Linkers in Mammalian Chromosomal DNA
Ever since the helical model for DNA was proposed by Watson and Crick, the possibility that it does not provide a complete description of the architecture of eukaryotic chromosomal DNA has been the subject of sporadic, but increasing, experimentation and hypothesis. The arguments have generally centered on the proposition that eukaryotic DNA is discontinuous in the Watson-Crick sense, and it is in that sense that I will consider DNA continuity for the remainder of this article. The rationale behind the questioning has been based upon criteria ranging from experimental evidence to such innate feelings as: “All that DNA just cannot be packed into the nucleus or the chromosome without folding points!” Conversely, proponents of the concept that eukaryotic chromosomal DNA is continuous have based their arguments on experimental data or on the feeling: “The DNA in the eukaryotic chromosome must be continuous, therefore experimental evidence to the contrary must be artifactual!” Unfortunately, in certain areas, the latter feeling has been elevated to the rank of religious dogma.
KeywordsRotor Speed Sedimentation Coefficient Sedimentation Profile Residual Protein Eukaryotic Chromosome
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