Transcript profiling of candidate genes in testis of pigs exhibiting large differences in androstenone levels

Abstract

BackgroundBoar taint is an unpleasant odor and flavor of the meat and occurs in a high proportion of uncastrated male pigs. Androstenone, a steroid produced in testis and acting as a sex pheromone regulating reproductive function in female pigs, is one of the main compounds responsible for boar taint. The primary goal of the present investigation was to determine the differential gene expression of selected candidate genes related to levels of androstenone in pigs.ResultsAltogether 2560 boars from the Norwegian Landrace and Duroc populations were included in this study. Testicle samples from the 192 boars with most extreme high or low levels of androstenone in fat were used for RNA extraction, and 15 candidate genes were selected and analyzed by real-competitive PCR analysis. The genes Cytochrome P450 c17 (CYP17A1), Steroidogenic acute regulatory protein (STAR), Aldo-keto reductase family 1 member C4 (AKR1C4), Short-chain dehydrogenase/reductase family member 4 (DHRS4), Ferritin light polypeptide (FTL), Sulfotransferase family 2A, dehydroepiandrosterone-preferring member 1 (SULT2A1), Cytochrome P450 subfamily XIA polypeptide 1 (CYP11A1), Cytochrome b5 (CYB5A), and 17-beta-Hydroxysteroid dehydrogenase IV (HSD17B4) were all found to be significantly (P < 0.05) up-regulated in high androstenone boars in both Duroc and Landrace. Furthermore, Cytochrome P450 c19A2 (CYP19A2) was down-regulated and progesterone receptor membrane component 1 (PGRMC1) was up-regulated in high-androstenone Duroc boars only, while CYP21 was significantly down-regulated (2.5) in high-androstenone Landrace only. The genes Nuclear Receptor co-activator 4 (NCOA4), Sphingomyrlin phosphodiesterase 1 (SMPD1) and 3β-hydroxysteroid dehydrogenase (HSD3B) were not significantly differentially expressed in any breeds. Additionally, association studies were performed for the genes with one or more detected SNPs. Association between SNP and androstenone level was observed in CYB5A only, suggesting cis-regulation of the differential transcription in this gene.ConclusionA large pig material of highly extreme androstenone levels is investigated. The current study contributes to the knowledge about which genes that is differentially expressed regard to the levels of androstenone in pigs. Results in this paper suggest that several genes are important in the regulation of androstenone level in boars and warrant further evaluation of the above mentioned candidate genes, including analyses in different breeds, identification of causal mutations and possible gene interactions.

A correlation study of Boar taint-related genes, Boar tant substances and sex hormones in Bama miniature pigs at defferent ages

“…These results were consistent with those of Grindflek's et. al (2010) study about Duroc and Landrace (Grindflek et al, 2010). In a similar study in 108 kg live weight, the level of plasma testosterone was 75.1 nM in wild pigs and 58.5 nM in Yorkshire pigs (Babol et al, 1999), which are greater than those of Bama pigs (7.13 ng/mL plasma testosterone at 12 months of age) in this study.…”

“…StAR has a key effect on limiting the rate of cholesterol metabolism and steroid hormone synthesis. As steroid hormone, StAR promotes the transitioning of cholesterol from the outer to the inner mitochondrial membrane as an in vivo steroidal substance (Ning et al, 2009a;Ning et al, 2009b), and StAR has an obvious positive correlation with androstenone phenotype (Grindflek et al, 2010). The effects of several transcription factor on the expression levels of several transcripts of the metabolism of androstenone and skatole have been tested (Gray and Squires, 2013a;Gray and Squires, 2013b), except for COUP-TF1.…”

Preliminary study of FMO1, FMO5, CYP21, ESR1, PLIN2 and SULT2A1 as candidate gene for compounds related to boar taint

“…ESR1 is located on SSC1p24-25 which is evidence of harbouring several QTL for sperm count and sperm motility (Ren et al, 2009). ESR1 is reported to be a promising candidate gene for boar sperm quality and fertility (Gunawan et al, 2011) and is genetically related to androstenone (Grindflek et al, 2010). To our knowledge, this is the first association study of ESR1 polymorphism with boar taint compounds.…”

“…3) seemed to be consistent with the results of mRNA expression. The CYP21 mRNA is reported to be down regulated in Norwegian Landrace boars with a high androstenone level (Grindflek, Berget, Moe, Oeth, & Lien, 2010). CYP21 is a member of the cytochrome P450 superfamily enzyme, a key enzyme for corticosteroid-ogenesis (Deslandes et al, 2001;Payne & Youngblood, 1995).…”

Skatole metabolites in urine as a biological marker of pigs with enhanced hepatic metabolism

“…There were numerous attempts to identify genetic markers which would allow the selection of free of taint pigs (Duijvesteijn et al, 2010;Gregersen et al, 2012;Gunawan et al, 2013a and2013b). Recently, it was shown that 12 candidate genes in testes of boars with high and low androstenone levels were differentially expressed (Grindflek et al, 2010).…”