eGFP) that express enhanced green fluorescent protein (eGFP) driven by promoter sequence of pgr gene. The tissue distribution pattern of egfp mRNA is consistent with the pgr mRNA expression in Tg(pgr:eGFP). In the pituitary, GFP signals are found in the proximal pars distalis. In order to better discern the cellular localization of GFP signals in gonads, Tg(pgr:eGFP) line was crossed with Tg(gsdf:nfsB-mCherry) line, specifically expressing nitroreductase-mCherry fusion protein in granulosa and Sertoli cells in ovary and testis, respectively. Imaging of testis tissue showed that GFP expression was confined to Leydig cells. In the ovary, GFP expression colocalized with the mCherry signal in granulosa cells. Intriguingly, we also identified some non-granulosa cells close to where blood vessels branched, expressing stronger GFP signals than granulosa cells. Conclusions: Analyzing Tg(pgr:eGFP) expression in zebrafish provided leads toward new routes to study the role of Pgr in reproduction.

Transcriptomic and Chromatin Landscape Analysis Reveals That Involvement of Pituitary Level Transcription Factors Modulate Incubation Behaviors of Magang Geese

“…Progesterone plays critical roles in reproduction across vertebrates. Nuclear PGR is a ligand-dependent transcription factor responsible for mediating progesterone action related to reproduction [ 72 ]. Our results indicated that closed DARs related to the transcriptional activity of NRs, which sense change among androgen, glucocorticoid, and progesterone in the pituitary.…”

Identifying the Interaction of the Brain and the Pituitary in Social – and Reproductive – State of Tilapia by Transcriptome Analyses

“…As a female sex hormone mainly regulates gonadal development, little is known regarding the direct regulation of progesterone on gonadotrophs in male fish. The only evidence is the expression of the re- ceptor in the pituitary of zebrafish [105], and that pgr knockout in tilapia males causes a decrease in gonadal size and fshβ expression in the pituitary [106]. In dispersed cells from pituitaries of female tilapia, higher doses of 17α,20β-dihydroxy-4-pregnen-3-one (DHP) increased the expression of GnRH receptors, dopamine receptors (DRD2), and gonadotrophins in a dose-dependent manner [96].…”