Kromatinen

Kromatinen is a term used in some contexts, particularly in older or specialized literature, to refer to chromatin. Chromatin is the complex of DNA and proteins that forms chromosomes within the nucleus of eukaryotic cells. The primary proteins involved are histones, which package the DNA into structural units called nucleosomes. This packaging allows the vast amount of DNA in a cell to fit within the nucleus and also plays a crucial role in gene regulation.

The structure of chromatin is dynamic and can change depending on the cell's needs. During cell division, chromatin condenses to form visible chromosomes. Outside of cell division, chromatin exists in a more relaxed state, allowing for transcription and replication of DNA. The organization of chromatin is hierarchical, with DNA wrapped around histones, which then further coil and fold into higher-order structures.

Variations in chromatin structure, such as the addition or removal of chemical tags on histones (epigenetic modifications), can alter gene expression without changing the underlying DNA sequence. This epigenetic regulation is vital for cellular differentiation and development. The term "kromatinen" is less common in modern molecular biology literature, with "chromatin" being the universally accepted term.