Homeodomain Proteins SIX3 and SIX6 Regulate Gonadotrope-specific Genes During Pituitary Development.

Sine oculis-related homeobox 3 (SIX3) and SIX6, 2 closely related homeodomain transcription factors, are involved in development of the mammalian neuroendocrine system and mutations of Six6 adversely affect fertility in mice. We show that both small interfering RNA knockdown in gonadotrope cell lines and knockout of Six6 in both embryonic and adult male mice (Six6 knockout) support roles for SIX3 and SIX6 in transcriptional regulation in gonadotrope gene expression and that SIX3 and SIX6 can functionally compensate for each other. Six3 and Six6 expression patterns in gonadotrope cell lines reflect the timing of the expression of pituitary markers they regulate.

FOXO1 transcription factor inhibits luteinizing hormone β gene expression in pituitary gonadotrope cells.

Synthesis of luteinizing hormone (LH) is tightly controlled by a complex network of hormonal signaling pathways that can be modulated by metabolic cues, such as insulin. One group of candidate genes that may be regulated by insulin signaling in pituitary gonadotrope cells is the FOXO subfamily of forkhead transcription factors. In this study we investigated whether FOXO1 is expressed in gonadotropes and if it can modulate LH β-subunit (Lhb) gene expression.

RhinoVax is an efficient adjuvant in oral immunisation of young chickens and cholera toxin B is an effective oral primer in subcutaneous immunisation with Freund's incomplete adjuvant.

Forty-five approximately 50% in-bred 14-day-old White Leghorn female chickens (Gallus domesticus) originating from 11 hens were distributed into 5 treatment groups containing one sister in each treatment group. Phase I involved oral administration of an antigen, Bovine Serum Albumin (BSA), in combination with various adjuvant preparations, either Cholera Toxin B-subunit (CTB) and/or RhinoVax (RV). A positive control group received BSA emulsified in Freund's Incomplete Adjuvant (FIA) by subcutaneous injection.