Eukaryotic translation initiation factor 5A-1 is a protein that in humans is encoded by the EIF5A gene. [5]
It is the only known protein to contain the unusual amino acid hypusine [Nε-(4-amino-2-hydroxybutyl)-lysine], which is synthesized on eIF5A at a specific lysine residue from the polyamine spermidine by two catalytic steps. [6]
EF-P is the bacterial homolog of eIF5A, which is modified post-translationally in a similar but distinct way. [7] [8] Both proteins are believed to catalyze peptide bond formation and help resolve ribosomal stalls, making them elongation factors despite the "initiation factor" name originally assigned. [9]
Germline deleterious heterozygous EIF5A variants cause Faundes-Banka syndrome. [10] [11] This rare human disorder is characterized by variable combinations of developmental delay, microcephaly, micrognathia and dysmorphic features.
The TATA-binding protein (TBP) is a general transcription factor that binds specifically to a DNA sequence called the TATA box. This DNA sequence is found about 30 base pairs upstream of the transcription start site in some eukaryotic gene promoters.
EF-Tu is a prokaryotic elongation factor responsible for catalyzing the binding of an aminoacyl-tRNA (aa-tRNA) to the ribosome. It is a G-protein, and facilitates the selection and binding of an aa-tRNA to the A-site of the ribosome. As a reflection of its crucial role in translation, EF-Tu is one of the most abundant and highly conserved proteins in prokaryotes. It is found in eukaryotic mitochondria as TUFM.
Hypusine is an uncommon amino acid found in all eukaryotes and in some archaea, but not in bacteria. The only known proteins containing the hypusine residue is eukaryotic translation initiation factor 5A (eIF-5A) and a similar protein found in archaea. In humans, two isoforms of eIF-5A have been described: eIF5A-1 and eIF5A-2. They are encoded by two distinct genes EIF5A and EIF5A2. The protein is involved in protein biosynthesis and promotes the formation of the first peptide bond. The region surrounding the hypusine residue is highly conserved and is essential to the function of eIF5A. Thus, hypusine and eIF-5A appear to be vital for the viability and proliferation of eukaryotic cells.
60S ribosomal protein L5 is a protein that in humans is encoded by the RPL5 gene.
Eukaryotic translation initiation factor 4 gamma 1 is a protein that in humans is encoded by the EIF4G1 gene.
Eukaryotic translation initiation factor 2 subunit 1 (eIF2α) is a protein that in humans is encoded by the EIF2S1 gene.
Eukaryotic translation initiation factor 4 gamma 3 is a protein that in humans is encoded by the EIF4G3 gene. The gene encodes a protein that functions in translation by aiding the assembly of the ribosome onto the messenger RNA template. Confusingly, this protein is usually referred to as eIF4GII, as although EIF4G3 is the third gene that is similar to eukaryotic translation initiation factor 4 gamma, the second isoform EIF4G2 is not an active translation initiation factor.
Deoxyhypusine synthase is an enzyme that in humans is encoded by the DHPS gene.
Eukaryotic translation initiation factor 2 subunit 3 (eIF2γ) is a protein that in humans is encoded by the EIF2S3 gene.
Eukaryotic translation initiation factor 4B is a protein that in humans is encoded by the EIF4B gene.
Eukaryotic translation initiation factor 3 subunit H (eIF3h) is a protein that in humans is encoded by the EIF3H gene.
Valyl-tRNA synthetase is an enzyme that in humans is encoded by the VARS gene.
Eukaryotic translation initiation factor 3 subunit L (eIF3l), less commonly known as EIF3EIP, is a protein that in humans is encoded by the EIF3L gene.
Eukaryotic translation initiation factor 4E type 2 is a protein that in humans is encoded by the EIF4E2 gene. It belongs to the eukaryotic translation initiation factor 4E family.
Eukaryotic translation initiation factor 5A pseudogene 1, also known as EIF5AP1, is a human gene.
Ligatin, otherwise known as eIF2D, is a protein that in humans is encoded by the LGTN gene. This protein is not a component of the heterotrimeric eIF2 complex, but instead functions in different pathways of eukaryotic translation.
Eukaryotic translation initiation factor 5A-2 is a protein that in humans is encoded by the EIF5A2 gene.
Eukaryotic initiation factor 4A-II is a protein that in humans is encoded by the EIF4A2 gene.
Deoxyhypusine synthase (EC 2.5.1.46, spermidine:eIF5A-lysine 4-aminobutyltransferase (propane-1,3-diamine-forming)) is an enzyme with systematic name (eIF5A-precursor)-lysine:spermidine 4-aminobutyltransferase (propane-1,3-diamine-forming). This enzyme catalyses the following chemical reaction
Archaeal initiation factors are proteins that are used during the translation step of protein synthesis in archaea. The principal functions these proteins perform include ribosome RNA/mRNA recognition, delivery of the initiator Met-tRNAiMet, methionine bound tRNAi, to the 40s ribosome, and proofreading of the initiation complex.