EIF2S2
Encyclopedia
Eukaryotic translation initiation factor 2 subunit 2 is a protein
that in humans is encoded by the EIF2S2 gene
.
2 (EIF-2
) functions in the early steps of protein synthesis by forming a ternary complex with GTP
and initiator tRNA
and binding to a 40S
ribosomal
subunit. EIF-2 is composed of three subunits, alpha
, beta (this article), and gamma
, with the protein encoded by this gene representing the beta subunit. The beta subunit catalyzes the exchange of GDP
for GTP
, which recycles the EIF-2 complex for another round of initiation.
transcription factor
.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the EIF2S2 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Function
Eukaryotic translation initiation factorEukaryotic initiation factor
Eukaryotic initiation factors are proteins involved in the initiation phase of eukaryotic translation. They function in forming a complex with the 40S ribosomal subunit and Met-tRNAi called the 43S preinitation complex , recognizing the 5' cap structure of mRNA and recruiting the 43S PIC to mRNA,...
2 (EIF-2
EIF2
Eukaryotic Initiation Factor 2 is a eukaryotic initiation factor. It is required in the initiation of translation. In this fundamental process of life, the ribosome builds proteins according to the information encoded on the mRNA. eIF2 mediates the binding of tRNAmet to the ribosome in a...
) functions in the early steps of protein synthesis by forming a ternary complex with GTP
Guanosine triphosphate
Guanosine-5'-triphosphate is a purine nucleoside triphosphate. It can act as a substrate for the synthesis of RNA during the transcription process...
and initiator tRNA
Transfer RNA
Transfer RNA is an adaptor molecule composed of RNA, typically 73 to 93 nucleotides in length, that is used in biology to bridge the three-letter genetic code in messenger RNA with the twenty-letter code of amino acids in proteins. The role of tRNA as an adaptor is best understood by...
and binding to a 40S
40S
40S is the small subunit of eukaryotic ribosomes.It interacts with the internal ribosome entry site of the hepatitis C virus.The following is a list of proteins contained in the 40S ribosome:...
ribosomal
Ribosome
A ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule....
subunit. EIF-2 is composed of three subunits, alpha
EIF2S1
Eukaryotic translation initiation factor 2 subunit 1 is a protein that in humans is encoded by the EIF2S1 gene.-Function:The protein encoded by this gene is the alpha subunit of the translation initiation factor eIF2 complex which catalyzes the first regulated step of protein synthesis initiation,...
, beta (this article), and gamma
EIF2S3
Eukaryotic translation initiation factor 2 subunit 3 is a protein that in humans is encoded by the EIF2S3 gene.-Function:Eukaryotic translation initiation factor 2 functions in the early steps of protein synthesis by forming a ternary complex with GTP and initiator tRNA and binding to a 40S...
, with the protein encoded by this gene representing the beta subunit. The beta subunit catalyzes the exchange of GDP
Guanosine diphosphate
Guanosine diphosphate, abbreviated GDP, is a nucleoside diphosphate. It is an ester of pyrophosphoric acid with the nucleoside guanosine. GDP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase guanine....
for GTP
Guanosine triphosphate
Guanosine-5'-triphosphate is a purine nucleoside triphosphate. It can act as a substrate for the synthesis of RNA during the transcription process...
, which recycles the EIF-2 complex for another round of initiation.
Regulation
Both eIF2-alpha and eIF2-beta expression is regulated by the NRF1NRF1
Nuclear respiratory factor 1, also known as Nrf1, Nrf-1, NRF1 and NRF-1, encodes a protein that homodimerizes and functions as a transcription factor which activates the expression of some key metabolic genes regulating cellular growth and nuclear genes required for respiration, heme biosynthesis,...
transcription factor
Transcription factor
In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow of genetic information from DNA to mRNA...
.