NUCLEOSOME Meaning and
Definition
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A nucleosome is a basic structural unit of DNA packaging in the nucleus of eukaryotic cells. It consists of a DNA molecule wrapped around a core of proteins called histones. The DNA double helix is wound around the histone proteins, forming a compact and organized structure.
The core of a nucleosome is composed of eight histone proteins, which are arranged in a protein complex called the histone octamer. The histone octamer consists of two sets of four different histone proteins: H2A, H2B, H3, and H4. The DNA strand wraps around this protein core in a left-handed superhelix shape for about 1.65 turns, forming a DNA-protein complex called a nucleosomal core particle.
The histone proteins play a crucial role in DNA packaging and organization. They have positively charged amino acids that interact with the negatively charged phosphate backbone of the DNA molecule, allowing the DNA to be tightly wound around the histone core. This wrapping prevents the long DNA molecules from becoming entangled and helps compact the DNA into a condensed structure known as chromatin.
Nucleosomes are the building blocks of chromatin, the material that makes up the chromosomes in the cell nucleus. They play a crucial role in gene regulation and DNA accessibility, as the compacted structure can limit or promote gene expression. Additionally, nucleosomes are dynamic structures that can be modified and manipulated by various enzymes, allowing for changes in gene activity and regulation.
Common Misspellings for NUCLEOSOME
- nucleosode
- bucleosome
- mucleosome
- jucleosome
- hucleosome
- nycleosome
- nhcleosome
- njcleosome
- nicleosome
- n8cleosome
- n7cleosome
- nuxleosome
- nuvleosome
- nufleosome
- nudleosome
- nuckeosome
- nucpeosome
- nucoeosome
- nuclwosome
- nuclsosome
- nucldosome
Etymology of NUCLEOSOME
The word "nucleosome" is derived from the combination of two Greek words: "nucleus" (meaning "kernel" or "core") and "soma" (meaning "body").
The term was coined in the mid-1970s by Roger Kornberg, an American biochemist and Nobel Laureate, to describe the basic structural unit of DNA packaging in eukaryotic cells. Nucleosomes are responsible for compacting the DNA molecule and play a vital role in gene regulation and chromosome organization.
