[Structure of interphase chromosomes].
The chromosomes are based on a structural unit, the nucleosome. It consists of a protein care and about 200 base pairs of DNA arranged on its outside in a regular way, probably as a spiral. The protein care is a histone octamer containing two copies each of the four main types of histones, H2A, H2B, H3, and H4. The shape of the nucleosome ressembles a short wedge shaped cylinder of 110 A x 110 A x 60 A. The nucleosomes are closely spaced and linked by the continuous DNA. Since the fifth histone, H1, stabilizes the interaction of adjacent nucleosomes, it is considered to be involved in the formation of higher structural orders in the chromosomes.
D002875:Chromosomes / Q000648:ultrastructure*; D004247:DNA; D006657:Histones; D006801:Humans; D007399:Interphase; D008970:Molecular Weight
D006657:Histones; D004247:DNA
Struktur der Interphasenchromosomen.