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Explore DNA conformation, supercoiling, histone packaging, telomere replication, and more. Learn about eukaryotic chromosome formation and molecular processes.
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DNA can assume alternative conformations such as partially melted or supercoiled states
Mechanism of folding of a bacterial chromosome There are many supercoiled loops (~100 in E. coli) attached to a central core. Each loop can be independently relaxed or condensed.
Packing of DNA in an eukaryotic cell involves wrapping around a core of basic (positively charged) proteins called histones
Steps in the folding of DNA to create an eukaryotic chromosome
The rate of renaturation of single stranded DNA depends upon the concentration and sequence complexity
The rates of renaturation of DNAs with different kinetic complexities
DNA of an eukaryotic cell has several components with different kinetic complexities
DNA with low kinetic complexity is located in the middle (near the centromere) and at the ends (near the telomeres) of a chromosome
Structure of the centromere in a Saccharomyces chromosome The centromere DNA has 4 centromere determining elements (CDEs)
Mechanism of replication of telomere DNA by the enzyme telomerase The enzyme telomerase has a RNA molecule that serves as the template for telomere DNA synthesis.
Proposed 4-stranded structure of telomere DNA in two protozoans