Alternative titles; symbols
HGNC Approved Gene Symbol: TRAK2
Cytogenetic location: 2q33.1 Genomic coordinates (GRCh38) : 2:201,377,207-201,451,458 (from NCBI)
By sequencing candidate genes in the ALS2 (205100) critical region, followed by RT-PCR and 5-prime RACE of brain and lymphocyte total RNA, Hadano et al. (2001) cloned ALS2CR3. The deduced 914-amino acid protein has a calculated molecular mass of about 101.4 kD. ALS2CR3 contains a coiled-coil domain that shares significant homology with the coiled-coil region in huntingtin-associated protein-1 (HAP1; 600947). Northern blot analysis revealed ubiquitous expression of 7.0- and 4.5-kb transcripts, reflecting the use of 2 alternate polyadenylation signals; expression was highest in heart.
Using a sequence from the beta-2 subunit of the GABA-A receptor (GABRB2; 600232) as bait in a yeast 2-hybrid screen of a rat brain cDNA library, Beck et al. (2002) cloned rat Als2cr3, which they called Grif1. Northern blot analysis detected a major 6.2-kb transcript in all tissues tested except testis, which expressed a truncated transcript of 2.9 kb; a minor 4.2-kb transcript was also detected. Western blot analysis revealed tissue-specific expression of 3 Grif1 species with different molecular masses in brain, heart, and skeletal muscle. Grif1 was expressed in HEK293 cells as 3 proteins with apparent molecular masses of 98, 106, and 115 kD.
Beck et al. (2002) found that transfected rat Grif1 colocalized with GABA-A receptor subunits. Immobilized Grif1 specifically precipitated the alpha-1 (GABRA1; 137160) and beta-2 subunits of the GABA-A receptor from detergent extracts of adult rat brain.
Hadano et al. (2001) determined that the ALS2CR3 (TRAK2) gene contains 16 exons and spans more than 43 kb. It is transcribed in the telomere-to-centromere direction. The promoter for ALS2CR3 is close to, or overlaps, the promoter for ALS2CR2 (607333), which is transcribed in the opposite orientation.
Hadano et al. (2001) mapped the TRAK2 gene within the ALS2 critical region on chromosome 2q33-q34.
Beck, M., Brickley, K., Wilkinson, H. L., Sharma, S., Smith, M., Chazot, P. L., Pollard, S., Stephenson, F. A. Identification, molecular cloning, and characterization of a novel GABA-A receptor-associated protein, GRIF-1. J. Biol. Chem. 277: 30079-30090, 2002. [PubMed: 12034717] [Full Text: https://doi.org/10.1074/jbc.M200438200]
Hadano, S., Yanagisawa, Y., Skaug, J., Fichter, K., Nasir, J., Martindale, D., Koop, B. F., Scherer, S. W., Nicholson, D. W., Rouleau, G. A., Ikeda, J.-E., Hayden, M. R. Cloning and characterization of three novel genes, ALS2CR1, ALS2CR2, and ALS2CR3, in the juvenile amyotrophic lateral sclerosis (ALS2) critical region at chromosome 2q33-q34: candidate genes for ALS2. Genomics 71: 200-213, 2001. [PubMed: 11161814] [Full Text: https://doi.org/10.1006/geno.2000.6392]