Table 1 Non-coding RNAs in dosage compensation
Feature | roX RNA | Xist RNA |
|---|---|---|
Number of genes | 2 | 1 |
Site of production | X chromosome | X chromosome |
Length | 3.7 kb (roX1) 0.5–1.2 kb (roX2) | 19.3 Kb |
Expression duration | Retained over time | Transient |
Sex specific expression | Yes | Yes |
Role in compensasome-condensasome formation | Yes | Possible |
Necessity | Initiation, Maintenance | Initiation, Spreading |
Expansion in cis | Limited | Along the chromosome |
Expansion in trans | Yes | Yes |
Coating/Spreading | Limited (debatable) | Definite, large scale |