Table I. Summary of newly identified miRNAs.
| novel miRNAs | |||
|---|---|---|---|
| C. elegans | Drosophila | Homo sapiens | |
| Lagos-Quintana et al., 2001 | 1 | 14 | 19 |
| Lau et al., 2001 | 52 | 6 | 4 |
| Lee and Ambros, 2001 | 15 | 3 | 2 |
| Total1 | 57 | 20 | 24 |
| Overlap2 | 11 | 4 | 2 |
| Northern analysis (positive)3 | 34 (29) | 15 (14) | 19 (17) |
| 5' arm derived4 (%) | 28 | 36 | 58 |
99 unique sequences from the three organisms account for 91 novel miRNAs after correction for putative orthologues. Not included are lin-4 and let-7, which were also identified.
1
Number of unique sequences.
2
Sequences identified by more than one group.
3
Expression of the indicated number of miRNAs was investigated by Northern analysis. Numbers in brackets give the numbers of miRNAs for which a transcript of ∼22 nt was detected in this analysis. 3 additional transcripts were verified as precursors only.
4
Mature RNA derived from 5' arm of precursor.