Project description:Background: Plasma microRNAs (miRNAs), which exist in exosomal (EX) and non-exosomal free circulating (FC) fractions, can be utilized as blood biomarkers. To identify early indicators of carcass traits, we performed comprehensive analysis of plasma miRNAs separately on EX and FC fractions in Japanese Black cattle at 20, 25, and 30 months of age. Results: We found a total of 1,071 miRNAs including 39 novel miRNA candidates, in which 345 and 358 miRNAs exhibited in measurable amounts in EX and FC fractions, respectively. Profiles of these miRNAs were similar at 20 and 25 months, but collectively different from those at 30 months. We identified 86 and 80 differentially existed miRNAs (DE-miRNAs) between 25 and 30 months in EX and FC fractions, respectively. Among the DE-miRNAs, we revealed significant correlations of bta-miR-150 (EX and FC), -30b-5p (EX), -423-3p (EX), and -222 (FC) with several carcass traits including marbling score. Interestingly, target genes of these DE-miRNAs were functionally enriched in KEGG pathways such as PI3-Akt and MAPK signaling pathways, suggesting their functional relevance to carcass quality and quantity traits. Conclusions: We clarified changes in plasma EX and FC miRNA profiles during the fattening period and identified several miRNAs having correlations with carcass traits. These results could support the utility of plasma miRNAs as potential early indicators of carcass traits in Japanese Black cattle.
Project description:Sex condition has been demonstrated to alter meat quality and sex is a major factor that affects the fatty acid composition of lipids of carcass dissectible or intramuscular depot fats. But the possible genetic molecular mechanism of gender causing meat quality differences is not well defined. Qinchuan cattle, Qinghai yak and Guangxi buffalo are three typical indigenous species of cattle in China. Obivious differences of meat quality exist among the three species of cattle. Few studies have been conducted to elucidate the muscle tissue expression of genes involved in pathways and mechanisms leading to meat quality differences beyond the phenotype properties of beef. Bovine Genome Arrays were used to construct muscle expression profiles of the longuissimus dorsi from Qinchuan cattle at 36 months and screen differentially expressed genes in the longuissimus dorsi muscle tissues among different genders of Qinchuan cattle, between Qinchuan cattle and Qinghai yak, and between Qinchuan cattle and Guangxi buffalo.
Project description:MicroRNAs (miRNAs) regulate gene expression. The aim of this study was to identify circulating miRNAs that are involved with meat yield and connect exosomes and longissimus dorsi (LD) muscle in Korean cattle steer. Thus, we performed analyses of the carcass characteristics, exosome extraction, bovine miRNA array, mature miRNA qPCR, bioinformatics, and qPCR. Our analysis of the carcass characteristics relative to the yield grade (YG) showed that the yield index (YI) and rib eye area were the highest, whereas the backfat thickness was the lowest for YG A cattle among the three YGs. We performed a miRNA microarray and a Venn diagram analysis to sort the circulating miRNAs that connect exosomes and LD muscle. Mature miRNA qPCR showed that miR-15a (r = 0.84), miR-26b (r = 0.91), and miR-29c (r = 0.92) had positive relationships with exosomes and LD muscle. In YG A cattle, miR-26b was considered to be a circulating miRNA connecting exosomes and LD muscle because the expression pattern of miR-26b was similar in the microarray and miRNA qPCR for miR-26b-targeted genes, where the expression levels of DIAPH3 and YOD1 were lower than those in YG C cattle. Our results suggest that circulating miR-26b may participate in cell maintenance by regulating DIAPH3 and YOD1 in the LD muscle of Korean cattle. 29 or 30 month Korean cattle steers were classified by yield grade(YG) A, B, and C. miRNA expression patterns for exosome and LD muscle were compared among YGs.
Project description:Cattle plays an important role in providing essential nutrients through meat production. Thus, we focused on epigenetic factors associated with meat yield. To investigating circulating miRNAs that are involved with meat yield and connect biofluids and longissimus dorsi (LD) muscle in Korean cattle, we performed analyses of the carcass characteristics, miRNA array, qPCR, and bioinformatics. Carcass characteristics relative to the yield grade (YG) showed that the yield index and rib eye area were the highest, whereas the backfat thickness was the lowest for YG A (equal to high yield grade) cattle among the three YGs. miRNA array sorted the circulating miRNAs that connect biofluids and LD muscle. miRNA qPCR showed that miR-15a (r = 0.84), miR-26b (r = 0.91), and miR-29c (r = 0.92) had positive relationships with biofluids and LD muscle. In YG A cattle, miR-26b was considered to be a circulating miRNA connecting biofluids and LD muscle because the target genes of miR-26b was more involved with myogenesis. Then, miR-26b targeted genes, DIAPH3 and YOD1 were downregulated in YG A cattle. Our results suggest that miR-15a, miR-26b, and miR-29c are upregulated in biofluids and LD muscle whereas, downregulation of DIAPH3 and YOD1 in the LD muscle of finishing cattle steers.