TABLE 1.
Translation initiation factors in yeast
| Initiation factor with subunits (reference) | Proposed functiona | S. cerevisiae gene name(s) | Proposed new gene designation(s)b |
|---|---|---|---|
| eIF1d (106, 607) | Met-tRNAi and mRNA binding to 40S | SUI1 | tif1 |
| eif1ad (580) | 40s-60s dissociation; met-trnai binding | tif11 | tif1 |
| eif2c, α, β, γ (94, 135, 200) | aug selection | sui2, sui3, gcd11 | tif211, tif212, tif213 |
| eif2b, α, β, γ, δ, ɛ (226) | guanine nucleotide exchange on eif2 | gcn3, gcd7, gcd1, gcd2, gcd6 | tif221, tif222, tif223, tif224, tif225 |
| eif3, α, β, χ, δ, ɛ, ξ, η, θ (169, 199, 399) | met-trnai and mrna binding to 40s; 40s-60s dissociation | prti, gcd10 | tif31, tif32, tif33, tif34, tif35 |
| eif4a (333) | rna-binding helicase, atpase | tif1, tif2 | tif41a, tif41b |
| eif4b (13, 98) | rna binding promotes helicase | tif3 (stmi) | tif42 |
| eif4e (8, 63) | cap binding | cdc33 | tif45 |
| eif4g1 (p150), eif4g2 (p130) (180) | interactions with eif3, eif4e, and pab1p | tif4631 and tif4632, respectively | tif47a and tif47b, respectively |
| eif4h (458) | stimulation of activities of eif4f components and eif4b | tif48 | |
| eif5 (85) | ejection of eifs | tif5 | tif5 |
| eif5a (490, 620) | function unclear; mutation affects mrna stability | tif51a, tif51b | tif51a, tif51b |
| eif6 (369) | 40s:60s dissociation | tif6 |
a
these are functions proposed primarily on the basis of in vitro investigations of (partially) purified components.
b
these are the designations proposed for the s. pombe initiation factors (334).
c
note the recently discovered existence of yif2 (89b).
d
mammalian eif1 and eif1a have now been implicated in start codon selection (435a).