Protein Synthesis And Chromosomes
DNA is bound up within chromatids, which serve as storage unit for the DNA. In order for an mRNA molecule to be transcribed from a DNA template, the DNA needs to be freed from its tightly bound and condensed conformation so that the RNA molecule can form on its exposed strands during transcription. Some evidence exists that transcription can take place through histones. However, most often the genes on the DNA that have been activated after DNA binding protein unwind the chromatid structure. This loosened, transcriptionally active regions of DNA is microscopically resembles puffs on the chromosomes. When RNA transcription concludes, the puffs receed and the chromosome is thought to resume its original conformation.
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