tef1

tef1 typically refers to the gene encoding translation elongation factor 1-alpha (EF-1α), a highly conserved GTPase that drives the delivery of aminoacyl-tRNA to the ribosome during eukaryotic protein synthesis. In the budding yeast Saccharomyces cerevisiae, TEF1 and TEF2 are paralogous genes that encode EF-1α; TEF1 is generally the main source of EF-1α expression and essential for growth.

EF-1α forms a cytosolic elongation factor-1 (EF-1) complex with accessory factors and cycles between GTP- and GDP-bound states. It binds aminoacyl-tRNA and, guided by GTP hydrolysis, delivers it to the ribosome A-site, enabling codon recognition and peptide bond formation. After GTP hydrolysis, EF-1α-GDP is recycled by exchange factors to rebind GTP.

TEF1‑α is highly conserved across eukaryotes. In yeast, TEF1 and TEF2 encode highly similar EF-1α proteins, with overlapping essential functions; loss of TEF1 is often lethal unless TEF2 compensates. In fungi, TEF1‑α sequences are widely used as molecular markers for species identification and phylogenetic analyses.

TEF1 promoters are among the strongest constitutive promoters used in yeast expression systems, driving robust transcription of heterologous genes in Saccharomyces cerevisiae and other yeasts. In molecular biology, TEF1‑α also serves as a housekeeping reference gene for normalization in RT-PCR studies.

Beyond its canonical role in translation, EF-1α export and non-canonical interactions have been reported in some organisms, including associations with cytoskeletal elements and stress responses. The TEF1 gene thus appears as a central, conserved component of the translation machinery with both basic and applied significance.