Project description:We performed transcriptome analysis of the longissimus dorsi (LD) muscle during four development stages (60, 120, 240 and 400 days after birth) in Laiwu pigs, an indigenous fatty pig breed in North China. This study provides a reference for exploring transcriptome regulation mechanisms affecting muscle growth and development in obese pigs.
Project description:Microarrays were used for transcription profiling of skeletal muscle samples taken at birth, when the phenotype was not expressed, and 12 weeks of age from Callipyge and wild type sheep. The genes that underlie the expression of the phenotype rather than result from the fibre type change in the affected muscle have been identified. We used microarrays to detail the global programme of gene expression underlying the hypertrophy phenotype and identified distinct classes of regulated genes during this process. A working model that links the muscle hypertrophy phenotype with a core group of transcriptional coregulators is proposed. Experiment Overall Design: Gene expression analyses were performed primarily on longissimus dorsi skeletal muscle (LD) from Wild type (NN) and Callipyge (NCpat) sheep using Bovine Affymetrix GeneChip microarrays. Two developmental time-points were investigated in this study: newborn (within 5 days of birth; T0) and 11-12 weeks post-birth (T12). The muscle hypertrophy phenotype developed over the first 2-3 months and was associated with a significant change in muscle fibre type (Carpenter et al., 1996; Cockett et al., 1994; 1996; Kerth et al., 2003). One of the objectives of the gene expression analysis was to delineate between those genes that underlie the muscle hypertrophy in Callipyge sheep and those that result from the fibre type change in the affected muscle. To address this issue a comparison was undertaken of gene expression in wild type skeletal muscles with differing fibre type compositions to identify fibre type specific genes. These samples were taken from NN animals at T12. The three skeletal muscles used in this analysis were semimembranosis (SM), semitendinosis (ST) and longissimus dorsi (LD).
Project description:To investigate the impact of adding succinate to the diet on the production performance, meat quality, muscle fiber characteristics, and transcriptome of the longissimus dorsi muscle in Tan sheep, 36 Tan sheep were selected and fed with different levels of succinate (0%, 0.5%, 1.0%, 2.0%) for a 60-day trial period. Overall, compared to the control group, the addition of succinate to the diet improved the production performance, slaughter performance, and meat quality of Tan sheep. It significantly increased dry matter intake, carcass weight, eye muscle area, and the GR value while significantly reducing the shear force and cooking loss of the longissimus dorsi muscle (p<0.05). Furthermore, the addition of succinate to the diet altered the muscle fiber characteristics of the longissimus dorsi muscle in Tan sheep, significantly increasing the fiber diameter and cross-sectional area of type I and type IIa muscle fibers (p<0.05). The addition of 1.0% succinate to the diet altered the transcriptome of the longissimus dorsi muscle in Tan sheep, with 741 differentially expressed genes identified compared to the control group. These differentially expressed genes were involved in various pathways related to lipid metabolism, energy metabolism, and muscle development, such as insulin secretion, insulin resistance, cAMP signaling pathway, PI3K-Akt signaling pathway, and FoxO signaling, among others. In summary, succinate plays a crucial role in regulating energy metabolism, protein deposition, and glucose and lipid metabolism homeostasis in Tan sheep through insulin signaling pathways and the interaction of muscle cell factors. By modulating the expression of relevant genes, succinate improves the muscle fiber characteristics of Tan sheep, thereby enhancing production performance and meat quality.
Project description:We have completed the high quality reference genome for domestic sheep (Oar v3.1) and performed a detailed survey of gene expression across different tissues. RNA-seq data of 7 tissue types from the reference female Texel and skin tissue from a Gansu alpine fine wool sheep were sequenced.
Project description:Expression data from Sheep longissimus dorsi (LD) muscle during development; fetal lambs (80, 100, 120 days gestation), new born lambs at birth (150 d) and lambs at 12 weeks (230 d) The fetal to neonatal developmental transition corresponds with profound changes in skeletal muscle function as it adapts to the new physiological demands of locomotion and postural support against gravity. The mechanisms underpinning this adaption process are unclear but are likely to be initiated by changes in hormone levels occurring during the major developmental transition. We tested the hypothesis that this period is associated with changes in the transcription of skeletal muscle genes, particularly genes involved in oxidative metabolism. Using an ovine model, transcriptional profiling was performed on longissimus dorsi skeletal muscle taken at three fetal developmental time points (80, 100 and 120 d of fetal development) as well as two postnatal time points, one within 3 days after birth and a second at 12 weeks of age. The developmental time course was dominated by large changes in the expression of 2471 genes during the period from late fetal development (120 d fetal development) to birth (within 1-3 days of birth). Analysis of the functions of the genes that were uniquely up-regulated in this period showed strong enrichment for oxidative metabolism and the TCA cycle indicating enhanced mitochondrial activity. Indeed, histological examination of tissues from these developmental time points directly demonstrated a marked increase in mitochondrial activity between the late fetal and early post-natal samples. The genes that were down-regulated in this period suggested de-emphasis of an array of biological functions including Wnt signaling, cell adhesion and differentiation. There were also changes in the expression of genes prior to this late fetal â postnatal transition and between the two postnatal time points that involved a variety of biological functions. It is concluded that there is substantial and coordinated changes in the transcription of a large number of genes in skeletal muscle which underpin the adaption of muscle to the new physiological demands in the postnatal environment. Microarrays were used for transcription profiling of skeletal muscle samples taken from fetal lambs (80, 100, 120 days gestation), new born lambs at birth (150 d) and lambs at 12 weeks (230 d) Sheep used in this experiment were bred from a research flock of Dorset/Suffolk/Rambouillet cross-bred sheep raised at Utah State University and cared for and euthanased for sample collection in accordance with the animal ethics guidelines of Utah State University (Utah, USA). Longissimus dorsi (LD) skeletal muscle samples were taken from fetal lambs at 80, 100 and 120 days of gestation, new born lambs within 1 to 3 days of birth (i.e. 150 days of development) and young lambs at 12 weeks of age (230 days of development). Three individuals were sampled at each developmental time
Project description:We have completed the high quality reference genome for domestic sheep (Oar v3.1) and performed a detailed survey of gene expression across different tissues. RNA-seq data of 7 tissue types from the reference female Texel and skin tissue from a Gansu alpine fine wool sheep were sequenced. Here is the part of the RNA-seq data sequenced in BGI, including 7 tissue types from the reference female Texel and skin type from a Gansu alpine fine wool sheep.
Project description:We have completed the high quality reference genome for domestic sheep (Oar v3.1). Early-stage Illumina GA sequence platform sequenced less reads in high GC content regions than in other regions. To read through higher GC content regions, we generated 2 Gb MeDIP-seq data for filling gaps in sheep reference genome assembly.