SNPs in microRNA seed region and impact of miR-375 in concurrent regulation of multiple lipid accumulation-related genes.

Bovine intramuscular fat (IMF), commonly referred to as marbling, is regulated by lipid metabolism, which includes adipogenesis, lipogenesis, glycerolipid synthesis, and lipolysis. In recent years, breeding researchers have identified single nucleotide polymorphisms (SNPs) as useful marker-assisted selection tools for improving marbling scores in national breeding programs. These included causal SNPs that induce phenotypic variation. MicroRNAs (miRNAs) are small highly conserved non-coding RNA molecules that bind to multiple non-coding regions. They are involved in post-transcriptional regulation. Multiple miRNAs may regulate a given target. Previously, three SNPs in the GPAM 3' UTR and four miRNAs were identified through in silico assays. The aim of this study is to verify the binding ability of the four miRNAs to the SNPs within the 3'UTR of GPAM, and to identify the regulatory function of miR-375 in the expression of genes related to lipid metabolism in mammalian adipocytes. It was verified that the four miRNAs bind to the GPAM 3'UTR, and identified that the miR-375 sequence is highly conserved. Furthermore, it was founded that miR-375 upregulated the GPAM gene, C/EBPα, PPARγ and lipid metabolism-related genes and promoted lipid droplet accumulation in 3T3-L1 cells. In conclusion, these results suggest that miR-375 is a multifunctional regulator of multiple lipid metabolism-related genes and may aid in obesity research as a biomarker.

Programmable Retention Characteristics in MoS2-Based Atomristors for Neuromorphic and Reservoir Computing Systems.

In this study, we investigate the coexistence of short- and long-term memory effects owing to the programmable retention characteristics of a two-dimensional Au/MoS2/Au atomristor device and determine the impact of these effects on synaptic properties. This device is constructed using bilayer MoS2 in a crossbar structure. The presence of both short- and long-term memory characteristics is proposed by using a filament model within the bilayer transition-metal dichalcogenide. Short- and long-term properties are validated based on programmable multilevel retention tests. Moreover, we confirm various synaptic characteristics of the device, demonstrating its potential use as a synaptic device in a neuromorphic system. Excitatory postsynaptic current, paired-pulse facilitation, spike-rate-dependent plasticity, and spike-number-dependent plasticity synaptic applications are implemented by operating the device at a low-conductance level. Furthermore, long-term potentiation and depression exhibit symmetrical properties at high-conductance levels. Synaptic learning and forgetting characteristics are emulated using programmable retention properties and composite synaptic plasticity. The learning process of artificial neural networks is used to achieve high pattern recognition accuracy, thereby demonstrating the suitability of the use of the device in a neuromorphic system. Finally, the device is used as a physical reservoir with time-dependent inputs to realize reservoir computing by using short-term memory properties. Our study reveals that the proposed device can be applied in artificial intelligence-based computing applications by utilizing its programmable retention properties.

Advances in Methane Emission Estimation in Livestock: A Review of Data Collection Methods, Model Development and the Role of AI Technologies.

This review examines the significant role of methane emissions in the livestock industry, with a focus on cattle and their substantial impact on climate change. It highlights the importance of accurate measurement and management techniques for methane, a potent greenhouse gas accounting for 14-16% of global emissions. The study evaluates both conventional and AI-driven methods for detecting methane emissions from livestock, particularly emphasizing cattle contributions, and the need for region-specific formulas. Sections cover livestock methane emissions, the potential of AI technology, data collection issues, methane's significance in carbon credit schemes, and current research and innovation. The review emphasizes the critical role of accurate measurement and estimation methods for effective climate change mitigation and reducing methane emissions from livestock operations. Overall, it provides a comprehensive overview of methane emissions in the livestock industry by synthesizing existing research and literature, aiming to improve knowledge and methods for mitigating climate change. Livestock-generated methane, especially from cattle, is highlighted as a crucial factor in climate change, and the review underscores the importance of integrating precise measurement and estimation techniques for effective mitigation.

Volatile and Nonvolatile Resistive Switching Coexistence in Conductive Point Hexagonal Boron Nitride Monolayer.

Recently, we demonstrated the nonvolatile resistive switching effects of metal-insulator-metal (MIM) atomristor structures based on two-dimensional (2D) monolayers. However, there are many remaining combinations between 2D monolayers and metal electrodes; hence, there is a need to further explore 2D resistance switching devices from material selections to future perspectives. This study investigated the volatile and nonvolatile switching coexistence of monolayer hexagonal boron nitride (h-BN) atomristors using top and bottom silver (Ag) metal electrodes. Utilizing an h-BN monolayer and Ag electrodes, we found that the transition between volatile and nonvolatile switching is attributed to the thickness/stiffness of chain-like conductive bridges between h-BN and Ag surfaces based on the current compliance and atomristor area. Computations indicate a "weak" bridge is responsible for volatile switching, while a "strong" bridge is formed for nonvolatile switching. The current compliance determines the number of Ag atoms that undergo dissociation at the electrode, while the atomristor area determines the degree of electric field localization that forms more stable conductive bridges. The findings of this study suggest that the h-BN atomristor using Ag electrodes shows promise as a potential solution to integrate both volatile neurons and nonvolatile synapses in a single neuromorphic crossbar array structure through electrical and dimensional designs.

Diagnostic Efficacy of Serum Asialo α1-Acid Glycoprotein Levels for Advanced Liver Fibrosis and Cirrhosis in Patients with Chronic Hepatitis B Compared to That in Healthy Subjects: A Prospective Study.

Background: Serum asialo α1-acid gycoprotein (AsAGP) is a novel biomarker specific to liver fibrosis. Aim: To evaluate the diagnostic efficacy of serum AsAGP levels in classifying the severity of liver fibrosis and differentiating liver cirrhosis (LC) in patients with chronic hepatitis B (CHB) from healthy controls. Methods: Overall, 206 subjects were prospectively enrolled. LC was diagnosed based on liver stiffness levels (>11 kPa) measured using transient elastography. Serum AsAGP levels were measured using an antibody-lectin sandwich immunoassay. We investigated the diagnostic performance by comparing serum AsAGP levels among healthy control, CHB, and CHB with LC groups. Sensitivity, specificity, and optimal AsAGP cut-off values were also calculated. Results: Serum AsAGP levels were significantly different between healthy controls, CHB patients, and CHB patients with LC (1.04 ± 0.31 µg/mL, 1.12 ± 0.34 µg/mL, 1.51 ± 0.43 µg/mL respectively; p < 0.001). Serum AsAGP levels positively correlated with liver stiffness (r = 0.46, p < 0.001). AUROC of healthy control versus CHB with LC was 0.821 (p < 0.001, optimal cut-off 1.036 µg/mL). AUROC of healthy control versus CHB was 0.624 (p = 0.049, optimal cut-off level 0.934 µg/mL). AUROC of CHB versus CHB with LC was 0.765, (p < 0.001, optimal cut-off 1.260 µg/mL). Conclusions: Serum AsAGP levels in CHB patients with LC were significantly higher than those in healthy controls and CHB patients. AsAGP levels showed good diagnostic performance in predicting advanced fibrosis and cirrhosis, which suggests a potential role as a biomarker for predicting the progression of liver disease in CHB.

DNA Methylation Patterns According to Fatty Liver Index and Longitudinal Changes from the Korean Genome and Epidemiology Study (KoGES).

The role of differentially methylated regions (DMRs) in nonalcoholic fatty liver disease (NAFLD) is unclear. This study aimed to identify the role of DMR in NAFLD development and progression using the Korean Genome and Epidemiology Study (KoGES) cohort. We used laboratory evaluations and Illumina Methylation 450 k DNA methylation microarray data from KoGES. The correlation between fatty liver index (FLI) and genomic CpG sites was analyzed in 322 subjects. Longitudinal changes over 8 years were confirmed in 33 subjects. To identify CpG sites and genes related to FLI, we obtained enrichment terms for 6765 genes. DMRs were identified for both high (n = 128) and low (n = 194) groups on the basis of FLI 30 in 142 men and 180 women. To confirm longitudinal changes in 33 subjects, the ratio of follow-up and baseline investigation values was obtained. Correlations and group comparisons were performed for the 8 year change values. PITPNM3, RXFP3, and THRB were hypermethylated in the increased FLI groups, whereas SLC9A2 and FOXI3 were hypermethylated in the decreased FLI groups. DMRs describing NAFLD were determined, and functions related to inflammation were identified. Factors related to longitudinal changes are suggested, and blood circulation-related functions appear to be important in the management of NAFLD.

Allele-specific polymerase chain reaction for the discrimination of elite Korean cattle associated with high beef quality and quantity.

Techniques such as direct sequencing and PCR-RFLP (restriction fragment length polymorphism) are widely used to analyze the genotypes of livestock. However, these conventional methods have the disadvantage of taking a lot of time and incurring considerable cost. The allele-specific PCR method performs PCR using two primers, and a single nucleotide polymorphism (SNP) genotype can be identified through electrophoresis, saving time and cost. Highly accurate results can be obtained by designing specific primers according to the allele of the SNP under study, utilizing primer binding to a complementary matching sequence. In this study, we established a genotyping system with the AS-PCR technique, using SNPs related to the improvement of the meat quality and meat mass of Korean cattle. Using the PRIMER1 program, we designed specific primers for SNPs located at the 3 ' end, with one SNP marker in the HSPB1 gene related to meat quantity and two SNP markers in the ADH1C and FASN genes related to meat quality in cattle. AS-PCR was performed on 10 Korean cattle using the primers designed with this system, and the genotypes could be identified by the size of the PCR product amplified as a result of electrophoresis. In the case of the HSPB1 g.2352T  >  C SNP, the T allele was amplified to 148 bp, and the C allele was amplified to 222 bp. The ADH1C c.-64T  >  C SNP was amplified to 492 bp at the T allele and 330 bp at the C allele. The FASN g.17924G  >  A SNP A allele was amplified to 377 bp and the G allele to 507 bp. The results for each SNP genotype were verified using direct sequencing, which showed that the genotypes identified by direct sequencing and the genotypes identified by the AS-PCR method matched exactly. The AS-PCR method therefore appears to be valuable for use in a genotyping system.

Effects of L-glutamine supplementation on degradation rate and rumen fermentation characteristics in vitro.

OBJECTIVE: Two follow-up studies (exp. 1 and 2) were conducted to determine the effects of L-glutamine (L-Gln) supplementation on degradation and rumen fermentation characteristics in vitro. METHODS: First, rumen liquor from three cannulated cows was used to test L-Gln (50 mM) degradation rate and ammonia-N production at 6, 12, 24, 36, and 48 h after incubation (exp. 1). Second, rumen liquor from two cannulated steers was used to assess the effects of five levels of L-Gln including 0% (control), 0.5%, 1%, 2%, and 3% at 0, 3, 6, 12, 24, 36, and 48 h after incubation on fermentation characteristics, gas production, and degradability of nutrients (exp. 2). RESULTS: In exp. 1, L-Gln degradation rate and ammonia-N concentrations increased over time (p<0.001). In exp. 2, pH was reduced significantly as incubation time elapsed (p<0.001). Total gas production tended to increase in all groups as incubation time increased. Acetate and propionate tended to increase by increasing glutamine (Gln) levels, whereas levels of total volatile fatty acids (VFAs) were the highest in 0.5% and 3% Gln groups (p<0.001). The branched-chain VFA showed both linear and quadratic effects showing the lowest values in the 1% Gln group particularly after 6 h incubation (p<0.001). L-Gln increased crude protein degradability (p<0.001), showing the highest degradability in the 0.5% Gln group regardless of incubation time (p<0.05). Degradability of acid detergent fiber and neutral detergent fiber showed a similar pattern showing the highest values in 0.5% Gln group (p<0.10). CONCLUSION: Although L-Gln showed no toxicity when it was supplemented at high dosages (2% to 3% of DM), 0.5% L-Gln demonstrated the positive effects on main factors including VFAs production in-vitro. The results of this study need to be verified in further in-vivo study.

Evaluation of the severity of nonalcoholic fatty liver disease through analysis of serum exosomal miRNA expression.

Noninvasive techniques for evaluating the severity of nonalcoholic fatty liver disease (NAFLD) have shown limited diagnostic performance. MicroRNAs (miRNAs) are useful biomarkers for diagnosing and monitoring the progression and treatment response to several diseases. Here, we evaluated whether serum exosomal miRNAs could be used for the diagnosis and prognosis of NAFLD severity. Exosomal miRNAs were isolated from the sera of 41 patients with NAFLD (diagnosed using liver biopsy) for microarray profiling. The degree of NAFLD severity was determined using inflammation, steatosis, and ballooning scores and the NAFLD activity score (NAS). Correlations between miRNA expression, clinical and biochemical parameters, and mRNA expression were analyzed. Overall, 25, 11, 13, and 14 miRNAs correlated with the inflammation score, steatosis score, ballooning score, and NAS, respectively, with 33 significant correlations observed between 27 miRNAs and six clinical variables. Eight miRNAs (let-7b-5p, miR-378h, -1184, -3613-3p, -877-5p, -602, -133b, and 509-3p) showed anticorrelated patterns with the corresponding mRNA expression. In fibrosis, 52 and 30 interactions corresponding to high miRNA-low mRNA and low miRNA-high mRNA expression, respectively, were observed. The present results therefore suggest that serum exosomal miRNAs can be used to evaluate NAFLD severity and identify potential targets for NAFLD treatment.

Circulating miRNA is a useful diagnostic biomarker for nonalcoholic steatohepatitis in nonalcoholic fatty liver disease.

Nonalcoholic steatohepatitis (NASH) is considered as a progressive form of nonalcoholic fatty liver disease (NAFLD). To distinguish NASH from nonalcoholic fatty liver (NAFL), we evaluated the diagnostic value of circulating miRNAs. Small RNA sequencing was performed on 12 NAFL patients and 12 NASH patients, and the miRNA expression was compared. After selecting miRNAs for the diagnosis of NASH, we analyzed the diagnostic accuracy of each miRNA and the combination of miRNAs. External validation was performed using quantitative reverse transcription PCR. Among the 2,588 miRNAs, 26 miRNAs significantly increased in the NASH group than in the NAFL group. Among the 26 elevated miRNAs in the NASH group, 8 miRNAs were selected, and in silico analysis was performed. Only four miRNAs (miR-21-5p, miR-151a-3p, miR-192-5p, and miR-4449) showed significant area under the receiver operating characteristic curve (AUC) values for NASH diagnosis. The combination of the four miRNAs showed satisfactory diagnostic accuracy for NASH (AUC 0.875; 95% CI 0.676-0.973). External validation revealed similar diagnostic accuracy for NASH (AUC 0.874; 95% CI 0.724-0.960). NASH represents significantly distinct miRNA expression profile compared with NAFL. The combination of serum circulating miRNAs can be used as a novel biomarker for the NASH diagnosis in NAFLD.

Determination of the effect of functional single-nucleotide polymorphisms associated with glycerolipid synthesis on intramuscular fat deposition in Korean cattle steer.

Intramuscular fat deposition in the longissimus dorsi muscle (LM) of Korean cattle steer is regulated by several genes related to lipid metabolism. One of these genes encodes the enzyme bovine glycerol-3-phosphate acyltransferase, mitochondrial (GPAM), which is located on the mitochondrial outer membrane and catalyzes the initial and committed step of glycerolipid synthesis in lipid metabolism of cattle. Previous studies have shown that the 3 ' -untranslated region (UTR) of the GPAM is quite extended and contains a polyadenylation signal site, erythroid 15-lipoxygenase differentiation control elements (15-LOX-DICEs), and cytoplasmic polyadenylation elements (CPEs) that affect the regulation of triacylglycerol synthesis. Therefore, the aim of this study was to identify single-nucleotide polymorphisms (SNPs) related to the regulation of glycerolipid synthesis in the 3 ' -UTR of GPAM and to verify the function of SNPs affecting the deposition of intramuscular fat in Korean cattle steer. In the present study, 11 SNPs were discovered in the 3 ' -UTR of GPAM. Among these SNPs, g.54853A > G, g.55441A > G, and g.55930C > T were significantly associated with marbling score in a Korean cattle steer population and were strongly correlated with each other within the GPAM gene. Furthermore, based on the results predicted by the RNAhybrid program, four putative microRNAs (miRNAs) were identified, and the above SNPs were found to present in the seed region of these miRNAs. These miRNAs have a differential binding affinity for each allele of SNPs g.54853A > G, g.55441A > G, and g.55930C > T. The in vivo evidence of intramuscular fat deposition in the LM tissue showed that these SNPs affected the regulation of intramuscular fat deposition in Korean cattle steer. Thus, the g.54853A > G, g.55441A > G, and g.55930C > T could be considered as causal mutations regulating intramuscular fat deposition in Korean cattle steer.

Early Normalization of Alanine Aminotransferase during Antiviral Therapy Reduces Risk of Hepatocellular Carcinoma in HBV Patients.

Potent antiviral agents effectively reduce liver-related events in patients with chronic hepatitis B. This study aimed to determine whether alanine aminotransferase normalization using potent antiviral agents was related to hepatocellular carcinoma development. From 2007 to 2017, we included 610 patients with chronic hepatitis B who received entecavir or tenofovir disoproxil fumarate. The patients were divided into the alanine aminotransferase normalization group (Gr.1) and non-normalization group (Gr.2) within a year of potent antiviral treatment. Liver-related events included hepatic encephalopathy, variceal bleeding, and ascites. The mortality rate and hepatocellular carcinoma incidence were investigated for each group. The patients who showed ALT normalization at 1 year of treatment were 397 (65.1%) of 610. During a median follow-up period of 86 months, 65 (10.7%) patients developed hepatocellular carcinoma. The cumulative incidence of hepatocellular carcinoma was significantly lower in Gr.1 than in Gr.2 (p < 0.001). Risk factors for alanine aminotransferase non-normalization were body mass index, cholesterol, and liver cirrhosis at baseline. Male sex, age, platelet level, alcohol use, presence of cirrhosis at baseline, and non-normalization after 1 year of treatment were independent risk factors for hepatocellular carcinoma. Alanine aminotransferase normalization within 1 year of initiating antiviral agents reduces the risk of hepatocellular carcinoma development.

A Case of Vanishing Bile Duct Syndrome after Drug-Induced Liver Injury Caused by Pelubiprofen.

Vanishing bile duct syndrome (VBDS) is a rare disease characterized by ductopenia and cholestasis, and is linked to immunological damage to the bile duct system. VBDS can be triggered by infection, ischemia, autoimmune diseases, adverse drug reactions, and humoral factors associated with malignancy. A few cases of VBDS associated with nonsteroidal anti-inflammatory drug-related drug-induced liver injury (DILI) have been reported. Here, we report a case of a 29-year-old patient who developed DILI that progressed to VBDS after the administration of pelubiprofen.

The effect of single-nucleotide polymorphisms within heat shock protein beta 1 on beef quantity in Korean native steers.

Heat shock protein beta 1 (HSPB1), a member of the heat-shock family of protein, is a relatively small (27 kDa) molecular chaperone protein associated with cellular development. The relationship between HSPB1 expression and muscle growth in beef cattle has previously been reported, but there have been no reports of DNA markers related to meat quantity in Korean native steers. Therefore, the aim of this study was to evaluate the relationship of single-nucleotide polymorphisms (SNPs) within HSPB1 in terms of the carcass traits related to muscle growth in Korean native steers. Through direct sequencing, we discovered three SNPs: g.111 T > C SNP (rs208395876) and g.2548 C > G SNP (rs483014585) were respectively located in 5 '  UTR (untranslated region) and 3 '  UTR. Further, g.2352 T > C SNP (rs110832311) was located in the adjacent region of the RNA splicing site. The least square means of steers with a CC genotype of g.111 T > C SNP had a significantly higher meat ratio ( P   =  0.04), while the least square means of steers with a CC genotype of g.2352 T > C SNP had a significantly higher meat ratio ( P   =  0.002) and lower back-fat thickness ( P   =  0.004) than those of the other genotype. Moreover, although the least square means of steers with CC-CC, CT-CC, and TT-CC genotypes were significantly decreased for back-fat thickness, they were significantly increased for the meat ratio. Therefore, our results suggested that g.111 T > C SNP and g.2352 T > C SNP could be a causal mutation related to an adipose metabolism in Korean cattle steer.

The impact of unmeasured within- and between-cluster confounding on the bias of effect estimatorsof a continuous exposure.

Unmeasured confounding almost always exists in observational studies and can bias estimates of exposure effects. Instrumental variable methods are popular choices in combating unmeasured confounding to obtain less biased effect estimates. However, we demonstrate that alternative methods may give less biased estimates depending on the nature of unmeasured confounding. Treatment preferences of clusters (e.g. physician practices) are the most frequently used instruments in instrumental variable analyses. These preference-based instrumental variable analyses are usually conducted on data clustered by region, hospital/facility, or physician, where unmeasured confounding often occurs within or between clusters. We aim to quantify the impact of unmeasured confounding on the bias of effect estimators in instrumental variable analysis, as well as several common alternative methods including ordinary least squares regression, linear mixed models, and fixed-effect models to study the effect of a continuous exposure (e.g. treatment dose) on a continuous outcome. We derive closed-form expressions of asymptotic bias of estimators from these four methods in the presence of unmeasured within- and/or between-cluster confounders. Simulations demonstrate that the asymptotic bias formulae well approximate bias in finite samples for all methods. The bias formulae show that instrumental variable analyses can provide consistent estimates when unmeasured within-cluster confounding exists, but not when between-cluster confounding exists. On the other hand, fixed-effect models and linear mixed models can provide consistent estimates when unmeasured between-cluster confounding exits, but not for within-cluster confounding. Whether instrumental variable analyses are advantageous in reducing bias over fixed-effect models and linear mixed models depends on the extent of unmeasured within-cluster confounding relative to between-cluster confounding. Furthermore, the impact of unmeasured between-cluster confounding on instrumental variable analysis estimates is larger than the impact of unmeasured within-cluster confounding on fixed-effect model and linear mixed model estimates. We illustrate the use of these methods in estimating the effect of erythropoiesis stimulating agents on hemoglobin levels. Our findings provide guidance for choosing appropriate methods to combat the dominant types of unmeasured confounders and help interpret statistical results in the context of unmeasured confounding.

Erratum to: Study on the fatty acid profile of phospholipid and neutral lipid in Hanwoo beef and their relationship to genetic variation.

[This corrects the article DOI: 10.5187/jast.2019.61.2.69.].

Study on the fatty acid profile of phospholipid and neutral lipid in Hanwoo beef and their relationship to genetic variation.

Maize which has very high omega-6 fatty acid content has been used as a main feed grain for Hanwoo beef production to increase marbling, and thus omega-6 to omega-3 fatty acids ratio in Hanwoo beef is expected to be biased. To elucidate the current status of omega fatty acids ratio in Hanwoo beef, fatty acid profiles of neutral lipid and phospholipid fraction were analyzed separately using 55 Hanwoo steers' longissimus dorsi muscle slaughtered at Pyeongchang, Korea from Oct. to Nov. 2015. In addition, an association study was conducted to evaluate associations between single nucleotide polymorphism (SNP) markers from references and omega fatty acid profiles in phospholipid of Hanwoo beef samples using analysis of variance (ANOVA). In neutral lipid fraction, composition of saturated and monounsaturated fatty acids was higher and polyunsaturated fatty acids was lower compared to those in phospholipid fraction. The mean n-6/n-3 ratios of Hanwoo were 56.059 ± 16.180 and 26.811 ± 6.668 in phospholipid and neutral lipid, respectively. There were three SNPs showing statistically significant associations with omega fatty acid content. GA type of rs41919985 in fatty acid synthase (FASN) was significantly associated with the highest amount of C20:5 n-3 (p = 0.031). CC type of rs41729173 in fatty acid-binding protein 4 (FABP4) was significantly associated with the lowest amount of C22:2n-6 (p = 0.047). AG type of rs42187261 in FADS1 was significantly linked to the lowest concentration of C20:4 n-6 (p = 0.044). The total n-6/n-3 ratio of the steer which has all four SNP types in above loci (27.905) was much lower than the mean value of the total n-6/n-3 ratio in phospholipid of the 55 Hanwoo steers (56.059 ± 16.180). It was found that phospholipid and neutral lipid of Hanwoo have very high n-6/n-3 ratios compared to the reported data from different cow breeds. Four SNPs in genes related with fatty acid metabolism showed significant associations with the fatty acid profile of phospholipid and may have potential as SNP markers to select Hanwoo steers in terms of n-6/n-3 balance in the future.

Effect of glutamine on heat-shock protein beta 1 (HSPB1) expression during myogenic differentiation in bovine embryonic fibroblast cells.

The objective of this study was to examine the effects of glutamine on heat-shock protein beta 1 (HSPB1) expression in bovine embryonic fibroblast cells during myogenesis. First, to elucidate the role of glutamine on HSPB1 expression during myogenesis, we treated with glutamine in myogenic lineage determinant (MyoD) over-expressed bovine embryonic fibroblast cells (BEFS-MyoD cells). Second, knockdown of HSPB1 using small interference RNA was performed to evaluate whether muscle development by glutamine is dependent on HSPB1 in BEFS-MyoD cells. As a result, glutamine promoted the mRNA level of HSPB1, Myogenin, Desmin, and mTOR as well as myotube formation, and protein synthesis (p < 0.05). The inhibition of HSPB1 expression during myogenesis has shown to repress the expression of myogenic marker genes (MyoD, Myogenin, Desmin) (p < 0.01), formation of myotubes and protein synthesis (p < 0.05). According to the results, it is concluded that glutamine regulates HSPB1 expression during myogenesis.

Superior single nucleotide polymorphisms that contribute to two main routes of the fatty acid synthesis pathway in Korean cattle.

The fatty acid composition of adipose tissue in livestock has been recognized as an important carcass trait that affects meat quality. To determine the overall positive effect on fatty acid synthesis, we investigated PPARγ, SREBPs, FABP4, SCD, and FASN genes because SNP and/or SNP combinations were strongly affecting each fatty acid synthesis pathway. We screened their SNPs, SNP combinations, and genotype. Furthermore, we studied the economic traits C18:1, monounsaturated fatty acid (MUFA), and marbling score (MS). To enhance the accuracy of the predictive genetic effect, we applied a statistical adjustment model excluding environmental factors. We also selected superior genes, gene combinations, and genotypes for each economic trait by using multifactor dimensionality reduction. Based on the results, g.3977-325 T>C (CC) was selected as the best genotype of the SNP and the combination (g.10153 A>G, g.3977-325 T>C) (AACC, AGCC, GGCC), (g.3690 G>A, g.3977-325 T>C) (GGCC, GACC), (g.3977-325 T>C, g.25670 C>T) (CCCC, CCCT, CCTT) (genotypes of the best SNP combination) was selected as the best gene combination for C18:1 and MUFA. In addition, g.3977-325 T>C (CC) was selected as the best genotype of the SNP and the combination (g.3977-325 T>C, g.6974 G>A) (TTAA, CTAA, CCAA, CCGA, CCGG) as the best SNP combination for MS. We integrated genes that were selected as excellent SNP and SNP combinations affecting two main routes of the fatty acid synthesis pathway and identified the best and final SNP, SNP combination, and superior genotype.

In vivo evidence on the functional variation within fatty acid synthase gene associated with lipid metabolism in bovine longissimus dorsi muscle tissue.

In Korean cattle, intramuscular fat (IMF), or marbling, of the longissimus dorsi muscle (LM) cross section is one of the most important indicators of beef quality and are influenced by environmental and genetic factors. This study was to evaluate the effect of SNPs on the beef quality in Korean cattle for functional studies, such as site-directed mutagenesis based on bovine adipocytes. The fatty acid synthase (FASN) gene plays an important role in lipogenesis. FASN is an essential metabolic and multifunctional enzyme in fatty acid synthesis. Several studies have reported that SNPs g.841G, g.16024A, g.16039T, and g.17924G have a significant impact on marbling scores in Korean cattle and Japanese Black cattle population. These SNPs are located in transcription factor binding sites, the beta-ketoacyl reductase, and thioesterase domains. Our results revealed that the g.17924 A>G SNP is located in the thioesterase domain of the FASN protein, and changes from polar, neutral, and hydrophilic to nonpolar, aliphatic, and hydrophobic, respectively. In in vivo LM tissue of Korean cattle, the g.17924A>G SNP has an effect on increasing fat deposition. Therefore, g.17924A>G SNP could be a causal mutation for increasing fat deposition in Korean cattle LM tissue.