Project description:The experiment aimed at studying gene expression differences in longissimus dorsi muscle from pigs from two groups: High versus low intramuscular fat (IMF). The animals were selected from a crossbred population of Landrace x Yorkshire/Landrace x Duroc animals, where we have previously found a highly significant QTL for IMF (Grindflek et al. 2001: "Detection of quantitative trait loci for meat quality in a commercial slaughter pig cross", Mammalian Genome 12(4): 299-304), and by microarray analysis we hoped to identify candidate genes for the QTL and/or pathways that are affected by the genes responsible for the QTL. Keywords: phenotype comparison Direct dye-swap design, with 14 animals in each group (high IMF and low IMF) on 14 separate arrays
Project description:The experiment aimed at studying gene expression differences in longissimus dorsi muscle from pigs from two groups: High versus low intramuscular fat (IMF). The animals were selected from a crossbred population of Landrace x Yorkshire/Landrace x Duroc animals, where we have previously found a highly significant QTL for IMF (Grindflek et al. 2001: "Detection of quantitative trait loci for meat quality in a commercial slaughter pig cross", Mammalian Genome 12(4): 299-304), and by microarray analysis we hoped to identify candidate genes for the QTL and/or pathways that are affected by the genes responsible for the QTL. Keywords: phenotype comparison
Project description:The Laiwu pig is famous for its excessively higher level of IMF content, however, the exact regulatory mechanism is still unknown. The intramuscular fat content (IMF) is an economically important traits in pigs, which is controlled by multiple genes and biological pathways. In the present study, we performed an integrated transcriptome-assisted label-free quantitative proteomic analysis of longissimus dorsi (LD) muscle in Laiwu pigs at the fastest IMF deposition stage. A total of 5074 unique proteins were identified and 191 were differentially abundant proteins (DAPs) (> 1.2-fold cutoff, p < 0.05), which were hierarchically clustered in the LD muscle over two developmental stages from 120 d to 240 d. Proteins participating in the regulation of lipolysis in adipocytes and AMPK signaling pathway were identified. Six proteins were analyzed using parallel reaction monitoring (PRM) to confirm the reliability of the TMT proteomic analysis. Association networks of differentially abundant proteins revealed that these DAPs were mainly involved in ribosome biosynthesis in eukaryotic species. A comparasion between transcriptomic (mRNA) and proteomic data revealed seven differentially expressed genes corresponding to DAPs. This study, for the first time, provides some data for the elucidation of the molecular mechanism of IMF deposition in pigs.
Project description:Low protein diets supplied during the growing period of pigs can diminish their growth rate and increase the intramuscular fat (IMF) content which affects the sensorial and technological characteristics of the traits. In the present study, the effects of a low protein diet supplied during the growing diet of Duroc x Iberian crossbred pigs on several phenotypic traits and liver and longissimus dorsi transcriptome, were analysed 20 days after the differential treatment was started (EARLY) and at the end of it (FINAL). A total of 20 crossbred pigs were assigned to two different dietary treatments during the growing period: a control diet (C) and a low protein diet (LP) with the same energy and lower levels of raw protein (11%) and lysine (0.60%). The transcriptomes of liver and longissimus dorsi were quantified through RNAseq. A total of 134 differentially expressed annotated genes and new isoforms (DEGs) between C and LP diets in liver of EARLY animals; 480 DEGs in liver of LATE animals, and 128 DEGs and 68 DEGs in longissimus dorsi of EARLY and LATE animals were detected. The functional analyses revealed that low protein diet diminishes the expression in liver of genes codifying for proteins involved in immune system both in EARLY and LATE animals, affects the expression of genes involved in cholesterol homeostasis in liver and in the energy process and growth in longissimus dorsi. Pigs fed with LP diet had not higher IMF content than C ones, although some lipogenesis genes such as FASN, SCD or SREBF1 were higher expressed on their liver. A low protein diet supplied during growing period affects multiple biological process that could compromise the immune and energy state of the Duroc x Iberian crossbred pigs. These results point out that we should be very cautious before implementing this type of regime in Duroc x Iberian pigs.
Project description:Background: Intramuscular fat (IMF) content is highly valued as it improves meat product quality by enhancing taste, juiciness, and tenderness. IMF content can be significantly different between breeds. Thought many lipid metabolism-related genes are stated to be associated with IMF deposition, the molecular mechanism of IMF deposition is still poorly understood. To date, no gene or mutation loci responsible for the difference of IMF content among cattle breeds has been identified. To identify transcripts with potential regulatory role in lipid accumulated in muscle tissue, RNA sequencing was performed to compare the mRNAs, lncRNAs, and circRNAs expression patterns in the longissimus dorsi muscle and back fat between Chinese buffalo and cattle. Results: A total of 12 cDNA libraries were constructed. A total of 925,441,106 and 512,507,068 raw reads were obtained from buffalo and cattle, respectively. After filtering the adaptor and low quality reads, 909,040,352 and 491,967,820 clean reads were retained. In total, 19,917 mRNAs, 43,975 lncRNAs, and 10,701 circRNAs were identified in buffalo and 19,383 mRNAs, 8,265 lncRNAs, and 18,535 circRNAs were identified in cattle.
Project description:10 + 10 Holstein x Charolais F2 cattle were assigned to 2 groups with high and low IMF content, respectively; Musculus longissimus dorsi mRNA expression was determined by microarray analysis
Project description:To further characterize genomic regions previously identified which are linked with meat quality traits like drip loss, PH, conductivity and etc., we employed a customary regional tiling array experiment for two pig populations. Total RNA were taken from muscle sample of M. longissimus dorsi of pigs selected from two phenotypic groups graded according to high (HI) and low (LO) drip loss. Hybridization were made in batches, 2 to 3 biological replicates for each sample. DuPi and PiF1 are code names for the two experimental populations. Total RNA were taken from muscle sample of M. longissimus dorsi of pigs selected from two phenotypic groups graded according to high (HI) and low (LO) drip loss. Hybridization were made in batches, 2 to 3 biological replicates for each sample.