HGNC Approved Gene Symbol: TEF
Cytogenetic location: 22q13.2 Genomic coordinates (GRCh38) : 22:41,367,455-41,399,326 (from NCBI)
TEF is a member of the PAR (proline and acidic amino acid-rich) subfamily of basic region/leucine zipper (bZIP) transcription factors (Drolet et al., 1991).
Drolet et al. (1991) reported the identification and characterization of thyrotroph embryonic factor (TEF), a transcription factor expressed in the developing anterior pituitary gland. TEF was shown to be a member of the PAR (proline and acidic amino acid-rich) subfamily of basic region/leucine zipper (bZIP) transcription factors. The pattern of TEF gene expression in embryonic rat anterior pituitary gland corresponded temporally and spatially to the onset of TSHB (188540) gene expression. In contrast to this restricted pattern of expression during embryogenesis, TEF transcripts appeared in several tissues in the mature organism. TEF shows homology to another member of the PAR bZIP family, the albumin D box-binding protein (DBP; 124097). TEF and DBP transcripts were found to be coexpressed in a pituitary cell line.
Khatib et al. (1994) found that DBP and TEF mRNAs were expressed in all tissues and cell lines examined, including brain, lung, liver, spleen, and kidney.
Gachon et al. (2004) stated that the expression of 3 PAR bZIP transcription factors, TEF, DBP, and HLF (142385), show high-amplitude circadian expression in the suprachiasmatic nucleus, the master circadian pacemaker in mammals. However, they are expressed at nearly invariable levels in most brain regions, in which clock gene expression cycles only with low amplitude. RT-PCR of mouse tissues demonstrated that all 3 transcription factors show higher amplitude circadian cycles of expression in liver than in brain. Genes regulated by the PAR bZIP transcription factors showed similar circadian cycles of expression, with higher amplitude in mouse liver. Transcriptome profiling revealed that pyridoxal kinase (PDXK; 179020), a coenzyme of many enzymes involved in amino acid and neurotransmitter metabolism, is a target gene for PAR bZIP proteins in liver and brain.
Drolet et al. (1991) found that TEF can bind to and transactivate the TSHB promoter, and that TEF and DBP proteins could form heterodimers.
By fluorescence in situ hybridization, Khatib et al. (1994) demonstrated that the human TEF gene is located on 22q13. The assignment was confirmed by study of human chromosome segregation in somatic cell hybrids.
Using an interspecific backcross, Lossie et al. (1993) found that the mouse Tef gene is located on mouse chromosome 15.
Gachon et al. (2004) found that mice homozygous for Hlf and Tef mutant alleles were morphologically normal and fertile. Animals devoid of any 2 or 3 PAR bZIP transcription factors were anatomically normal and fertile, but those lacking all 3 had dramatically shortened life span. Within the first month after birth, homozygous triple-knockout mice developed spontaneous epilepsy characterized by myoclonic, tonic-clonic, and possibly absence seizures, in addition to audiogenic seizure susceptibility. PAR bZIP-deficient mice show decreased brain levels of pyridoxal-5-phosphate, serotonin, and dopamine. Gachon et al. (2004) concluded that the expression of some clock-controlled genes may have to remain within narrow limits in the brain and undergo only low-amplitude cycles of expression in most brain regions.
Drolet, D. W., Scully, K. M., Simmons, D. M., Wegner, M., Chu, K., Swanson, L. W., Rosenfeld, M. G. TEF, a transcription factor expressed specifically in the anterior pituitary during embryogenesis, defines a new class of leucine zipper proteins. Genes Dev. 5: 1739-1753, 1991. [PubMed: 1916262] [Full Text: https://doi.org/10.1101/gad.5.10.1739]
Gachon, F., Fonjallaz, P., Damiola, F., Gos, P., Kodama, T., Zakany, J., Duboule, D., Petit, B., Tafti, M., Schibler, U. The loss of circadian PAR bZip transcription factors results in epilepsy. Genes Dev. 18: 1397-1412, 2004. [PubMed: 15175240] [Full Text: https://doi.org/10.1101/gad.301404]
Khatib, Z. A., Inaba, T., Valentine, M., Look, A. T. Chromosomal localization and cDNA cloning of the human DBP and TEF genes. Genomics 23: 344-351, 1994. [PubMed: 7835883] [Full Text: https://doi.org/10.1006/geno.1994.1510]
Lossie, A. C., Gordon, D. F., Camper, S. A. Localization of thyrotropin-releasing hormone receptor and thyrotroph embryonic factor on mouse chromosome 15. Mammalian Genome 4: 621-623, 1993. [PubMed: 7903570] [Full Text: https://doi.org/10.1007/BF00361398]