MicroRNAs (miRNAs) play a vital role in improving meat quality by binding to messenger RNAs (mRNAs). We performed an integrated analysis of miRNA and mRNA expression profiling between bulls and steers based on the differences in meat quality traits. Fat and fatty acids are the major phenotypic indices of meat quality traits to estimate between-group variance. In the present study, 90 differentially expressed mRNAs (DEGs) and 18 differentially expressed miRNAs (DEMs) were identified. Eighty-three potential DEG targets and 18 DEMs were used to structure a negative interaction network, and 75 matching target genes were shown in this network. Twenty-six target genes were designated as intersection genes, screened from 18 DEMs, and overlapped with the DEGs. Seventeen of these genes enriched to 19 terms involved in lipid metabolism. Subsequently, 13 DEGs and nine DEMs were validated using quantitative real-time PCR, and seven critical genes were selected to explore the influence of fat and fatty acids through hub genes and predict functional association. A dual-luciferase reporter and Western blot assays confirmed a predicted miRNA target (bta-miR-409a and PLIN5). These findings provide substantial evidence for molecular genetic controls and interaction among genes in cattle.

Producing aflatoxin-detoxifizyme (ADTZ) in pigs to control the AFT contamination of pig feed is a new research strategy by transgenic technology. In this study, transgenic pigs specifically expressing ADTZ gene in the parotid gland were successfully produced by somatic cell nuclear transfer technology. The ADTZ activity in saliva of 6 transgenic pigs was found to be 7.11 ± 2.63 U/mL. The feeding trial with aflatoxin (AFT) results showed that there were significant difference about the serum biochemical index such as total protein (TP), albumin (ALB), globulin (GLB) contents and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity and AFT residues in serum and liver between the pigs in the test treatment (transgenic pigs) producing ADTZ and those in the positive control (P < 0.05). In order to investigate the inheritance of the transgene, 11 G1 transgenic pigs were successfully obtained. The ADTZ activity in saliva of 11 G1 transgenic pigs was found to be 5.82 ± 1.53 U/mL. The feeding trial with AFT results showed that the serum biochemical index containing TP, ALB and GLB contents and ALT and AST activity and AFB1 residues in serum and liver of the pigs in the test treatment (transgenic pigs) producing ADTZ were significantly different than those in the positive control (P < 0.05). The above results demonstrated that ADTZ produced in transgenic pigs could improve the effect of the AFT contamination of feed on pigs.

Rationale: Airway smooth muscle (ASM) is the pivotal tissue regulating bronchomotor tone in asthma. Enhanced excitation-contraction (EC) coupling in human ASM (HASM) cells is the underlying mechanism of airway hyperresponsiveness (AHR) in asthma and obesity. HASM cells express an array of receptors that modulate EC coupling. We previously reported that HASM cells from obese donors show a hyperresponsive phenotype in vitro. Unbiased phosphoproteomic analysis of HASM cells from normal and obese donors identified CCK receptor (CCKR) signaling as a differentially modulated pathway in obesity. We hypothesized that CCK receptors differentially modulate excitation-contraction coupling in HASM cells from obese donors compared to that from non-obese donors. Methods: HASM cells obtained from age, sex and ethnic group-matched non-obese (BMI mean±SD: 23.0±1.0, n=5 donors) and obese (BMI mean±SD:43.0±9.7, n=5 donors) lung donors were used in these experiments. Expression of CCK receptor isoforms A and B were determined by qRT-PCR. Fluo-8-loaded HASM cells were stimulated with CCK (sulfated CCK-8, 0.1-10 nM) and time-dependent fluorescence was measured to determine cytosolic Ca 2+ ([Ca 2+ ] i) levels. Phosphorylation of myosin light chain (MLC) and paxilin were determined following 10 min exposure to CCK (0.1-10 nM) or histamine (1 uM). Results: CCK receptor A (CCKAR) mRNA levels were comparable between non-obese and obese donor-derived HASM cells (CCKAR/cyclophilin C t value ratio mean±SD: non-obese 1.29±0.06 Vs obese 1.29±0.13, n=3 donors/group). However, CCK receptor B (CCKBR) transcripts were undetectable in HASM cells. CCK (0.1-10 nM) elicited robustly increased cytosolic Ca 2+ in HASM cells, accompanied by increased MLC and paxilin phosphorylations.

Tai-hua Jin and An-gang Lou contributed equally to this work.

Yanbian yellow cattle breeding is limited by its slow growth. We previously found that the miRNA miR-6523a is differentially expressed between Yanbian yellow cattle and Han Yan cattle, which differ in growth characteristics. In this study, we evaluated the effects of miR-6523a on growth hormone (GH) secretion in pituitary cells of Yanbian yellow cattle. Bioinformatics analyses using TargetScan and RNAhybrid as well as dual luciferase reporter assays showed that miR-6523a targets the 3' UTR of SSTR5 (somatostatin receptor 5). We further found that the mRNA and protein expression levels of GH in pituitary cells were significantly higher in cells treated with miR-6523a mimic than in the control group (P=0.0082 and P=0.0069). GH mRNA and protein expression levels were lower in cells treated with miR-6523a inhibitor than in the control group, but the difference was not significant (P=0.064 and P=0.089). SSTR5 mRNA and protein levels were inhibited by miR-6523a mimic compared with the control group) (P=0.0024 and P=0.0028) and were elevated slightly by miR-6523a inhibitor (P=0.093 and P=0.091). These results prove that miR-6523a regulates GH secretion in pituitary cells by SSTR5. More broadly, these findings provide a basis for studies of the roles of miRNAs in animal growth and development.