linkerDNAlængde

LinkerDNAlængde refers to the length of linker DNA, the stretch of DNA that connects adjacent nucleosomes in the chromatin fiber. Each nucleosome core particle wraps about 147 base pairs of DNA; the linker DNA between cores varies in length among organisms, cell types, and developmental stages.

The nucleosome repeat length (NRL) equals core DNA plus linker DNA, and in many eukaryotes it ranges roughly from 165 to 200 base pairs, corresponding to linker lengths of about 18 to 53 base pairs. In mammals, the average linker DNA length is commonly around 40 base pairs, contributing to an NRL near 187 base pairs.

Factors influencing linker length include occupancy of histone H1, chromatin remodeling activities, DNA sequence preferences, and cell type or developmental stage. Species-specific differences are common.

Longer linker DNA generally promotes a more extended 10 nm fiber and can affect transcription factor access, while shorter linkers favor tighter packing. Dynamic changes in linker length occur during transcription, replication, and DNA repair.

Measurement approaches include micrococcal nuclease digestion followed by sequencing (MNase-Seq) or gel analysis to determine nucleosome repeat length; direct imaging and chromatin conformation assays can also inform linker length estimates.