• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.953-957
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• 2006

The eukaryotic elongation factor 1 A (EEF1A) participates in protein synthesis by forming the eEF1A GTP tRNA complex to deliver aminoacyl-tRNA to the A site of ribosomes. This study described cDNA sequences and partial genomic structure of porcine EEF1A1. The porcine EEF1A1 gene encoded a protein with 462 amino acids, which shared complete homology with human, chimpanzee and dog. The temporal expression pattern showed the diversity of EEF1A1 level in mRNA was relatively minor in prenatal embryo skeletal muscle, however, the expression decreased during aging after birth in skeletal muscle of the Chinese Tongcheng pig. The spatial expression patterns indicated that the gene expressed in skeletal muscle, heart, lung, liver, kidney, fat and spleen. In addition, we assigned the gene to porcine chromosome 1 using a radiation hybrid panel.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.2
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• pp.170-175
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• 2019

Objective: Uncoupling protein 3 gene (UCP3) is a candidate gene associated with the meat quality of pigs. The aim of this study was to explore the regulation mechanism of UCP3 expression and provide a theoretical basis for the research of the function of porcine UCP3 gene in meat quality. Methods: Bisulfite sequencing polymerase chain reaction (PCR) and quantitative real-time PCR (Q-PCR) were used to analyze the methylation of UCP3 5′-flanking region and UCP3 mRNA expression in the adipose tissue or skeletal muscle of three pig breeds at different ages (1, 90, 210-day-old Putian Black pig; 90-day-old Duroc; and 90-day-old Dupu). Results: Results showed that two cytosine-guanine dinucleotide (CpG) islands are present in the promoter region of porcine UCP3 gene. The second CpG island located in the core promoter region contained 9 CpG sites. The methylation level of CpG island 2 was lower in the adipose tissue and skeletal muscle of 90-day-old Putian Black pigs compared with 1-day-old and 210-day-old Putian Black pigs, and the difference also existed in the skeletal muscle among the three 90-day-old pig breeds. Furthermore, the obvious changing difference of UCP3 mRNA expression was observed in the skeletal muscle of different groups. However, the difference of methylation status and expression level of UCP3 gene was not significant in the adipose tissue. Conclusion: Our data indicate that UCP3 mRNA expression level was associated with the methylation status of UCP3 promoter in the skeletal muscle of pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.417-424
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• 2003

Inhibitory activities against angiotensin I-converting enzyme (ACE) of enzymatic hydrolysates of porcine skeletal muscle proteins were investigated. Myosin B, myosin, actin, tropomyosin, troponin and water-soluble proteins extracted from pork loin were digested by eight kinds of proteases, including pepsin, $\alpha$-chymotrypsin, and trypsin. After digestion, hydrolysates produced from all proteins showed ACE inhibitory activities, and the peptic hydrolysate showed the strongest activity. In the case of myosin B, the molar concentration of peptic hydrolysate required to inhibit 50% of the activity increased gradually as digestion proceeded. The hydrolysates produced by sequential digestion with pepsin and $\alpha$-chymotrypsin, pepsin and trypsin or pepsin and pancreatin showed weaker activities than those by pepsin alone, suggesting that ACE inhibitory peptides from peptic digestion might lose their active sequences after digestion by the second protease. However, the hydrolysates produced by sequential digestion showed stronger activities than those by $\alpha$-chymotrypsin, trypsin or pancreatin alone. These results suggested that the hydrolysates of porcine meat were able to show ACE inhibitory activity, even if they were digested in vivo, and that pork might be a useful source of physiologically functional factors.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1612-1617
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• 2007

In this study, we have compared the skeletal muscle proteome at various stages of porcine postnatal development. Korean native pigs were divided into five postnatal stages of 30, 70, 130, 170 and 300 d and their loin muscles were analyzed for muscle proteome by using two-dimensional electrophoresis and mass spectrometry. We found 5 proteins showing a consistent pattern during skeletal muscle growth. Four proteins were identified as myosin light chain 1 slow-twitch (MLC1sa) isoform, troponin T, triosephosphate isomerase (TIP) and DJ-1 protein. The remaining protein was not identified. Two muscle fiber proteins of MLC1sa isoform and troponin T showed a high expression level at an early postnatal stage and then their levels were decreased markedly during growth stages. On the other hand, the expression of TIP and DJ-1 protein, which are well known as catalysis enzyme and antioxidant-related protein, respectively, were linearly increased during growth stages. Thus, the stage-related muscle proteins may be useful as parameters for understanding the developmental characteristics of biochemical and physiological properties in Korean native pig skeletal muscle.

• BMB Reports
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• v.43 no.2
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• pp.140-145
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• 2010

The present study investigated whether the mammalian target of rapamycin (mTOR) signal pathway is involved in the regulation of high glucose-induced intramuscular adipogenesis in porcine muscle satellite cells. High glucose (25 mM) dramatically increased intracellular lipid accumulation in cells during the 10-day adipogenic differentiation period. The expressions of CCAAT/enhancer binding protein-$\alpha$ (C/EBP-$\alpha$) and fatty acid synthase (FAS) protein were gradually enhanced during the 10-day duration while mTOR phosphorylation and sterol-regulatory- element-binding protein (SREBP)-1c protein were induced on day 4. Moreover, inhibition of mTOR activity by rapamycin resulted in a reduction of SREBP-1c protein expression and adipogenesis in cells. Collectively, our findings suggest that the adipogenic differentiation of porcine muscle satellite cells and a succeeding extensive adipogenesis, which is triggered by high glucose, is initiated by the mTOR signal pathway through the activation of SREBP-1c protein. This process is previously uncharacterized and suggests a cellular mechanism may be involved in ectopic lipid deposition in skeletal muscle during type 2 diabetes.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.931-937
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• 2006

The full-length cDNA of the porcine SMPX gene was obtained by the rapid amplification of cDNA ends (RACE). The nucleotide sequences and the predicted protein sequences share high sequence identity with both human and mouse. The promoter of SMPX was sequenced and then analyzed to find the promoter binding sites. The reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that SMPX has a high level of expression in heart and skeletal muscle, a very low expression in lung and spleen and no expression in liver, kidney, fat and brain. Moreover, SMPX has a differential expression level in skeletal muscle, the expression in 65-day embryos being higher than other stages. The porcine SMPX was mapped to SSCXp24 by using a somatic cell hybrid panel (SCHP) and was found closely linked to SW1903 using the radiation hybrid panel IMpRH. An A/G single nucleotide polymorphism (PCR-RFLP) in the 3'-untranslated region (3'-UTR) was detected in eight breeds. The analysis of allele frequency distribution showed that introduced pig breeds (Duroc and Large White) have a higher frequency of allele A while in the Chinese indigenous pig breeds (Qingping pig, Lantang pig, YushanBlack pig, Large Black-White pig, Small Meishan) have a higher frequencies of allele G. The association analysis using an experimental population (188 pigs), which included two cross-bred groups and three pure-blood groups, suggested that the SNP genotype was associated with intramuscular fat content.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.4
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• pp.457-463
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• 2016

The goal of this work was to investigate the correlations between MyHC mRNA transcription and their corresponding protein expressions in porcine longissimus muscle (LM) during postnatal growth of pigs. Five DLY ($Duroc{\times}Landrace{\times}Yorkshire$) crossbred pigs were selected, slaughtered and sampled at postnatal 7, 30, 60, 120, and 180 days, respectively. Each muscle was subjected to quantity MyHCs protein contents through an indirect enzyme-linked immunosorbent assay (ELISA), to quantity myosin heavy-chains (MyHCs) mRNA abundances using real-time polymerase chain reaction. We calculated the proportion (%) of each MyHC to total of four MyHC for two levels, respectively. Moreover, the activities of several key energy metabolism enzymes were determined in LM. The result showed that mRNA transcription and protein expression of MyHC I, IIa, IIx and IIb in LM all presented some obvious changes with postnatal aging of pigs, especially at the early stage after birth, and their mRNA transcriptions were easy to be influenced than their protein expressions. The relative proportion of each MyHC mRNA was significantly positively related to that of its corresponding protein (p<0.01), and MyHC I mRNA proportion was positively correlated with creatine kinase (CK), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) activities (p<0.05). These data suggested that MyHC mRNA transcription can be used to reflect MyHC expression, metabolism property and adaptive plasticity of porcine skeletal muscles, and MyHC mRNA composition could be a molecular index reflecting muscle fiber type characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1473-1477
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• 2007

Four-and-a-half LIM-only protein 3 (FHL3) is a member of the LIM protein superfamily and can participate in mediating protein-protein interaction by binding one another through their LIM domains. In this study, the 5'- and 3'- cDNA ends were characterized by RACE (Rapid Amplification of the cDNA Ends) methodology in combination with in silico cloning based on the partial cDNA sequence obtained. Bioinformatics analysis showed FHL3 protein contained four LIM domains and four LIM zinc-binding domains. In silico mapping assigned this gene to the gene cluster MTF1-INPP5B-SF3A3-FHL3-CGI-94 on pig chromosome 6 where several QTL affecting intramuscular fat and eye muscle area had previously been identified. Transcription of the FHL3 gene was detected in spleen, liver, kidney, small intestine, skeletal muscle, fat and stomach, with the greatest expression in skeletal muscle. The A/G polymorphism in exon II was significantly associated with birth weight, average daily gain before weaning, drip loss rate, water holding capacity and intramuscular fat in a Landrace-derived pig population. Together, the present study provided the useful information for further studies to determine the roles of FHL3 gene in the regulation of skeletal muscle cell growth and differentiation in pigs.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.768-774
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• 2007

To study the effect of dietary docosahexaenoic acid (DHA) enrichment on the expression of hepatic genes in pigs, weaned, crossbred pigs (30 d old) were fed diets supplemented with either 2% tallow or DHA oil for 18 d. Hepatic mRNA was extracted. Suppression subtractive hybridization was used to explore the hepatic genes that were specifically regulated by dietary DHA enrichment. After subtraction, we observed 288 cDNA fragments differentially expressed in livers from pigs fed either 2% DHA oil or 2% tallow for 18 d. After differential screening, 7 genes were found to be differentially expressed. Serum amyloid A protein 2 (SAA2) was further investigated because of its role in lipid metabolism. Northern analysis indicated that hepatic SAA2 was upregulated by dietary DHA enrichment (p<0.05). In a second experiment, feeding 10% DHA oil for 2d significantly increased the expression of SAA2 (compared to the 10% tallow group; p<0.05). The porcine SAA2 full length cDNA sequence was cloned and the sequence was compared to the human and mouse sequences. The homology of the SAA2 amino acid sequence between pig and human was 73% and between pig and mouse was 62%. There was a considerable difference in SAA2 sequences among these species. Of particular note was a deletion of 8 amino acids, in the pig compared to the human. This fragment is a specific characteristic for the SAA subtype that involved in acute inflammation reaction. Similar to human and mouse, porcine SAA2 was highly expressed in the liver of pigs. It was not detectable in the skeletal muscle, heart muscle, spleen, kidney, lung, and adipose tissue. These data suggest that SAA2 may be involved in mediation of the function of dietary DHA in the liver of the pig, however, the mechanism is not yet clear.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1349-1353
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• 2007

Calcineurin is a calmodulin dependent protein that functions as a regulator of muscle cell growth and function. Agents capable of interacting with calcineurin could have important applications in muscle disease treatment as well as in the improvement of livestock production. Calsarcins comprise a family of muscle-specific calcineurin binding proteins which play an important role in modulating the function of calcineurin in muscle cells. Recently, we described the first two members of the calsarcin family (calsarcin-1 and calsarcin-2) in the pig. Here, we characterized the third member of the calsarcin family, calsarcin-3, which is also expressed specifically in skeletal muscle. However, unlike calsarcin-1 and calsarcin-2, the calsarcin-3 mRNA expression in skeletal muscle kept rising throughout the prenatal and postnatal development periods. In addition, radiation hybrid mapping indicated that porcine calsarcin-3 mapped to the distal end of the q arm of pig chromosome 2 (SSC2). A C/T single nucleotide polymorphism site in exon 5 was genotyped using the denaturing high performance liquid chromatography (DHPLC) method and the allele frequencies at this locus were significantly different among breeds.