Alternative titles; symbols
HGNC Approved Gene Symbol: GET3
Cytogenetic location: 19p13.13 Genomic coordinates (GRCh38): 19:12,737,106-12,748,323 (from NCBI)
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
|---|---|---|---|---|
| 19p13.13 | ?Cardiomyopathy, dilated, 2H | 620203 | Autosomal recessive | 3 |
ASNA1 is the human homolog of the bacterial arsA gene. In E. coli, ArsA ATPase is the catalytic component of a multisubunit oxyanion pump that is responsible for resistance to arsenicals and antimonials.
Kurdi-Haidar et al. (1996) used degenerate PCR to clone a human homolog of the bacterial arsA gene. The human ARSA1 cDNA was isolated from a human ovarian carcinoma library and found to encode a 332-amino acid polypeptide having an N-terminal ATP-binding cassette (ABC) domain and a C-terminal domain of unknown function. The protein sequence is highly homologous throughout both domains to hypothetical arsA proteins of C. elegans and yeast. Northern blot analysis revealed that the ARSA1 gene is ubiquitously expressed. Southern blot analysis indicated the existence of 2 closely related ARSA genes in the human genome. The existence of a second human ARSA protein was further supported by Western blot analysis, which demonstrated that anti-ARSA1 antibodies identify 2 proteins of 37 and 42 kD. Kurdi-Haidar et al. (1996) expressed ARSA1 and found that the resulting 37-kD protein had ATPase activity.
Kurdi-Haidar et al. (1998) found that ASNA1 shows a cytoplasmic, perinuclear, and nucleolar distribution. By cell fractionation and extensive use of double-label immunolocalizations, they demonstrated that the cytoplasmic protein was soluble, the perinuclear protein was associated with invaginations of the nuclear membranes rather than with the endoplasmic reticulum, and that the nucleolar signal colocalized with known nucleolar markers. Bhattacharjee et al. (2001) cloned mouse Asna1 which encodes a 348-amino acid protein sharing 27% and 99% identity with the E. coli and human proteins, respectively. Northern blot analysis detected a 1.3-kb transcript in mouse at highest levels in kidney and testis, moderate levels in brain, liver, lung, and skin, low levels in heart, small intestine, spleen, stomach, and thymus, and negligible levels in skeletal muscle.
Kurdi-Haidar et al. (1998) determined that the ASNA1 gene contains 4 exons and spans 6 kb. Bhattacharjee et al. (2001) determined that the mouse Asna1 gene consists of 7 exons spanning over 7 kb.
By somatic cell hybrid PCR mapping and identification of a cosmid containing the full-length sequence, Kurdi-Haidar et al. (1998) mapped the ASNA1 gene to chromosome 19q13.3. Bhattacharjee et al. (2001) mapped the mouse Asna1 gene to the C3-D1 region of chromosome 8.
Kurdi-Haidar et al. (1998) characterized purified recombinant ASNA1. They determined that the ATPase activity increases in the presence of sodium arsenite and that Vmax rather than ATP affinity is enhanced. Unlike the E. coli homolog in which arsenite or antimonite allosterically activates arsA ATPase activity, potassium antimonite had no effect on the ATPase activity of human ASNA1. Through chemical crosslinking of recombinant protein and by nonreducing PAGE analysis of ASNA1 overexpressed in human kidney cells, they found that the active species is likely a dimer or tetramer.
Mariappan et al. (2010) identified a conserved 3-protein complex composed of BAT3 (142590), TRC35 (GET4; 612056), and UBL4A (312070) that facilitates tail-anchored protein capture by TRC40. This BAT3 complex is recruited to ribosomes synthesizing membrane proteins, interacts with the transmembrane domains of newly released tail-anchored proteins, and transfers them to TRC40 for targeting. Depletion of the BAT3 complex allows non-TRC40 factors to compete for tail-anchored proteins, explaining their mislocalization in the analogous yeast deletion strains. Thus, the BAT3 complex acts as a transmembrane domain-selective chaperone that effectively channels tail-anchored proteins to the TRC40 insertion pathway.
Using binding assays, Chartron et al. (2010) found that yeast Get4/Get5 (UBL4A) formed a complex with Get3, with Get3 specifically binding to the conserved surface of Get4 in a nucleotide-dependent manner.
To understand how the fate of nascent tail-anchored membrane proteins is determined, Shao et al. (2017) reconstituted the core reactions for membrane targeting and ubiquitination of these proteins. They found that the central 6-component triage system is divided into an uncommitted client-SGTA (603419) complex, a self-sufficient targeting module, and an embedded but self-sufficient quality control module. Client-SGTA engagement of the targeting module induced rapid, private, and committed client transfer to TRC40 for successful biosynthesis. Commitment to ubiquitination is dictated primarily by comparatively slower client dissociation from SGTA and nonprivate capture by the BAG6 (142590) subunit of the quality control module. Shao et al. (2017) concluded that their results provided a paradigm for how priority and time are encoded within a multichaperone triage system.
In 2 sibs with dilated cardiomyopathy-2H (CMD2H; 620203), Verhagen et al. (2019) identified compound heterozygous mutations in the GET3 gene (Q305X and C289W in cis, 601913.0001; V163A, 601913.0002). The mutations were identified by whole-exome sequencing. ASNA1 protein expression was reduced in cardiac tissue from both sibs and was reduced in fibroblasts from one of the sibs. ASNA1 with the V163A mutation was inefficiently folded due to abnormal aggregation and had reduced insertion into ER microsomes compared to wildtype ASNA1.
Mukhopadhyay et al. (2006) generated Asna1 knockout mice. Embryonic lethality occurred in homozygous knockout mice between embryonic days E3.5-E8.5, whereas heterozygous mutant mice were similar to wildtype mice.
Verhagen et al. (2019) generated asna1 knockout zebrafish models. The mutant zebrafish embryos had impaired swim bladder inflation and reduced body size. Starting on 5 days postfertilization, the mutant zebrafish exhibited abnormal cardiac contractions with decreased fractional shortening. The mutant hearts also had irregular shape and thin walls. Injection of wildtype ASNA1 into mutant zebrafish embryos rescued the abnormal cardiac phenotype, whereas injection with ASNA1 with the V163A (601913.0002) did not rescue the phenotype.
In 2 sibs with dilated cardiomyopathy-2H (CMD2H; 620203), Verhagen et al. (2019) identified compound heterozygous mutations in the GET3 gene: a c.913C-T transition (c.913C-T, NM_004317.2), resulting in a gln305-to-ter (Q305X) substitution, in cis with a c.867C-G transversion, resulting in a cys289-to-trp (C289W) substitution, and a c.488T-C transition, resulting in a val163-to-ala (V163A; 601913.0002) substitution. The mutations were identified by whole-exome sequencing, and the parents were shown to be mutation carriers. The mutations were not present in the gnomAD database (v2.0.2). ASNA1 protein expression was reduced in cardiac tissue from both sibs and in fibroblasts from one of the sibs.
For discussion of the c.488T-C transition (c.488T-C, NM_004317.2) in the GET3 gene, resulting in a val163-to-ala (V163A) substitution, that was identified in sibs with dilated cardiomyopathy-2H (CMD2H; 620203) by Verhagen et al. (2019), see 601913.0001.
Bhattacharjee, H., Ho, Y.-S., Rosen, B. P. Genomic organization and chromosomal localization of the Asna1 gene, a mouse homologue of a bacterial arsenic-translocating ATPase gene. Gene 272: 291-299, 2001. [PubMed: 11470536] [Full Text: https://doi.org/10.1016/s0378-1119(01)00522-4]
Chartron, J. W., Suloway, C. J., Zaslaver, M., Clemons, W. M. Structural characterization of the Get4/Get5 complex and its interaction with Get3. Proc. Nat. Acad. Sci. 107: 12127-12132, 2010. [PubMed: 20554915] [Full Text: https://doi.org/10.1073/pnas.1006036107]
Kurdi-Haidar, B., Aebi, S., Heath, D., Enns, R. E., Naredi, P., Hom, D. K., Howell, S. B. Isolation of the ATP-binding human homolog of the arsA component of the bacterial arsenite transporter. Genomics 36: 486-491, 1996. [PubMed: 8884272] [Full Text: https://doi.org/10.1006/geno.1996.0494]
Kurdi-Haidar, B., Heath, D., Aebi, S., Howell, S. B. Biochemical characterization of the human arsenite-stimulated ATPase (hASNA-I). J. Biol. Chem. 273: 22173-22176, 1998. [PubMed: 9712828] [Full Text: https://doi.org/10.1074/jbc.273.35.22173]
Kurdi-Haidar, B., Heath, D., Lennon, G., Howell, S. B. Chromosomal localization and genomic structure of the human arsenite-stimulated ATPase (hASNA-I). Somat. Cell Molec. Genet. 24: 307-311, 1998. [PubMed: 10696239] [Full Text: https://doi.org/10.1023/b:scam.0000007134.16744.8b]
Kurdi-Haidar, B., Hom, D. K., Flittner, D. E., Heath, D., Fink, L., Naredi, P., Howell, S. B. Dual cytoplasmic and nuclear distribution of the novel arsenite-stimulated human ATPase (hASNA-I). J. Cell. Biochem. 71: 1-10, 1998. [PubMed: 9736449]
Mariappan, M., Li, X., Stefanovic, S., Sharma, A., Mateja, A., Keenan, R. J., Hegde, R. S. A ribosome-associating factor chaperones tail-anchored membrane proteins. Nature 466: 1120-1124, 2010. [PubMed: 20676083] [Full Text: https://doi.org/10.1038/nature09296]
Mukhopadhyay, R., Ho, Y. S., Swiatek, P. J., Rosen, B. P., Bhattacharjee, H. Targeted disruption of the mouse Asna1 gene results in embryonic lethality. FEBS Lett. 580: 3889-3894, 2006. [PubMed: 16797549] [Full Text: https://doi.org/10.1016/j.febslet.2006.06.017]
Shao, S., Rodrigo-Brenni, M. C., Kivlen, M. H., Hegde, R. S. Mechanistic basis for a molecular triage reaction. Science 355: 298-302, 2017. [PubMed: 28104892] [Full Text: https://doi.org/10.1126/science.aah6130]
Verhagen, J. M. A., van den Born, M., van der Linde, H. C., Nikkels, P. G. J., Verdijk, R. M., Kivlen, M. H., van Unen, L. M. A., Baas, A. F., ter Heide, H., van Osch-Gevers, L., Hoogeveen-Westerveld, M., Herkert, J. C., and 10 others. Biallelic variants in ASNA1, encoding a cytosolic targeting factor of tail-anchored proteins, cause rapidly progressive pediatric cardiomyopathy. Circ. Genom. Precis. Med. 12: 397-406, 2019. Note: Erratum: Circ. Genom. Precis. Med. 13: e000065, 2020. [PubMed: 31461301] [Full Text: https://doi.org/10.1161/CIRCGEN.119.002507]