[Campbell Biology P.432] The MyoD gene is described as a "master regulatory gene" for muscle... | Practice Question
The MyoD gene is described as a "master regulatory gene" for muscle cell differentiation. Based on the provided text, which statement accurately reflects its function and/or limitations?
A: MyoD directly causes all types of fully differentiated nonmuscle cells to transform into muscle cells, regardless of their original state.
B: MyoD functions as a ribosomal RNA that facilitates protein synthesis necessary for muscle development.
C: MyoD is a transcription factor that binds to enhancers of target genes, stimulating their expression, and its effect is perpetuated by positive feedback, though its activity may require specific co-regulatory proteins in target cells.
D: The activation of muscle-specific genes is solely dependent on MyoD, making it the only protein required for muscle cell differentiation.
Explanation
The text explains that MyoD protein is a transcription factor that binds to enhancers of target genes, stimulating their expression. It also mentions that MyoD stimulates the expression of the myoD gene itself positive feedback and that its activity requires a 'particular combination of regulatory proteins' to work on all kinds of cells, indicating its limitations.