Prolactin Receptor Gene Research Articles

Early and late feathering in turkey and chicken: same gene but different mutations

BackgroundSex-linked slow (SF) and fast (FF) feathering rates at hatch have been widely used in poultry breeding for autosexing at hatch. In chicken, the sex-linked K (SF) and k+ (FF) alleles are responsible for the feathering rate phenotype. Allele K is dominant and a partial duplication of the prolactin receptor gene has been identified as the causal mutation. Interestingly, some domesticated turkey lines exhibit similar slow- and fast-feathering phenotypes, but the underlying genetic components and causal mutation have never been investigated. In this study, our aim was to investigate the molecular basis of feathering rate at hatch in domestic turkey.ResultsWe performed a sequence-based case–control association study and detected a genomic region on chromosome Z, which is statistically associated with rate of feathering at hatch in turkey. We identified a 5-bp frameshift deletion in the prolactin receptor (PRLR) gene that is responsible for slow feathering at hatch. All female cases (SF turkeys) were hemizygous for this deletion, while 188 controls (FF turkeys) were hemizygous or homozygous for the reference allele. This frameshift mutation introduces a premature stop codon and six novel amino acids (AA), which results in a truncated PRLR protein that lacks 98 C-terminal AA.ConclusionsWe present the causal mutation for feathering rate in turkey that causes a partial C-terminal loss of the prolactin receptor, and this truncated PRLR protein is strikingly similar to the protein encoded by the slow feathering K allele in chicken.

Investigating of Polymorphism in Intron 1 of Prolactin Receptor Gene in Shal Breed and Shal×Romanov Crossbreed using PCR-SSCP Technique

Investigating of Polymorphism in Intron 1 of Prolactin Receptor Gene in Shal Breed and Shal×Romanov Crossbreed using PCR-SSCP Technique

Prolactin improves hepatic steatosis via CD36 pathway

Prolactin (PRL) is a multifunctional polypeptide with effects on metabolism, however, little is known about its effect on hepatic steatosis and lipid metabolism. Herein, we aimed to assess the role of PRL in the development of non-alcoholic fatty liver disease (NAFLD). The serum PRL levels of 456 patients with NAFLD, 403 controls without NAFLD diagnosed by ultrasound, and 85 individuals with liver histology obtained during metabolic surgery (44 female and 30 male patients with NAFLD and 11 age-matched non-NAFLD female individuals) were evaluated. The expression of the gene encoding the prolactin receptor (PRLR) and signalling molecules involved in hepatic lipid metabolism were evaluated in human liver and HepG2 cells. The effects of overexpression of PRLR or fatty acid translocase (FAT)/CD36 or knockdown of PRLR on hepatic lipid metabolism were tested in free fatty acid (FFA)-treated HepG2 cells. Circulating PRL levels were lower in individuals with ultrasound-diagnosed NAFLD (men: 7.9 [range, 5.9-10.3] µg/L; women: 8.7 [range, 6.1-12.4] µg/L) than those with non-NAFLD (men: 9.1 [range, 6.8-13.0] µg/L, p = 0.002; women: 11.6 [range, 8.2-16.1] µg/L, p <0.001). PRL levels in patients with biopsy-proven severe hepatic steatosis were lower compared with those with mild-to-moderate hepatic steatosis in both men (8.3 [range, 5.4-9.5] µg/L vs. 9.7 [range, 7.1-12.3] µg/L, p = 0.031) and women (8.5 [range, 4.2-10.6] µg/L vs. 9.8 [range, 8.2-15.7] µg/L, p = 0.027). Furthermore, hepatic PRLR gene expression was significantly reduced in patients with NAFLD and negatively correlated with CD36 gene expression. In FFA-induced HepG2 cells, PRL treatment or PRLR overexpression significantly reduced the expression of CD36 and lipid content, effects that were abrogated after silencing of PRLR. Furthermore, overexpression of CD36 significantly reduced the PRL-mediated improvement in lipid content. Our results reveal a novel association between the central nervous system and the liver, whereby PRL/PRLR improved hepatic lipid accumulation via the CD36 pathway. Our clinical study suggests a negative association between prolactin (PRL)/prolactin receptor (PRLR) and the presence of non-alcoholic fatty liver disease (NAFLD). Using cell experiments, we found that PRL ameliorates hepatic steatosis via the hepatic PRLR and fatty acid translocase (FAT)/CD36, a key transporter of free fatty acid uptake in liver. Our findings suggest a novel approach to improving NAFLD using PRL and PRLR. Clinical trial number: NCT03296605.

Investigation of Polymorphism in Exon 2 of Prolactin Receptor Gene in Japanese Quail and Guinea Fowl

Investigation of Polymorphism in Exon 2 of Prolactin Receptor Gene in Japanese Quail and Guinea Fowl

Prolactin receptor gene polymorphism and the risk of recurrent pregnancy loss: a case-control study

Since the first study was published reporting the candidate association between the prolactin receptor gene intron C/T polymorphism (rs37389) and recurrent miscarriage, no replication study has been performed. In this study, we investigated the role of the prolactin receptor gene C/T polymorphism in 311 Korean women with recurrent pregnancy loss and 314 controls. Genotyping for prolactin receptor gene intron C/T polymorphism was performed using a TaqMan assay. The significance of difference in the genotype distribution was assessed using a chi-square test, and continuous variables were compared using a Student’s t-test. The genotype distribution of the prolactin receptor gene C/T polymorphism in the recurrent pregnancy loss group did not differ from that in the control group (CC/CT/TT rates were 49.8%/41.5%/8.7% and 52.5%/37.6%/9.9% for the recurrent pregnancy loss patient and control groups, respectively, p = .587). When the analysis was restricted to patients with three or more consecutive spontaneous miscarriages or patients without prior live birth, there were also no differences in the genotype distribution between these subgroups and controls. In conclusion, the findings of the current study suggest that the prolactin receptor gene intron C/T polymorphism is not a major determinant of the development of recurrent pregnancy loss.Impact statementWhat is already known: Many studies have investigated whether there is a genetic component for the risk of recurrent pregnancy loss. Recently, one study investigated whether genetic polymorphisms involved in the regulation of the hypothalamic-pituitary-ovarian axis would be associated with recurrent miscarriage. Among 35 polymorphisms in 20 candidate genes, genotype distribution with regard to the prolactin receptor gene intron C/T polymorphism (rs37389) differed between the recurrent miscarriage and the control groups. Since this study reporting the candidate association between the prolactin receptor gene and recurrent miscarriage, no replication study has been performed.What the results of this study add: The genotype distribution of the prolactin receptor gene C/T polymorphism in the recurrent miscarriage group did not differ from that in the control group.What the implications are of these findings: Our study may be useful in that it is the first replication study since the initial report of the association of prolactin receptor gene polymorphism with recurrent miscarriage. Although no association was found, the potential role of prolactin in pregnancy loss needs to be further investigated because prolactin and its receptor have been postulated to play an important role in the maintenance of normal pregnancy.

Prolactin receptors in Rip-cre cells, but not in AgRP neurones, are involved in energy homeostasis.

Among its many functions, prolactin has been implicated in energy homeostasis, particularly during pregnancy and lactation. The arcuate nucleus is a key site in the regulation of energy balance. The present study aimed to examine whether arcuate nucleus neuronal populations involved in energy homeostasis are prolactin responsive and whether they can mediate the effects of prolactin on energy homeostasis. To determine whether Agrp neurones or Rip-Cre neurones are prolactin responsive, transgenic mice expressing the reporter td-tomato in Agrp neurones (td-tomato/Agrp-Cre) or Rip-Cre neurones (td-tomato/Rip-Cre) were treated with prolactin and perfused 45minutes later. Brains were processed for double-labelled immunohistochemistry for pSTAT5, a marker of prolactin-induced intracellular signalling, and td-tomato. In addition, Agrp-Cre mice and Rip-Cre mice were crossed with mice in which the prolactin receptor gene (Prlr) was flanked with LoxP sites (Prlrlox/lox mice). The Prlrlox/lox construct was designed such that Cre-mediated recombination resulted in deletion of the Prlr and expression of green fluorescent protein (GFP) in its place. In td-tomato/Rip-Cre mice, prolactin-induced pSTAT5 was co-localised with td-tomato, indicating that there is a subpopulation of Rip-Cre neurones in the arcuate nucleus that respond to prolactin. Furthermore, mice with a specific deletion of Prlr in Rip-Cre neurones had lower body weights, increased oxygen consumption, increased running wheel activity and numerous cells in the arcuate nucleus had positive GFP staining indicating deletion of Prlr from Rip-Cre neurones. By contrast, no co-localisation of td-tomato and pSTAT5 was observed in td-tomato/Agrp-Cre mice after prolactin treatment. Moreover, Prlrlox/lox /Agrp-Cre mice had no positive GFP staining in the arcuate nucleus and did not differ in body weight compared to littermate controls. Overall, these results indicate that Rip-Cre neurones in the arcuate nucleus are responsive to prolactin and may play a role in the orexigenic effects of prolactin, whereas prolactin does not directly affect Agrp neurones.

Interlaboratory validation of a real-time PCR detection method for bovine- and ovine-derived material

In this work we performed interlaboratory validation of a Taqman real-time PCR method for the identification of bovine and ovine material. The Bos taurus beta-actin gene (ACTB) and Ovis aries prolactin receptor gene (PRLR) were selected as the bovine and ovine species-specific amplifying target sequences, and primers and TaqMan probes were designed accordingly. The precision, efficiency, false positive rate, limit of detection (LOD95%) and probability of detection (POD) were determined, and the results demonstrated that both bovine and ovine detection methods performed well. The high homogeneity of the results indicates that the detection methods are suitable for a wide range of applications, and the tools developed herein could be applied by official and third-party detection institution to maintain quality in the food and feedstuff industries.

Study of Prolactin Receptor Gene (PRLR5) polymorphisms and its association with egg production in Kadaknath hens

The present study was conducted to investigate the polymorphisms of prolactin receptor (PRLR5) gene and its association with egg production in Kadaknath hens. Egg production is a polygenic inheritance trait. Study was conducted on twenty female birds of Kadaknath kept for laying. Egg production performances were recorded as age at first laying (AFE), Body Weight at First Egg (WFE), Mean Egg Weight (MEW) and Total No. of Eggs at 90 days of laying (TEN). Genomic DNA isolated from 2- 3 of blood collected from wing vein of each bird was amplified for prolactin receptor (PRLR5) gene with specific primer by standardizing and optimising the PCR protocols. PCR was performed in a final volume of 20 ml. The amplified PCR products were resolved on the gels to generate polymorphisms. PRLR5 was digested with BamHI. Retriction digested products were run on 2% agarose gel electrophoresis. PRLR5 showed two alleles and two genotypes. The frequency of AA genotype at this locus was 0.75 and BB genotype was 0.25. The AFE (d), WFE (Kg), MEW (g) and TEN of Kadaknath hens in the present study were found to be 188.000.71, 1.260.03, 42.830.21 and 37.750.59 respectively. Birds with AA genotype of PRLR5 had a significantly (P less than 0.05) better WFE and AFE than BB genotype. Prolactin receptor (PRLR5) genes produced polymorphism in Kadaknath and were associated with egg production traits.

Association of polymorphic variants in MSTN, PRL, and DRD2 genes with intensity of young animal growth in Pushkin breed chickens

Polymorphic variants in the myostatin, prolactin, and D2 dopamine receptor genes were analyzed in Pushkin breed chickens (n = 231). The rs313744840 single nucleotide polymorphism was studied in the myostatin gene by means of the PCR–RFLP method. The cocks with different genotypes did not differ from each other by the live weight. Chickens with AA genotype were found to be significantly larger than their coevals with AG and GG genotypes at the age of 49 days (P < 0.01). Polymorphism based on the insertion–deletion of a small gene region (indel-polymorphism) was considered in the prolactin and D2 dopamine receptor genes. Differences by the prolactin gene were observed at 7 days of age. The cocks homozygous by the DD deletion were significantly larger than heterozygous ID coevals (P < 0.05). The II cocks significantly differed by the D2 dopamine receptor gene from heterozygous ID coevals by the live weight at 49 and 110 days. In chickens, II homozygotes by the mutation in the D2 dopamine receptor gene were larger than coevals at 7 days, while they had a lower live weight at 110 days (P < 0.05).

Prolactin Upregulates Female-Predominant P450 Gene Expressions and Downregulates Male-Predominant Gene Expressions in Mouse Liver.

Prolactin is a polypeptide hormone with over 300 separate biologic activities. Its serum level is increased during pregnancy and lactation, and it has been reported that pregnancy and lactation affect drug and steroid metabolism in mice and humans. Several studies reported that pregnancy or lactation influences liver cytochrome P450 (P450) expression and its activity, affecting the biosynthesis of steroids and xenobiotics through growth hormone or sex hormones; however, the role of prolactin as the regulator of liver P450 expression has not been elucidated so far. In the present study, we focused on prolactin as the regulator of expression of liver sex-predominant genes, including P450s. To investigate the role of prolactin in the hepatic gene expressions, pCAGGS expression vector containing mouse prolactin cDNA was transfected by hydrodynamic injection into both male and female mice. Hyperprolactinemia phosphorylated signal transducer and activator of transcription 5 in the liver and augmented female mouse liver mRNA expression of Cyp3a16, Cyp3a41, Cyp3a44, Cyp2b9, and prolactin receptor genes, whose expressions were female-predominant in hepatocytes. Moreover, liver expression of male-predominant genes such as Cyp2d9, Cyp7b1, Mup1, and Alas2 were reduced in male mice with hyperprolactinemia. The serum levels of conventional regulators of hepatic gene expressions, growth hormone, and testosterone were not affected by hyperprolactinemia. We demonstrated that prolactin upregulated female-predominant genes in female mice and downregulated male-predominant genes in male mice. We conjecture that higher concentration of prolactin would alter steroid and xenobiotic metabolisms by modulating hepatic P450 gene expressions during pregnancy and lactation.

Associations of polymorphisms in the prolactin receptor gene with growth trait in Japanese quail (Coturnix coturnix japonica)

Prolactin receptor (PRLR), as an important regulatory gene about growth and differentiation, might be a condition gene for reproductive traits. The prolactin receptor is a specific receptor for prolactin (PRL), which is an anterior pituitary peptide hormone involved in various physiological activities and is essential for reproductive improvement. In chickens, the PRLR gene is on the Z chromosome. In the present study, the polymorphism of exon 2 of PRLR gene in Japanese Quail (Coturnix coturnix japonica) was investigated. Blood samples of 180 Japanese Quail were collected randomly. DNA was extracted from blood samples and amplified. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis of the exon 2 of PRLR gene. PCR-SSCP analysis of the exon 2 region revealed two banding patterns. Two different SSCP patterns, representing two different genotypes, were identified. The frequencies of the observed genotypes were 0.939 and 0.061 for AA and BB. Allele frequencies were 0.939 and 0.061 for A and B. Observed heterozygosity (Hobs) value was 0.0. The chi-square test showed significant (P&lt;0.05) deviation from Hardy-Weinberg equilibrium for this locus in studied population. The effect of these genotypes on weight gain was investigated, and the BB genotype was found to be associated with body weight at 46 days. This was the first study on polymorphism of PRLR gene in Japanese quail.

Genetic Polymorphism Study in Prolactin Receptor (PRLR) Gene and their Association with Milk Production Traits in Indian Cattle Breeds

Genetic Polymorphism Study in Prolactin Receptor (<i>PRLR</i>) Gene and their Association with Milk Production Traits in Indian Cattle Breeds

Association between prolactin receptor gene polymorphism (PRLR) with reproduction performance traits of Polish swine

The aim of this study was to estimate the relationship between prolactin receptor (PRLR) gene polymorphism and litter size in pigs of synthetic line 990 (n = 374). Prolactin receptor gene variants were determined by PCR–RFLP method. It was demonstrated that the analyzed polymorphism had significant influence (P ≤ 0.05) on reproduction traits in the first parity.

Two tagSNPs in the prolactin receptor gene are associated with growth and litter traits in Boer and Macheng Black crossbred goats

Boer and Macheng Black goat breeds were used to detect single-nucleotide polymorphisms (SNPs) in the gene for the prolactin receptor (PRLR) by DNA sequencing. Thirteen mutations (seven in the exon, four in the intron, and two in the 3′ UTR) were found. We performed comprehensive linkage disequilibrium (LD) and haplotype analyses of the 13 SNPs of PRLR and found that the SNPs were in two LD blocks in 300 F2 hybrids of Boer×Macheng Black goats. Analyses of the tag SNPs indicated that the g.184822G/A and g.185275C/T SNPs were significantly associated with growth traits, and individuals with the combinative genotype GGTT had the lowest levels of some growth traits. Moreover, Individuals with genotype GA had stronger offspring than did individuals with genotype GG at the g.184822G/A locus. This study revealed that PRLR is a promising candidate for the selection of both growth and litter traits in these goats.

Hormone Receptor Expression Analyses in Neoplastic and Non-Neoplastic Canine Mammary Tissue by a Bead Based Multiplex Branched DNA Assay: A Gene Expression Study in Fresh Frozen and Formalin-Fixed, Paraffin-Embedded Samples.

Immunohistochemistry (IHC) is currently considered the method of choice for steroid hormone receptor status evaluation in human breast cancer and, therefore, it is commonly utilized for assessing canine mammary tumors. In case of low hormone receptor expression, IHC is limited and thus is complemented by molecular analyses. In the present study, a multiplex bDNA assay was evaluated as a method for hormone receptor gene expression detection in canine mammary tissues. Estrogen receptor (ESR1), progesterone receptor (PGR), prolactin receptor (PRLR) and growth hormone receptor (GHR) gene expressions were evaluated in neoplastic and non-neoplastic canine mammary tissues. A set of 119 fresh frozen and 180 formalin-fixed, paraffin-embedded (FFPE) was comparatively analyzed and used for assay evaluation. Furthermore, a possible association between the hormone receptor expression in different histological subtypes of canine malignant mammary tumors and the castration status, breed and invasive growth of the tumor were analyzed. The multiplex bDNA assay proved to be more sensitive for fresh frozen specimens. Hormone receptor expression found was significantly decreased in malignant mammary tumors in comparison to non-neoplastic tissue and benign mammary tumors. Among the histological subtypes the lowest gene expression levels of ESR1, PGR and PRLR were found in solid, anaplastic and ductal carcinomas. In summary, the evaluation showed that the measurement of hormone receptors with the multiplex bDNA assay represents a practicable method for obtaining detailed quantitative information about gene expression in canine mammary tissue for future studies. Still, comparison with IHC or quantitative real-time PCR is needed for further validation of the present method.

Role of EGF/ERBB1 in the transcriptional regulation of the prolactin receptor independent of estrogen and prolactin in breast cancer cells.

Prolactin receptor (PRLR) and epidermal growth factor receptor (EGFR/ERBB1) have important roles in the physiology of the human breast and in the etiology and progression of breast cancer. Our present studies in MCF-7 cells revealed that EGF induces up-regulation of PRLR via activation of EGFR signalling pathways leading to activation of estrogen receptor α (ERα). EGF treatment of MCF-7 cells cultured in absence of estradiol induced expression of PRLR that was consistent with the activation of PRLR generic promoter (hPIII). These were abolished by ERα antagonist and siRNA, indicating involvement of ERα in EGF-induced hPIII promoter activity. MEK/MAPK and PI3K/AKT pathways participate in the phosphorylation of ERα induced by EGF/EGFR. PI3K and MEK inhibitors abolished EGF-induced PRLR promoter activity. Increased recruitment of non-DNA bound unliganded ERα to Sp1 and C/EBPβ bound to their sites at hPIII induced by EGF was abrogated by ERα siRNA demonstrating the requisite role of phospho-ERα in PRLR upregulation. EGF/EGFR, independent of endogenous prolactin induced phosphorylation of STAT5b with participation of c-SRC and recruitment of STAT5b:STAT5b to a GAS site at hPIII. STAT5b interaction with ERα was essential for stable phospho-ERα recruitment to the SP1/CEBPβ complex. These studies indicate a role for paracrine EGF via EGFR independent of estrogen and prolactin in the transcriptional activation of PRLR gene expression and its contribution to high levels of PRLRs in breast cancer. These by maximizing the actions of endogenous prolactin could have a role in cancer progression and resistance to endocrine therapy.

The Prolactin Receptor Gene Expression Variance in Marshes and Riverine Buffalos in Iraq

The Prolactin Receptor Gene Expression Variance in Marshes and Riverine Buffalos in Iraq

Prolactin Pro-Differentiation Pathway in Triple Negative Breast Cancer: Impact on Prognosis and Potential Therapy

Triple negative breast cancer (TNBC) is a heterogeneous disease associated with poor clinical outcome and lack of targeted therapy. Here we show that prolactin (PRL) and its signaling pathway serve as a sub-classifier and predictor of pro-differentiation therapy in TNBC. Using immunohistochemistry and various gene expression in silica analyses we observed that prolactin receptor (PRLR) protein and mRNA levels are down regulated in TNBC cases. In addition, examining correlation of PRLR gene expression with metagenes of TNBC subtypes (580 cases), we found that PRLR gene expression sub-classifies TNBC patients into a new subgroup (TNBC-PRLR) characterized by epithelial-luminal differentiation. Importantly, gene expression of PRL signaling pathway components individually (PRL, PRLR, Jak2 and Stat5a), or as a gene signature is able to predict TNBC patients with significantly better survival outcomes. As PRL hormone is a druggable target we determined the biological role of PRL in TNBC biology. Significantly, restoration/activation of PRL pathway in TNBC cells representative of mesenchymal or TNBC-PRLR subgroups led to induction of epithelial phenotype and suppression of tumorigenesis. Altogether, these results offer potential new modalities for TNBC stratification and development of personalized therapy based on PRL pathway activation.

Changes in the Expression of the Prolactin Receptor (PRLR) Gene in Different Physiological Stages in the Mammary Gland of the Iranian Adani Goat.

The actions of prolactin hormone are mediated by prolactin receptor (PRLR), and proliferation and differentiation of secretory mammary epithelium are dependent on the presence of its receptors. To understand the PRLR expression pattern in mammary gland of dairy goat during different lactation stages, in this study, we first estimated the milk yield breeding value by multitrait random regression model and then compared the expression of the gene in different physiological stage of mammary gland between high- and low-breeding value groups. We assayed the transcription level of the gene by quantitative real-time PCR method, and its outcomes were analysed by a statistical model containing breeding value groups, sampling times and their interactions as fixed effects. The results indicated that the expression levels of PRLR gene were significantly upregulated in the drying stage (p<0.01). The transcription pattern of the gene was significantly different between the two breeding value groups (p<0.01), so that the amount of PRLR mRNA was significantly higher in the low-breeding value groups of animals in the lactation stage (p<0.01). Based on the results of this study, it could be suggested that the abundance of PRLR transcripts in mammary gland of goat might be changed by some physiological, environmental and genetic factors. Nucleotide variations in the promoter region might be resulted in various transcription activities of the gene which should be studied in a complementary research.

The Eyes Have it! Protective Role of Prolactin in the Retina

The Eyes Have it! Protective Role of Prolactin in the Retina