Chapter 5, Problem 16Q

Summary Introduction

To calculate: The packing ratio that has been achieved by wrapping DNA around the histone octamer.

Introduction: Histones that are present in the eukaryotic cell nucleus are alkaline proteins that enclose and organize the DNA into structural units called nucleosomes. In the center of the nucleosome core particle, an eight protein complex is occurs which is called the histone octamer. Histone proteins enclose the chromosomes into a condensed structure called as chromatin and this first level of DNA packaging appears like ‘beads on a string’ structure.

Summary Introduction

To calculate: How condensed is “beads on a string”DNA relative to a fully extended DNA if there is an additional 54bp of extended DNA  present in the linker between nucleosomes.

Introduction: Histones that are present in the eukaryotic cell nucleus are alkaline proteins that enclose and organize the DNA into structural units called nucleosomes. In the center of the nucleosome core particle, an eight protein complex is occurs which is called the histone octamer. Histone proteins enclose the chromosomes into a condensed structure called as chromatin and this first level of DNA packaging appears like ‘beads on a string’ structure.

Summary Introduction

To calculate: What fraction of the 10,000-fold condensation that occurs at mitosis does this first level of DNA packing represent.

Introduction: Histones that are present in the eukaryotic cell nucleus are alkaline proteins that enclose and organize the DNA into structural units called nucleosomes. In the center of the nucleosome core particle, an eight protein complex is occurs which is called the histone octamer. Histone proteins enclose the chromosomes into a condensed structure called as chromatin and this first level of DNA packaging appears like ‘beads on a string’ structure.