Generic Structure of a Eukaryotic m RNA 3untranslated

Generic Structure of a Eukaryotic m. RNA 3’-untranslated region (3’-UTR) 5’-untranslated region (5’-UTR) Open Reading Frame (ORF) AUG 7 -Me-Gppp. G cap UAA stem-loop structures stem-loop cleavage structures & poly(A) addition site Initiation codon context -6 -5 -4 -3 -2 -1 +4 Kozak (mammalian) consensus: G C C A C C G -6 -5 -4 -3 -2 -1 (AUUUA)n +4 S. cerevisiae (yeast) consensus: (GC-poor) A x A (U) (AAA)n poly(A) tail

7 -methyl-guanine R 1 and R 2 = H or CH 3 m. RN A-3’-O H

• ATP and GTP • GTP

Gcn 2 & other e. IF 2 kinases

Mammalian e. IF 4 G 1

e. IF 4 E

e. IF 4 G e. IF 3 Composed of 13 distinct gene products (e. IF 3 a-e. IF 3 m) m. RNA 40 S subunit

e. IF 3

Translation Factor Yeast Gene Name Size (residues) Function / Comments e. IF 4 E CDC 33 213 7 Me. G cap-binding protein e. IF 4 E-BP 1 CAF 20 161 Cdc 33 -binding protein e. IF 4 E-BP 2 EAP 1 632 Cdc 33 -binding protein e. IF 4 G 1 TIF 4631 952 Scaffold protein, isoform 1 e. IF 4 G 2 TIF 4632 914 Scaffold protein, isoform 2 e. IF 4 A 1 TIF 1 395 RNA-dependent RNA helicase, isoform 1 e. IF 4 A 2 TIF 2 395 RNA-dependent RNA helicase, isoform 2 e. IF 4 B TIF 3 436 RNA-binding protein, stimulates e. IF 4 A PAB 1 577 Poly(A)-binding protein e. IF 3 a TIF 32 / RPG 1 964 p 110 subunit of e. IF 3 b PRT 1 763 p 90 subunit of e. IF 3, RNA-binding protein e. IF 3 c NIP 1 812 p 93 subunit of e. IF 3, required for nucleocytoplasmic transport of e. IF 3 g TIF 35 274 p 33 subunit of e. IF 3, RNA-binding protein e. IF 3 i TIF 34 347 p 39 subunit of e. IF 3, two WD 40 repeats e. IF 3 j HCR 1 265 p 29 subunit of e. IF 3, binds to A site and m. RNA entry channel of 40 S e. IF 3 ? SUI 1 108 p 16 subunit of e. IF 3, involved in initiation codon recognition e. IF 3 ? TIF 31 / CLU 1 964 p 135 subunit of e. IF 3, role in scanning for AUG e. IF 3 ? GCD 10 478 p 62 subunit of e. IF 3, RNA-binding protein e. IF 3 ? GCD 14 383 t. RNA 1 -methyladenosine methyltransferase, when associated with Gcd 10