Molecular Cloning and Functional Characterization of Three 5-HT Receptor Genes (HTR1B, HTR1E, and HTR1F) in Chickens

Abstract

The serotonin (5-hydroxytryptamine, 5-HT) signaling system is involved in a variety of physiological functions, including the control of cognition, reward, learning, memory, and vasoconstriction in vertebrates. Contrary to the extensive studies in the mammalian system, little is known about the molecular characteristics of the avian serotonin signaling network. In this study, we cloned and characterized the full-length cDNA of three serotonin receptor genes (HTR1B, HTR1E and HTR1F) in chicken pituitaries. Synteny analyses indicated that HTR1B, HTR1E and HTR1F were highly conserved across vertebrates. Cell-based luciferase reporter assays showed that the three chicken HTRs were functional, capable of binding their natural ligands (5-HT) or selective agonists (CP94253, BRL54443, and LY344864) and inhibiting intracellular cAMP production in a dose-dependent manner. Moreover, activation of these receptors could stimulate the MAPK/ERK signaling cascade. Quantitative real-time PCR analyses revealed that HTR1B, HTR1E and HTR1F were primarily expressed in various brain regions and the pituitary. In cultured chicken pituitary cells, we found that LY344864 could significantly inhibit the secretion of PRL stimulated by vasoactive intestinal peptide (VIP) or forskolin, revealing that HTR1F might be involved in the release of prolactin in chicken. Our findings provide insights into the molecular mechanism and facilitate a better understanding of the serotonergic modulation via HTR1B, HTR1E and HTR1F in avian species.

Genome-Wide Association Study of Adhesive Capsulitis Suggests Significant Genetic Risk Factors

“…This locus is located 270 Kb away from POU1F1 and 212 Kb away from HTR1F . POU1F1 has been associated with the pituitary gland and generation of human growth hormone 25 , and HTR1F is a serotonin receptor with limited known biological roles 26 . Analysis of ATAC-Seq (Assay for Transposase-Accessible Chromatin using Sequencing) data available within the NCBI Genome Data Viewer did not suggest that this locus was highly regulatory or open.…”

Characterization of relaxin 3 and its receptors in chicken: Evidence for relaxin 3 acting as a novel pituitary hormone

“…In the present study, the high abundance of cRLN3 in the chicken pituitary led us to further investigate its distribution in pituitary cell clusters from a single-cell dataset reported by our research group (Zhang et al, 2021). As shown in Figure 6D, cRLN3 has been found mainly to localize in the gonadotroph cell clusters of female chickens.…”

“…In the present study, the high abundance of cRLN3 mRNA in the pituitary gland of female chickens led us to further investigate its expression regulation profile. Since cRLN3 was detected to be localized mainly in the gonadotroph cells, where the GnRHRs and CRHRs were found to be abundantly expressed (Shimizu and Bédécarrats, 2006;Joseph et al, 2009;Zhang et al, 2021), the hypothalamic factors GnRH and CART were employed to investigate their roles in the regulation of cRLN3 mRNA expression by qPCR. As shown in Figure 7A, the GnRH (10 nM) was able to slightly increase the expression of cRLN3 mRNA after 4 h of treatment.…”

Localized variation in ancestral admixture identifies pilocytic astrocytoma risk loci among Latino children

“…For example, the MAPK signaling gene program identified by Reitman et al [ 30 ] included CCDC144B, and LYZL1 (rs959431, rs555108, rs550240), one of the top genes we identified, is also reported by STRING [ 31 ] to interact with multiple members of the CCDC family including CCDC42 and CCDC73. The activation of HTR1E (rs74559531) has been reported to stimulate the MAPK/ERK signaling cascade [ 32 ]. NT5E (rs4707205) was shown to be a direct binder of miR-193b, an miRNA involved in the MAPK pathway [ 33 ].…”