Table 1.
Characteristics of the major protein components of the miRNA-guided RNA silencing pathway.
| Protein | Role/function | Accession number (mRNA) | mRNA (bp) | Accession number (protein) | Amino acids | Molecular weight (kDa)* | Isoelectric point* | Intracellular localization |
| Drosha | Processing of pri-miRNA into pre-miRNA | NM_013235 | 4764 | NP_037367 | 1374 | 159 | 7.81 | Nuclear |
| DGCR8 | Assistance of Drosha function in the microprocessor | NM_022720 | 4461 | NP_073557 | 773 | 86 | 5.94 | Nuclear |
| Exportin-5 | Nuclear export of pre-miRNA | NM_020750 | 5231 | NP_065801 | 1204 | 136 | 5.79 | Nuclear membrane |
| Dicer | Processing of pre-miRNA into miRNA:miRNA* | NM_177438 | 10 276 | NP_803187 | 1922 | 219 | 5.68 | Cytoplasmic, ER |
| TRBP | Assistance of Dicer function in pre-miRNA processing complex | M60801 | 1368 | AAA36765 | 345 | 38 | 7.38 | Cytoplasmic |
| Ago2 | Component of miRNPs, repression of translation | NM_012154 | 3567 | NP_036286 | 859 | 97 | 9.19 | Cytoplasmic |
| FMRP | Component of miRNPs, repression of translation | NM_002024 | 4362 | NP_002015 | 632 | 71 | 7.42 | Cytoplasmic nuclear |
*Calculated from protein calculator v.3.2 (http://www.scripps.edu/~cdputnam/protcalc.html). ER, endoplasmic reticulum.