Table 2.
Sizes of functional chromatin units measured with different methods.
| Reference | Year | Method | Nomenclature/Structure | Organism (cell line) | Median/mean size | Size range | |
|---|---|---|---|---|---|---|---|
| Function | Huberman and Riggs | 1968 | Labeled DNA autoradiography | Replication sections (IOD) | Hamster and Human | 7 – 30 µm (15–60 µm) |
(up to 160 µm) |
| Lau and Arrighi | 1981 | Premature chromosome condensation | Replication units | Hamster (CHO) | 0.6 µm | 0.2–1.2 µm | |
| Nakamura, Morita and Sato | 1986 | Conventional microscopy foci analysis | Replication domains | Rat (3Y1-B) | 1000 kb | - | |
| Nakayasu and Berezney | 1989 | Conventional microscopy foci analysis | Replication granules | Kangaroo (PtK1) | 0.5 µm | 0.4–0.6 µm (late S up to few µm) | |
| Jackson and Pombo | 1998 | Replication labeling on DNA fibers | IOD (eq. to a replicon) | Human (HeLa) | 144 kb | 25 – 325 kb | |
| Conventional microscopy foci analysis | Replicon clusters | Human (HeLa) | 0.8 Mb | - | |||
| Chagin et al. | 2016 | Replication labeling on DNA fibers | IOD (eq. to a replicon) | Human (HeLa Kyoto) | 189 kb | ± 121 kb | |
| IOD (eq. to a replicon) | Mouse (C2C12) | 162 kb | ± 100 kb | ||||
| Natale, Rapp et al. | 2017 | 3D-SIM of gH2AX-labeled chromatin | Repair nano-foci | Human (HeLa) | 75 kb | 34 kb – 159 kb |