Animal Biotechnology最新文献

The pig industry is an important component of Chinese agriculture. Chinese indigenous and Western commercial pig breeds provide valuable genetic resources for sustainable development of the pig industry, and selective signal analysis can advance our understanding of artificial and natural selective processes. In this study, we used whole genome re-sequencing data to analyze selection signatures in 43 Danish Large White [LW] pigs and 60 Chinese indigenous pigs (24 Anqing six-end white [AQ], 6 Asian wild [SS] pigs, 15 Diqing Tibetan [DQZ], and 15 Diannan small-ear [DN] pigs). We employed two calculation methods (F_ST and π ratio) to identify the selection signals of LW and Chinese indigenous pigs (top 1%). Among the selective sweep regions, 15 and 117 candidate genes were identified in Chinese indigenous pigs and LW pigs, respectively. The PIK3IP1, TUG1, and SELENOM genes were related to environmental adaptation in Chinese indigenous pigs; ALDH1A2, APC2, PTBP1, APQ9, and FGF7 were related to reproductive performance in LW pigs. Our findings provide insights into the genetic basis of economic traits of LW and Chinese indigenous pigs and offer a useful reference for future pig breeding and production.

m6A methylation is the most common mRNA modification in mammals and plays a significant role in regulating various biological functions. Some studies have demonstrated that the methyltransferase METTL3 can promote adipogenesis. However, the regulatory mechanisms of METTL14 and WTAP, both methyltransferases, in adipogenesis remain unclear. This study investigated their effects on bovine preadipocyte differentiation using siRNA-mediated knockdown combined with transcriptomic analysis. Silencing METTL14 and WTAP significantly impaired lipid droplet formation and revealed distinct regulatory pathways: METTL14 knockdown affected genes like JAK2 and STAT3, while WTAP suppression down-regulated PPARγ/FABP4 signalling pathway components. These findings demonstrate that WTAP specifically modulates bovine adipocyte differentiation through the PPARγ/FABP4 pathway.

The advancement of genetic engineering in chickens has enabled significant advancement in developmental biology, bioreactors, and disease resilience. The development of CRISPR/Cas9 genome engineering technology has further expanded the potential applications of genetic engineering in poultry. In this study we aimed to evaluate the efficacy of a direct in vivo transfection method, previously demonstrated to produce transgenic chickens, in generating gene knockout (KO) chickens. Specifically, we targeted the Interferon-α/β Receptor 1 (IFNAR1) and Interleukin 1 receptor, type I (IL1R1), both critical pathways in the inflammatory and antiviral responses. We designed guide RNAs targeting the genes and validated their efficiency in vivo via microinjection into the developing embryos. PCR analysis confirmed the presence of gene deletions in chimeric roosters, which were subsequently bred to produce G1 germline heterozygote KO offspring. Homozygous KO chickens were generated and subjected to phenotypic and functional analyses. Our results demonstrated successful generation of functional knockouts of both IFNAR1 and IL1R1 using a direct in vivo transfection. Overall, this study demonstrates that direct in vivo transfection provides a robust and predictable method for generating KO chickens, facilitating further research into avian immune responses and the development of antiviral strategies.

Egg weight is a primary economic trait in poultry breeding. Putian Black duck, an excellent local laying duck breed in Fujian Province, includes two different strains, black feather strain and white feather strain. The white feather strain of Putian Black duck is also known as Putian White duck. Except for the different feather colors, these two strains differ in egg weight. In this study, whole-genome resequencing was conducted on Putian Black duck and Putian White duck to explore the differences in the genetic mechanism of egg weight. LRP8, VLDLR, and LPL were identified as key candidate genes affecting egg weight. Mass spectrometry was used to detect the SNPs of LRP8, VLDLR, and LPL. Result indicates that the SNPs of LRP8, VLDLR, and LPL in both populations exhibited moderate polymorphism, and Putian Black duck possessed higher genetic variation and potential selectivity. Association analysis indicated that in Putian Black duck, four SNPs in the LRP8 gene were significantly associated with egg weight. These loci can be used as molecular markers for improving egg weight in Putian Black duck.

Ketosis is a common metabolic disease in high-yield dairy cows. Key genes affecting ketosis need to be further explored by new methods. The gene expression profiling and clinical data of GSE92398, GSE104079, and GSE4304 were obtained from the gene expression omnibus (GEO) database. Core modules and genes associated with RFI (residual feed intake) and ADF (alternate day fasting) were identified by weighted gene co-expression network analysis (WGCNA). Subsequently, the key genes related to ketosis and RFI were determined by protein-protein interaction (PPI) networks, ROC curves, functional enrichment, and differential expression analysis, respectively. The results showed that the genes of ACACA, ELOVL6 and XPO7 could be used as regulators of ketosis induced by low feed intake in dairy cows. At the same time, three genes (HRFI, STAT3 and IFNAR1) were retained as additional RFI biomarkers that could be considered. We identified three key factors as candidate genes and biomarkers of ketosis and RFI, respectively. These factors may provide a theoretical basis for targeted therapy of ketosis in dairy cows.

Variation in litter size (LS) in sheep is linked to genetic factors, including the Zona pellucida-3 (ZP3) gene, which plays a role in ovine reproductive processes. This study examined the association between ZP3 gene variations and LS in Kari sheep. Two groups of 160 Kari ewes were analysed: one consistently producing singletons and another producing twins, with occasional triplets. Additionally, Madakhlasht sheep, which sometimes produce twins, and Balkhi sheep, which produce only singletons, were used as references. The entire ZP3 gene was amplified using PCR and sequenced at 30× with Next Generation Sequencing. Bioinformatics analysis identified 70 variants across the three breeds, located in upstream regions, introns, and exons. Notably, two point mutations and a six-nucleotide insertion were found upstream of the initiation codon in twin-producing Kari ewes, potentially affecting ZP3 expression and LS. Two missense mutations (I101L in exon 1 and R408H in exon 8) were heterozygous in twin-producing Kari ewes but homozygous in other groups, correlating with LS. Protein modelling suggested that the I101L mutation alters the binding site, potentially impacting protein function. These findings indicate that ZP3 gene variations influence reproductive efficiency and LS in sheep, with specific variants serving as potential markers for selective breeding to enhance LS.

This study aims to establish an immortalized fibroblast cell line from Mongolian sheep. Primary Mongolian sheep fibroblasts (SSF) were isolated using tissue explant and enzymatic digestion methods, followed by microscopic observation, growth curve plotting, and karyotype analysis. The results confirmed the successful isolation of SSF. Human (hTERT) and sheep (sTERT) telomerase reverse transcriptase vectors were separately introduced into SSF, with cells passaged up to 36 generations following G418 selection. Microscopic examination and qRT-PCR results demonstrated that TERT transfection did not alter the morphology of SSF and led to stable, high levels of TERT expression (P < 0.01). Cell counting and flow cytometry revealed that TERT-transfected cells had higher viability and lower apoptosis rates compared to SSF (P < 0.05). Karyotype and soft agar colony formation assays indicated that hTERT and sTERT-transfected cells maintained normal characteristics without malignant transformation. β-galactosidase staining indicated that TERT transfection significantly reduced cellular senescence (P < 0.001). Additionally, sTERT-transfected cells exhibited higher TERT expression, enhanced viability, proliferation, and anti-senescence effects compared to hTERT-transfected cells (P < 0.05). In summary, the introduction of hTERT and sTERT effectively extends the lifespan of SSF, with sTERT demonstrating a more pronounced effect. This study provides critical evidence for preserving Mongolian sheep genetic resources and developing immortalized cell lines.

In order to study the distribution characteristics of intestinal microbiota and antibiotic resistance genes (ARGs) in Duzang pigs after adding stems and leaves of Panax notoginseng to the feed, the characteristics of intestinal microbiota were explored by metagenomic sequencing, and 14 ARGs and 2 integrase genes were detected by qPCR. The results showed that the addition of stems and leaves of P. notoginseng increased the relative abundance of Firmicutes, Lactobacillus and Pediococcus in the cecum of Duzang pigs. A total of 10 ARGs and 2 integrase genes were detected in the cecal contents of pigs. The addition of stems and leaves of P. notoginseng reduced the relative abundance of total ARGs, ermB, tetO and tetW in the cecum of Duzang pigs. The results of network analysis showed that multiple genera were potential hosts of ARGs. The addition of stems and leaves of P. notoginseng may reduce the relative abundance of ARGs by reducing the relative abundance of genera such as Corynebacterium and Flavonifractor, thereby reducing the risk of ARGs spread. This study provides a theoretical basis for the rational use of stems and leaves of P. notoginseng to control ARGs.

Insulin-like Growth Factor 2 mRNA-binding Protein 1 (IGF2BP1) is a candidate gene of significant interest for modulating economically important traits in livestock and poultry. The second intron of IGF2BP1 has been implicated in growth-related traits, though its precise mechanistic role remains elusive. Initial resequencing analyses in our laboratory indicated strong selective pressures on the IGF2BP1 genomic region, prompting the selection and identification of several single nucleotide polymorphisms (SNPs). Seven SNPs were mapped to the conserved region of the second intron, necessitating further investigation into their functional relevance and association with growth traits. In this study, 348 Nanjiang Yellow goats were analyzed, and the association analysis via the GLM program in SAS 9.4 identified five SNPs significantly correlated with growth traits. Notably, rs652062749(A > G) emerged as a critical locus influencing later-stage growth traits. Furthermore, strong linkage disequilibrium was observed among three SNPs, with the rs638185407 (T > A) variant markedly enhancing luciferase activity in H293T cells. Combination genotypes TTAACT, TTCCCC, and ATCACT were identified as superior for growth traits, offering theoretical insights for genetic co-breeding. This study underscores the potential utility of IGF2BP1 as a functional genetic marker in Nanjiang Yellow goat breeding programs.

Buffaloes are mono-ovulating animals, with only about 5% of primordial follicles being fully capable of maturation into primary oocytes throughout their reproductive years. In vitro primordial follicle activation technology provides a new way to manipulate and utilize oocyte resources. However, in vitro activation of buffalo primordial follicles has not been reported. In this study, buffalo cortical strips were cultured in vitro and activated with PI3K and mTOR stimulators, and the proportion of activated and developed follicles was evaluated and compared between groups . Furthermore, the key genes involved in primordial follicle activation were screened using RNA sequencing. Results showed that buffalo ovarian cortex can be well preserved by being cultured in vitro for at least 7 days and maintain its tissue properties and follicular morphology. In vitro, treatment with PI3K and mTOR pathway stimulators significantly enhanced the activation efficiency of the primordial follicles. In addition,  several differentially expressed genes related to follicular development, such as IDO1, CXCL10 and CXCL6 were significantly up-regulated after stimulation. Our findings demonstrate that PI3K and mTOR stimulators can significantly promote the activation and development of buffalo follicles, and providing technical support and a theoretical basis for the optimization of in vitro culture technology of buffalo preantral follicles .