Table 3.
Old introns
| Protein | Intron position | Status |
|---|---|---|
| TPI | 38 | In |
| TPI | 79 | Out |
| TPI | 108 | Out |
| TPI | 152 | In |
| TPI | 181/4 | In |
| TPI | 210 | In |
| GST | 148/51 | In |
| HEMO | 30 | Out |
| HEMO | 100 | In |
| ALDOL | 266/9 | In |
| PFK | 264/6 | In |
| GAPDH | 9 | In |
| GAPDH | 43 | In |
| GAPDH | 75/8/9 | In |
| GAPDH | 146/7 | Out |
| PGK | 22 | In |
| PGK | 91/2/3 | In |
| CUSOD | 23/4 | Out |
| HSP70 | 69 | In |
| ENOL | 60/4 | Out |
A listing of 20 “ancient” introns identified as having matching positions in three out of four groups of vertebrates, invertebrates, plants, or fungi. Introns were considered homologous if they had slid up to four codons. The status column defines their character with respect to the linker regions for 28-Å modules (using the average position for slid introns). Fourteen of the 20 intron positions are within the linker regions rather than the 6.4 expected: χ2 = 13.3, P < 0.0003.