肌生成抑素的研究现状

肌生成抑素(Myostatin,MSTN)是1997年发现的一种新的生长因子,是转化生长因子β(TGF-β)超家族的新成员,经研究发现其对骨骼肌的生长具有负调控作用,因此科学工作者将其命名为肌生成抑素。本文将对MSTN基因的定位、结构、功能、表达等方面进行阐述。1MSTN基因的定位和结构SongstegardTS.等对猪的MSTN基因进行染色体遗传图和物理图进行了研究,结果表明该基因位于15q2.3。到目前为止,已经至少对人、牛、猪的肌生成抑素基因的染色体定位进行了研究。LeeSJ.报道猪MSTNcDNA全部序列为1756bp,MSTN基因为6015bp,包括两个内含子和三…     

猪肌肉生长抑制素基因的研究进展

肌肉生长抑制素(MSTN)是骨骼肌生长发育的负调控因子。其活性的丧失或降低，会引起动物肌肉的过度发育，表现为双肌征状。最早在小鼠中发现该基因，随后通过荧光原位杂交法将猪MSTN基因定位于15q2.3上，进而分析了MSTN以及其分子结构，比较。MSTN基因在不同物种间的同源性。     

肌肉生成抑制素基因的研究

动物肌肉生成抑制素(Myostatin,MSTN)是Mcpherron等研究小鼠转化生长因子-β(TGF-β)超家族时发现的一种新的生长因子。当时命名为生长分化因子-β(GDF-β),后经研究发现,其对骨骼肌的生长具有负调控作用,因此改名为肌肉生成抑制素[1-3]。该基因编码的蛋白质对骨骼肌有负调控作用,动物缺乏MSTN时出现肌肉增大,骨骼肌肌群分布广,而且不增生脂肪等现象。MSTN主要在胚胎期的骨骼肌中表达,它的缺失使一些动物表现双肌性状[4-7]。1MSTN基因的发现及组织分布Mcpherron等(1997)根据TGF-β超家族的保守区设计一对简并引物,通过PCR扩增…     

动物肌生成抑制素基因的研究进展

肌生成抑制素(MSTN)基因是一种生长分化因子,表达产物主要调控骨骼肌生长发育。笔者介绍了该基因的特点、表达调控机理及其研究进展,并提出今后动物MSTN基因重要研究方向及意义。     

猪肌生成抑制素基因成熟蛋白编码序列表达载体的构建及其转录水平的检测

构建猪肌生成抑制素(MSTN)成熟蛋白编码序列的克隆与表达载体，并对mRNA进行转录水平的检测，为获得较好的猪肌生成抑制素抗原、制备抗体打下良好的基础。猪MSTN基因的cDNA去除信号肽后，用PCR扩增的1．2kb目的片段与pMDl8-T载体连接，将克隆载体的质粒DNA与同样用BamH Ⅰ和Sal Ⅰ限制性内切酶酶解的表达载体pET28a( )质粒定向连接，对筛选出的阳性克隆用酶切及测序法鉴定。对猪MSTN基因成熟蛋白编码序列进行反转录，对mRNA Northern杂交进行转录水平的检测。结果，所得到的序列与所设计的序列完全一致，表明成功地进行了猪MSTN基因编码序列的克隆及筛选；目的片段定向插入，阅读框架正确；RT-PCR成功地反转录得到约1．2kb的目的DNA片段，Northern杂交后对mRNA印迹放射自显影，见到清晰的1．2kb特异带。     

MSTN基因的研究进展

肌生成抑素(MSTN)是1997年发现的一种新的生长因子,其基因产物对骨骼肌的生长具有负调控作用,该基因缺失会导致骨骼肌增生.本文综述了MSTN基因的结构、在畜禽中的表达情况、作用机理以及研究意义.     

家畜肌生成抑制素基因的研究进展

肌生成抑制素基因（myostatin,MSTN）活性的降低或丧失所出现的”双肌“动物,给畜牧业生产带来了显著的经济效益,因此,许多畜牧学者探讨如何利用MSTN来提高动物的生产力。本文对肉用大型家畜牛、猪、绵羊、山羊MSTN基因国内外研究进展及应用前景进行了综述,为家畜MSTN基因的进一步研究提供一定的理论参考。     

猪肌生成抑制素在COS-7细胞中的表达及检测

本研究室构建的猪肌生成抑制素(MSTN)成熟蛋白编码序列的真核表达质粒pef-dhfr1a-MSTN,转染到COS-7细胞中,使猪MSTN成熟蛋白编码序列全长358个氨基酸在COS-7细胞中进行表达,利用Trizol试剂提取转染细胞的总RNA,借助RT-PCR和SDS-PAGE电泳方法,分别从mRNA水平和蛋白质水平上检测到了猪MSTN在COS-7细胞中的表达,并应用Western-blotting方法证实了猪MSTN表达的特异性。     

抑肌素基因mRNA在猪肌肉组织表达差异的研究

抑肌素基因(Myostatin，MSTN)是肌肉生长抑制素基因的简称，又称GDF-8(Growth and Differential Factor-8)基因，具有抑制骨骼肌生长的作用，是骨骼肌生长的负调控因子。该基因在动物分子水平定向育种、提高产肉性能上具有极大的应用前景。研究发现，在牛和绵羊的心肌、猪的乳腺及鱼类的多种组织中均发现有其表达。在调节脂肪积累、参与骨折愈合、调节排卵、心脏发育及心肌的组织修复、以及乳腺的发生和泌乳等过程中可能也具有重要作用。     

Myostatin基因研究进展

肌肉生长抑制素基因（Myostatin,MSTN）是1997年发现的骨骼肌生长发育负调控因子,属于TGF-β家族.研究证实人的Myostatin基因由3个外显子和2个内含子组成,在骨骼肌中特异性表达.目前,该基因已分别在人、牛和猪的染色体上定位.Myostatin是肌肉生长的负性调控因子,通过抑制成肌细胞的增殖而发挥作用.Myostatin突变或缺失均可异致肌肉质量的显著增加.文章主要阐述了肌肉生长抑制素基因的结构,功能,及其定位,并对其在畜牧业及医学上的应用前景作了综合论述.     

Growth factors controlling muscle development.

The enlarged muscles of certain breeds of cattle, such as the Belgian Blue, have been shown to result from a marked increase in the number of normal sized muscle fibers. Originally insulin-like growth factors (IGFs) were implicated in this myofiber hyperplasia, as IGFs have been shown to stimulate myoblast proliferation as well as maintain fiber differentiation. Recently it has been reported that mice lacking a myostatin gene, a member of the TGFbeta superfamily, have enhanced skeletal mass resulting from increased muscle fiber number and size. Mutations in this gene have been found in double-muscled cattle, indicating that myostatin is an inhibitor of muscle growth. Myostatin is expressed early in gestation and then maintained to adulthood in certain muscles. Myostatin expression in bovine muscle is highest during gestation when muscle fibers are forming and some of the myogenic regulatory factors have elevated expression over the same period as myostatin. Molecular expression of the IGF axis does not differ between Belgian Blue and normal muscled cattle, and IGF-II mRNA is increased throughout formation of secondary fibers in both breeds. However, myostatin and MyoD expression in muscle differ between normal and hypertrophied muscle cattle breeds. This evidence strongly suggests that lack of myostatin is associated with an increase in fiber number which then results in a marked increase in potential muscle mass in double-muscled cattle.     

Nucleotide sequence of myostatin gene and its developmental expression in skeletal muscles of Japanese Black cattle

Myostatin, a member of the transforming growth factor‐β superfamily, is a well known negative regulator of skeletal muscle growth. In the present study, the 6660 bp nucleotide sequence of the myostatin gene in Japanese Black cattle (JBC), including the entire coding region of 1128 bp, was determined. The amino acid sequence deduced from the nucleotide sequence of JBC was well conserved with its sequence of other cattle, although it was found that an Α→G transition at nucleotide position 641 results in the substitution of asparagine by serine at amino acid position 214. In order to examine the expression pattern of the myostatin gene in the skeletal muscles of JBC, its expression in three skeletal muscles, Semitendinosus (ST) muscle, Biceps femoris muscle and Longissimus lumborum muscle, of fetal and calf stages was analyzed by real time polymerase chain reaction. The highest level of the myostatin expression was observed in the fetal stage. In calf stages the highest expression was observed in ST muscle compared with the other two muscles. These results suggest that a higher expression of myostatin gene, especially in the fetal stage and in ST muscle during calf stages, is involved in the arrest in skeletal muscle growth and that its functional domains and genomic structure in JBC are well conserved with those in other mammals.     

Role of serum myostatin during the lactation period

Myostatin, also known as GDF-8 (Growth/Differentiation Factor-8), is a member of the TGF-beta superfamily that negatively regulates skeletal muscle mass in mammals. Mutation of the myostatin gene in mice, cattle, and humans causes a massively developed skeletal muscle, characterized by muscle hypertrophy and hyperplasia. Although myostatin is predominantly expressed in skeletal muscle tissue, several recent studies have shown the presence of myostatin protein in blood and suggested a possible role for circulating myostatin in the regulation of skeletal muscle mass. In the present study, we examined changes in the levels of active form myostatin (13 kDa) in serum after birth by Western blot analysis to predict the role of serum myostatin in early postnatal muscle growth in the rat. Interestingly, the amount of active form myostatin in serum increased after birth and then decreased along with ageing after weaning. To clarify the role of increased serum myostatin during the postnatal period, we administrated follistatin, an inhibitor of myostatin activity, into postnatal rats intraperitoneally just after birth. Follistatin-administration during the postnatal period caused selective hypertrophy of type II muscle fibers in the soleus muscle. These results demonstrate that myostatin in serum acts on skeletal muscle and negatively regulates early postnatal muscle growth.     

北京鸭肌肉生长抑制素基因多态与屠体性状关系分析

肌肉生长抑制素（Myostatin,MSTN）基因在发育和成熟的骨骼肌中特异表达,对肌肉具有负调控作用。应用聚合酶链式反应单链构象多态性（PCR-SSCP）的方法,对6周龄北京鸭2个群体（Z2系和Z4系）共200个个体Myostatin基因5’调控区进行SNP分析,并对所发现的单核苷酸多态性与胴体重、胸肌重、腿肌重、全净膛重、皮脂重、腹脂重、骨架重、胸肌率、腿肌率、皮脂率、腹脂率进行了关联分析。结果发现,A1/A2位点基因型（AA和AB型）对6周龄Z2系和Z4系北京鸭的腹脂重（P＜0.05）和胸肌重（P＜0.10）有显著影响,因此可以将Myostatin基因作为影响北京鸭Z2系和Z4系腹脂重和胸肌重的候选基因。     

利木赞牛抑肌素基因Q204X及nt821突变快速检测方法

抑肌素(GDF8)是骨骼肌细胞生长的重要负调控因子。抑肌素基因突变是牛"双肌"性状形成的分子遗传基础,在不同牛品种中存在着不同的抑肌素基因突变类型,在利木赞品种中,"双肌"性状主要是抑肌素基因第2外显子的Q204X型突变及第3外显子nt821突变。本研究报道一种新的检测该突变的简便方法。应用突变型与正常型引物在一次PCR反应中同时检测出不同的等位基因。对Q204X突变型PCR产物克隆测序分析表明,该片段确实含有一个能导致抑肌素功能缺陷的Q204X突变。     

动物肌肉生长发育调控的功能基因研究进展

成肌细胞的增殖和分化是受生肌决定因子 (MyoD)调控 ,生肌决定因子包括 4个基因 ,MyoDl(myf3)、Myogenin(MyoG)、Myf5、Myf 6 (herculin或MRF4 )。MyoD家族基因属于碱性螺旋 环 螺旋 (bHLH)转录因子 ,它能激活肌肉生成的特定基因。肌细胞生长抑制素 (MSTN ,Myostatin ,又称GDF 8) ,属于转化生长因子超家族 ,它通过负向控制肌细胞的生长发育 ,GDF 8基因缺失的小鼠表现出比正常小鼠具有“双肌现象”。     

牛双肌基因PCR-SSCP分析

双肌(肌肉生长抑制素)基因是一种肌肉生长的负调控因子,试验应用PCR-SSCP和测序的方法对我国秦川牛、南阳牛双肌基因的第3外显子进行了多态性分析.结果表明:第3外显子938位G→A的单核苷酸突变造成了南阳牛第3外显子扩增片段呈多态性;秦川牛中未发现突变.     

Myostatin expression and possible functions in animal muscle growth

Myostatin (also known as growth/differentiation factor-8) is a recently identified member of the transforming growth factor-β family of secreted regulatory factors. Mice having targeted disruption of the myostatin gene displayed a marked increase in muscle mass, up to three times normal size. Additionally, a myostatin mutation has been linked to double muscled cattle breeds characterized by a visible, generalized increase in muscle mass. Therefore, it is suggested that myostatin in muscle may be one of the long sought inhibitors that specifically control the growth of individual tissues or organs. In the present paper, we review involvement of myostatin in muscle growth of different species.     

牛肌肉生长抑制素基因的研究进展

肌肉生长抑制素,属TGF-β超家族,是一种骨骼肌生长发育的负调控因子。其生物活性的丧失或受到抑制,会导致骨骼肌增生从而引起动物肌肉的过度发育,表现为双肌性状。本文综述了MSTN基因的发现、结构特点、作用机制、在牛科物种中的研究进展及其应用前景。