scholarly journals Generation of heritable double muscle buttocks rabbits via myostatin mutation with CRISPR/Cas9 system

Author(s):  
Yu Zhang ◽  
Yalin Zheng ◽  
Liyan Wu ◽  
Zhipeng Li ◽  
Ning Xiao ◽  
...  

Abstract Background Myostatin (MSTN) is a member of the transforming growth factor (TGF-β) superfamily and is considered to be a negative regulator that inhibits muscle development and regeneration, inactivity of MSTN gene may affect the development and regeneration of muscle in a few of animals. Results In the present study, the muscle mass negative regulator gene myostatin (MSTN) was knocked out at two novel sits in exon3, and the function of these mutation was determined in the offspring rabbits. The typical double muscle phenotype with hyperplasia and hypertrophy of muscle fiber was observed in the MSTN KO rabbits, and similar phenotype was confirmed in the F1 generation rabbits. The body weight of MSTN-KO+/− rabbits 3708 ± 43.06 g were significant heavier at 180 days than that of control WT rabbit 3224 ± 48.64 g (P < 0.001). Fourteen litters of F1 generation rabbits were produced, and the mutation of MSTN could be stably inherited in the MSTN KO rabbits. Conclusions Heritable double muscle buttocks rabbits via myostatin mutation with CRISPR/Cas9 system were generated, which will be valuable in meat rabbits breeding and a useful animal model for the study of human muscle development related diseases.

2021 ◽  
Vol 12 ◽  
Author(s):  
Caroline Barbé ◽  
Audrey Loumaye ◽  
Pascale Lause ◽  
Olli Ritvos ◽  
Jean-Paul Thissen

Skeletal muscle, the most abundant tissue in the body, plays vital roles in locomotion and metabolism. Understanding the cellular processes that govern regulation of muscle mass and function represents an essential step in the development of therapeutic strategies for muscular disorders. Myostatin, a member of the TGF-β family, has been identified as a negative regulator of muscle development. Indeed, its inhibition induces an extensive skeletal muscle hypertrophy requiring the activation of Smad 1/5/8 and the Insulin/IGF-I signaling pathway, but whether other molecular mechanisms are involved in this process remains to be determined. Using transcriptomic data from various Myostatin inhibition models, we identified Pak1 as a potential mediator of Myostatin action on skeletal muscle mass. Our results show that muscle PAK1 levels are systematically increased in response to Myostatin inhibition, parallel to skeletal muscle mass, regardless of the Myostatin inhibition model. Using Pak1 knockout mice, we investigated the role of Pak1 in the skeletal muscle hypertrophy induced by different approaches of Myostatin inhibition. Our findings show that Pak1 deletion does not impede the skeletal muscle hypertrophy magnitude in response to Myostatin inhibition. Therefore, Pak1 is permissive for the skeletal muscle mass increase caused by Myostatin inhibition.


2005 ◽  
Vol 33 (6) ◽  
pp. 1513-1517 ◽  
Author(s):  
F.S. Walsh ◽  
A.J. Celeste

Myostatin, or GDF-8 (growth and differentiation factor-8), was first identified through sequence identity with members of the BMP (bone morphogenetic protein)/TGF-β (transforming growth factor-β) superfamily. The skeletal-muscle-specific expression pattern of myostatin suggested a role in muscle development. Mice with a targeted deletion of the myostatin gene exhibit a hypermuscular phenotype. In addition, inactivating mutations in the myostatin gene have been identified in ‘double muscled’ cattle breeds, such as the Belgian Blue and Piedmontese, as well as in a hypermuscular child. These findings define myostatin as a negative regulator of skeletal-muscle development. Myostatin binds with high affinity to the receptor serine threonine kinase ActRIIB (activin type IIB receptor), which initiates signalling through a smad2/3-dependent pathway. In an effort to validate myostatin as a therapeutic target in a post-embryonic setting, a neutralizing antibody was developed by screening for inhibition of myostatin binding to ActRIIB. Administration of this antimyostatin antibody to adult mice resulted in a significant increase in both muscle mass and functional strength. Importantly, similar results were obtained in a murine model of muscular dystrophy, the mdx mouse. Unlike the myostatin-deficient animals, which exhibit both muscle hypertrophy and hyperplasia, the antibody-treated mice demonstrate increased musculature through a hypertrophic mechanism. These results validate myostatin inhibition as a therapeutic approach to muscle wasting diseases such as muscular dystrophy, sarcopenic frailty of the elderly and amylotrophic lateral sclerosis.


2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Shengwei Hu ◽  
Chuangfu Chen ◽  
Jingliang Sheng ◽  
Yufang Sun ◽  
Xudong Cao ◽  
...  

Myostatin is a member of the transforming growth factor beta (TGF-β) superfamily that functions as a negative regulator of skeletal muscle development and growth. Myostatin blockade therefore offers a strategy for promoting muscle growth in livestock production without resorting to genetic manipulation. In this report, we examined the effect of myostatin inhibition by plasmid-mediated delivery of a mutant myostatin propeptide (MProD76A), a natural inhibitor of myostatin, on the growth performance of mice. A significant increase in skeletal muscle mass was observed after a single intramuscular injection of naked plasmid DNA encoding MProD76A into mice. Enhanced muscle growth occurred because of myofiber hypertrophy, but no cardiac muscle hypertrophy and organomegaly was observed in the mice after myostatin inhibition by plasmid-mediated MProD76A delivery. These results demonstrate a promising approach to enhancing muscle growth that warrants further investigation in domestic animals.


Genetics ◽  
1994 ◽  
Vol 137 (2) ◽  
pp. 483-498
Author(s):  
J Ahnn ◽  
A Fire

Abstract We have used available chromosomal deficiencies to screen for genetic loci whose zygotic expression is required for formation of body-wall muscle cells during embryogenesis in Caenorhabditis elegans. To test for muscle cell differentiation we have assayed for both contractile function and the expression of muscle-specific structural proteins. Monoclonal antibodies directed against two myosin heavy chain isoforms, the products of the unc-54 and myo-3 genes, were used to detect body-wall muscle differentiation. We have screened 77 deficiencies, covering approximately 72% of the genome. Deficiency homozygotes in most cases stain with antibodies to the body-wall muscle myosins and in many cases muscle contractile function is observed. We have identified two regions showing distinct defects in myosin heavy chain gene expression. Embryos homozygous for deficiencies removing the left tip of chromosome V fail to accumulate the myo-3 and unc-54 products, but express antigens characteristic of hypodermal, pharyngeal and neural development. Embryos lacking a large region on chromosome III accumulate the unc-54 product but not the myo-3 product. We conclude that there exist only a small number of loci whose zygotic expression is uniquely required for adoption of a muscle cell fate.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Katharina Metzger ◽  
Dirk Dannenberger ◽  
Armin Tuchscherer ◽  
Siriluck Ponsuksili ◽  
Claudia Kalbe

Abstract Background Climate change and the associated risk for the occurrence of extreme temperature events or permanent changes in ambient temperature are important in the husbandry of farm animals. The aim of our study was to investigate the effects of permanent cultivation temperatures below (35 °C) and above (39 °C, 41 °C) the standard cultivation temperature (37 °C) on porcine muscle development. Therefore, we used our porcine primary muscle cell culture derived from satellite cells as an in vitro model. Neonatal piglets have limited thermoregulatory stability, and several days after birth are required to maintain their body temperature. To consider this developmental step, we used myoblasts originating from thermolabile (five days of age) and thermostable piglets (twenty days of age). Results The efficiency of myoblast proliferation using real-time monitoring via electrical impedance was comparable at all temperatures with no difference in the cell index, slope or doubling time. Both temperatures of 37 °C and 39 °C led to similar biochemical growth properties and cell viability. Only differences in the mRNA expression of myogenesis-associated genes were found at 39 °C compared to 37 °C with less MYF5, MYOD and MSTN and more MYH3 mRNA. Myoblasts grown at 35 °C are smaller, exhibit higher DNA synthesis and express higher amounts of the satellite cell marker PAX7, muscle growth inhibitor MSTN and metabolic coactivator PPARGC1A. Only permanent cultivation at 41 °C resulted in higher HSP expression at the mRNA and protein levels. Interactions between the temperature and donor age showed that MYOD, MYOG, MYH3 and SMPX mRNAs were temperature-dependently expressed in myoblasts of thermolabile but not thermostable piglets. Conclusions We conclude that 37 °C to 39 °C is the best physiological temperature range for adequate porcine myoblast development. Corresponding to the body temperatures of piglets, it is therefore possible to culture primary muscle cells at 39 °C. Only the highest temperature of 41 °C acts as a thermal stressor for myoblasts with increased HSP expression, but it also accelerates myogenic development. Cultivation at 35 °C, however, leads to less differentiated myoblasts with distinct thermogenetic activity. The adaptive behavior of derived primary muscle cells to different cultivation temperatures seems to be determined by the thermoregulatory stability of the donor piglets.


Author(s):  
Yiping Hu ◽  
Juan He ◽  
Lianhua He ◽  
Bihua Xu ◽  
Qingwen Wang

AbstractTransforming growth factor-β (TGF-β) plays a critical role in the pathological processes of various diseases. However, the signaling mechanism of TGF-β in the pathological response remains largely unclear. In this review, we discuss advances in research of Smad7, a member of the I-Smads family and a negative regulator of TGF-β signaling, and mainly review the expression and its function in diseases. Smad7 inhibits the activation of the NF-κB and TGF-β signaling pathways and plays a pivotal role in the prevention and treatment of various diseases. Specifically, Smad7 can not only attenuate growth inhibition, fibrosis, apoptosis, inflammation, and inflammatory T cell differentiation, but also promotes epithelial cells migration or disease development. In this review, we aim to summarize the various biological functions of Smad7 in autoimmune diseases, inflammatory diseases, cancers, and kidney diseases, focusing on the molecular mechanisms of the transcriptional and posttranscriptional regulation of Smad7.


PPAR Research ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Allan Ramirez ◽  
Erin N. Ballard ◽  
Jesse Roman

Transforming growth factorβ1 (TGFβ1) promotes fibrosis by, among other mechanisms, activating quiescent fibroblasts into myofibroblasts and increasing the expression of extracellular matrices. Recent work suggests that peroxisome proliferator-activated receptorγ(PPARγ) is a negative regulator of TGFβ1-induced fibrotic events. We, however, hypothesized that antifibrotic pathways mediated by PPARγare influenced by TGFβ1, causing an imbalance towards fibrogenesis. Consistent with this, primary murine primary lung fibroblasts responded to TGFβ1 with a sustained downregulation of PPARγtranscripts. This effect was dampened in lung fibroblasts deficient in Smad3, a transcription factor that mediates many of the effects of TGFβ1. Paradoxically, TGFβ1 stimulated the activation of the PPARγgene promoter and induced the phosphorylation of PPARγin primary lung fibroblasts. The ability of TGFβ1 to modulate the transcriptional activity of PPARγwas then tested in NIH/3T3 fibroblasts containing a PPARγ-responsive luciferase reporter. In these cells, stimulation of TGFβ1 signals with a constitutively active TGFβ1 receptor transgene blunted PPARγ-dependent reporter expression induced by troglitazone, a PPARγactivator. Overexpression of PPARγprevented TGFβ1 repression of troglitazone-induced PPARγ-dependent gene transcription, whereas coexpression of PPARγand Smad3 transgenes recapitulated the TGFβ1 effects. We conclude that modulation of PPARγis controlled by TGFβ1, in part through Smad3 signals, involving regulation of PPARγexpression and transcriptional potential.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tali Leibovich-Raveh ◽  
Ashael Raveh ◽  
Dana Vilker ◽  
Shai Gabay

AbstractWe make magnitude-related decisions every day, for example, to choose the shortest queue at the grocery store. When making such decisions, which magnitudes do we consider? The dominant theory suggests that our focus is on numerical quantity, i.e., the number of items in a set. This theory leads to quantity-focused research suggesting that discriminating quantities is automatic, innate, and is the basis for mathematical abilities in humans. Another theory suggests, instead, that non-numerical magnitudes, such as the total area of the compared items, are usually what humans rely on, and numerical quantity is used only when required. Since wild animals must make quick magnitude-related decisions to eat, seek shelter, survive, and procreate, studying which magnitudes animals spontaneously use in magnitude-related decisions is a good way to study the relative primacy of numerical quantity versus non-numerical magnitudes. We asked whether, in an animal model, the influence of non-numerical magnitudes on performance in a spontaneous magnitude comparison task is modulated by the number of non-numerical magnitudes that positively correlate with numerical quantity. Our animal model was the Archerfish, a fish that, in the wild, hunts insects by shooting a jet of water at them. These fish were trained to shoot water at artificial targets presented on a computer screen above the water tank. We tested the Archerfish's performance in spontaneous, untrained two-choice magnitude decisions. We found that the fish tended to select the group containing larger non-numerical magnitudes and smaller quantities of dots. The fish selected the group containing more dots mostly when the quantity of the dots was positively correlated with all five different non-numerical magnitudes. The current study adds to the body of studies providing direct evidence that in some cases animals’ magnitude-related decisions are more affected by non-numerical magnitudes than by numerical quantity, putting doubt on the claims that numerical quantity perception is the most basic building block of mathematical abilities.


2018 ◽  
Vol 19 (11) ◽  
pp. 3672 ◽  
Author(s):  
Yutaro Tsubakihara ◽  
Aristidis Moustakas

Metastasis of tumor cells from primary sites of malignancy to neighboring stromal tissue or distant localities entails in several instances, but not in every case, the epithelial-mesenchymal transition (EMT). EMT weakens the strong adhesion forces between differentiated epithelial cells so that carcinoma cells can achieve solitary or collective motility, which makes the EMT an intuitive mechanism for the initiation of tumor metastasis. EMT initiates after primary oncogenic events lead to secondary secretion of cytokines. The interaction between tumor-secreted cytokines and oncogenic stimuli facilitates EMT progression. A classic case of this mechanism is the cooperation between oncogenic Ras and the transforming growth factor β (TGFβ). The power of TGFβ to mediate EMT during metastasis depends on versatile signaling crosstalk and on the regulation of successive waves of expression of many other cytokines and the progressive remodeling of the extracellular matrix that facilitates motility through basement membranes. Since metastasis involves many organs in the body, whereas EMT affects carcinoma cell differentiation locally, it has frequently been debated whether EMT truly contributes to metastasis. Despite controversies, studies of circulating tumor cells, studies of acquired chemoresistance by metastatic cells, and several (but not all) metastatic animal models, support a link between EMT and metastasis, with TGFβ, often being a common denominator in this link. This article aims at discussing mechanistic cases where TGFβ signaling and EMT facilitate tumor cell dissemination.


2008 ◽  
Vol 78 (1) ◽  
pp. 131-137 ◽  
Author(s):  
Francisco E. Nicolás-Molina ◽  
Eusebio Navarro ◽  
Rosa M. Ruiz-Vázquez

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