Myogenin, is a transcriptional activator encoded by the MYOG gene. [5] Myogenin is a muscle-specific basic-helix-loop-helix (bHLH) transcription factor involved in the coordination of skeletal muscle development or myogenesis and repair. Myogenin is a member of the MyoD family of transcription factors, which also includes MyoD, Myf5, and MRF4.
In mice, myogenin is essential for the development of functional skeletal muscle. Myogenin is required for the proper differentiation of most myogenic precursor cells during the process of myogenesis. When the DNA coding for myogenin was knocked out of the mouse genome, severe skeletal muscle defects were observed. Mice lacking both copies of myogenin (homozygous-null) suffer from perinatal lethality due to the lack of mature secondary skeletal muscle fibers throughout the body. [6] [7]
In cell culture, myogenin can induce myogenesis in a variety of non-muscle cell types.
Myogenin has been shown to interact with:
MyoD, also known as myoblast determination protein 1, is a protein in animals that plays a major role in regulating muscle differentiation. MyoD, which was discovered in the laboratory of Harold M. Weintraub, belongs to a family of proteins known as myogenic regulatory factors (MRFs). These bHLH transcription factors act sequentially in myogenic differentiation. Vertebrate MRF family members include MyoD1, Myf5, myogenin, and MRF4 (Myf6). In non-vertebrate animals, a single MyoD protein is typically found.
A basic helix–loop–helix (bHLH) is a protein structural motif that characterizes one of the largest families of dimerizing transcription factors. The word "basic" does not refer to complexity but to the chemistry of the motif because transcription factors in general contain basic amino acid residues in order to facilitate DNA binding.
Myogenesis is the formation of skeletal muscular tissue, particularly during embryonic development.
The scleraxis protein is a member of the basic helix-loop-helix (bHLH) superfamily of transcription factors. Currently two genes have been identified to code for identical scleraxis proteins.
Myogenic regulatory factors (MRF) are basic helix-loop-helix (bHLH) transcription factors that regulate myogenesis: MyoD, Myf5, myogenin, and MRF4.
An E-box is a DNA response element found in some eukaryotes that acts as a protein-binding site and has been found to regulate gene expression in neurons, muscles, and other tissues. Its specific DNA sequence, CANNTG, with a palindromic canonical sequence of CACGTG, is recognized and bound by transcription factors to initiate gene transcription. Once the transcription factors bind to the promoters through the E-box, other enzymes can bind to the promoter and facilitate transcription from DNA to mRNA.
In the field of molecular biology, myocyte enhancer factor-2 (Mef2) proteins are a family of transcription factors which through control of gene expression are important regulators of cellular differentiation and consequently play a critical role in embryonic development. In adult organisms, Mef2 proteins mediate the stress response in some tissues. Mef2 proteins contain both MADS-box and Mef2 DNA-binding domains.
The gene extramachrochaetae (emc) is a Drosophila melanogaster gene that codes for the Emc protein, which has a wide variety of developmental roles. It was named, as is common for Drosophila genes, after the phenotypic change caused by a mutation in the gene (macrochaetae are the longer bristles on Drosophila).
Transcription factor 3, also known as TCF3, is a protein that in humans is encoded by the TCF3 gene. TCF3 has been shown to directly enhance Hes1 expression.
DNA-binding protein inhibitor ID-2 is a protein that in humans is encoded by the ID2 gene.
Myocyte-specific enhancer factor 2C also known as MADS box transcription enhancer factor 2, polypeptide C is a protein that in humans is encoded by the MEF2C gene. MEF2C is a transcription factor in the Mef2 family.
Serum response factor, also known as SRF, is a transcription factor protein.
DNA-binding protein inhibitor ID-1 is a protein that in humans is encoded by the ID1 gene.
Myocyte-specific enhancer factor 2A is a protein that in humans is encoded by the MEF2A gene. MEF2A is a transcription factor in the Mef2 family. In humans it is located on chromosome 15q26. Certain mutations in MEF2A cause an autosomal dominant form of coronary artery disease and myocardial infarction.
Transcription factor 12 is a protein that in humans is encoded by the TCF12 gene.
"Basic helix-loop-helix family, member e41", or BHLHE41, is a gene that encodes a basic helix-loop-helix transcription factor repressor protein in various tissues of both humans and mice. It is also known as DEC2, hDEC2, and SHARP1, and was previously known as "basic helix-loop-helix domain containing, class B, 3", or BHLHB3. BHLHE41 is known for its role in the circadian molecular mechanisms that influence sleep quantity as well as its role in immune function and the maturation of T helper type 2 cell lineages associated with humoral immunity.
In molecular biology, the myogenic determination factor 5 proteins are a family of proteins found in eukaryotes. This family includes the Myf5 protein, which is responsible for directing cells to the skeletal myocyte lineage during development. Myf5 is likely to act in a similar way to the other MRF4 proteins such as MyoD which perform the same function. These are histone acetyltransferases and histone deacetylases which activate and repress genes involved in the myocyte lineage.
Myogenic factor 5 is a protein that in humans is encoded by the MYF5 gene. It is a protein with a key role in regulating muscle differentiation or myogenesis, specifically the development of skeletal muscle. Myf5 belongs to a family of proteins known as myogenic regulatory factors (MRFs). These basic helix loop helix transcription factors act sequentially in myogenic differentiation. MRF family members include Myf5, MyoD (Myf3), myogenin, and MRF4 (Myf6). This transcription factor is the earliest of all MRFs to be expressed in the embryo, where it is only markedly expressed for a few days. It functions during that time to commit myogenic precursor cells to become skeletal muscle. In fact, its expression in proliferating myoblasts has led to its classification as a determination factor. Furthermore, Myf5 is a master regulator of muscle development, possessing the ability to induce a muscle phenotype upon its forced expression in fibroblastic cells.
Myogenic factor 6 is a protein that in humans is encoded by the MYF6 gene. This gene is also known in the biomedical literature as MRF4 and herculin. MYF6 is a myogenic regulatory factor (MRF) involved in the process known as myogenesis.
Harold M. "Hal" Weintraub was an American scientist who lived from 1945 until his death in 1995 from an aggressive brain tumor. Only 49 years old, Weintraub left behind a legacy of research.