TET Family Members Are Integral to Porcine Oocyte Maturation and Parthenogenetic Pre-Implantation Embryogenesis.

The ten-eleven translocation (TET) enzyme family, which includes TET1/2/3, participates in active DNA demethylation in the eukaryotic genome; moreover, TET1/2/3 are functionally redundant in mice embryos. However, the combined effect of TET1/2/3 triple-gene knockdown or knockout on the porcine oocytes or embryos is still unclear. In this study, using Bobcat339, a specific small-molecule inhibitor of the TET family, we explored the effects of TET enzymes on oocyte maturation and early embryogenesis in pigs.

Dual single guide RNAs-mediating deletion of mature myostatin peptide results in concomitant muscle fibre hyperplasia and adipocyte hypotrophy in pigs.

Myostatin (MSTN) is a major gene target for skeletal muscle overgrowth in animals. We hypothesized that deletion of the entire mature peptide encoded by MSTN in pigs would knock out its bioactive form and accordingly stimulate skeletal muscle overgrowth. Thus, we engineered two pairs of single-guide RNAs (sgRNAs) to target exons 1 and 3 of MSTN in primary fetal fibroblasts of Taoyuan black pigs.

Myostatin increases the expression of matrix metalloproteinase genes to promote preadipocytes differentiation in pigs.

ABSTACTMyostatin (MSTN) resulted in reduced backfat thickness in MSTN-knockout (MSTN-KO) pigs, whereas the underlying mechanism remains elusive. In this study, RNA sequencing (RNA-seq) was used to screen differentially expressed genes (DEGs) in porcine fat tissues. We identified 285 DEGs, including 4 adipocyte differentiation-related genes (ADRGs).

ACSL4 Directs Intramuscular Adipogenesis and Fatty Acid Composition in Pigs.

The intramuscular fat is a major quality trait of meat, affecting sensory attributes such as flavor and texture. Several previous GWAS studies identified Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) gene as the candidate gene to regulate intramuscular fat content in different pig populations, but the underlying molecular function of ACSL4 in adipogenesis within pig skeletal muscle is not fully investigated. In this study, we isolated porcine endogenous intramuscular adipocyte progenitors and performed ACSL4 loss- and gain-of-function experiments during adipogenic differentiation.

Myostatin regulates fatty acid desaturation and fat deposition through MEF2C/miR222/SCD5 cascade in pigs.

Myostatin (MSTN), associated with the "double muscling" phenotype, affects muscle growth and fat deposition in animals, whereas how MSTN affects adipogenesis remains to be discovered. Here we show that MSTN can act through the MEF2C/miR222/SCD5 cascade to regulate fatty acid metabolism. We generated MSTN-knockout (KO) cloned Meishan pigs, which exhibits typical double muscling trait.

Generation of Acsl4 Gene Knockout Mouse Model by CRISPR/Cas9-Mediated Genome Engineering.

Acyl-CoA synthetase 4 (Acsl4) is involved in lipid synthesis and fatty acid degradation, and disruption of its function causes lipid metabolism disorder in various species. Herein, we report the generation of Acsl4 knockout (KO) mice using the CRISPR/Cas9 gene editing system to study its effects on lipid deposition. In this report, a large 12kb deletion in the Acsl4 gene was performed by coinjection of Cas9 mRNA and two guide RNAs (sgRNAs) into mouse fertilized oocytes.

ФC31 Integrase-Mediated Isolation and Characterization of Novel Safe Harbors for Transgene Expression in the Pig Genome.

Programmable nucleases have allowed the rapid development of gene editing and transgenics, but the technology still suffers from the lack of predefined genetic loci for reliable transgene expression and maintenance. To address this issue, we used ФC31 integrase to navigate the porcine genome and identify the pseudo attP sites suitable as safe harbors for sustained transgene expression. The combined ФC31 integrase mRNA and an enhanced green fluorescence protein (EGFP) reporter donor were microinjected into one-cell zygotes for transgene integration.

CRISPR/Cas9-mediated ApoE-/- and LDLR-/- double gene knockout in pigs elevates serum LDL-C and TC levels.

The traditional method to establish a cardiovascular disease model induced by high fat and high cholesterol diets is time consuming and laborious and may not be appropriate in all circumstances. A suitable pig model to study metabolic disorders and subsequent atherosclerosis is not currently available. For this purpose, we applied the CRISPR/Cas9 system to Bama minipigs, targeting apolipoprotein E (ApoE) and low density lipoprotein receptor (LDLR) gene simultaneously.

Isozygous and selectable marker-free MSTN knockout cloned pigs generated by the combined use of CRISPR/Cas9 and Cre/LoxP.

Predictable, clean genetic modification (GM) in livestock is important for reliable phenotyping and biosafety. Here we reported the generation of isozygous, functional myostatin (MSTN) knockout cloned pigs free of selectable marker gene (SMG) by CRISPR/Cas9 and Cre/LoxP. CRISPR/Cas9-mediated homologous recombination (HR) was exploited to knock out (KO) one allele of MSTN in pig primary cells.

Pseudo attP sites in favor of transgene integration and expression in cultured porcine cells identified by Streptomyces phage phiC31 integrase.

Phage PhiC31 integrase integrates attB-containing plasmid into pseudo attP site in eukaryotic genomes in a unidirectional site-specific manner and maintains robust transgene expression. Few studies, however, explore its potential in livestock. This study aims to discover the molecular basis of PhiC31 integrase-mediated site-specific recombination in pig cells.

An asymmetric PCR-based, reliable and rapid single-tube native DNA engineering strategy.

Background: Widely used restriction-dependent cloning methods are labour-intensive and time-consuming, while several types of ligase-independent cloning approaches have inherent limitations. A rapid and reliable method of cloning native DNA sequences into desired plasmids are highly desired.

Results: This paper introduces ABI-REC, a novel strategy combining asymmetric bridge PCR with intramolecular homologous recombination in bacteria for native DNA cloning.