HGNC Approved Gene Symbol: DAD1
Cytogenetic location: 14q11.2 Genomic coordinates (GRCh38): 14:22,564,907-22,589,224 (from NCBI)
DAD1 is a core component of the multisubunit oligosaccharyltransferase (OST; EC 2.4.1.119). OST catalyzes the transfer of preassembled high mannose oligosaccharides onto target asparagines of nascent polypeptide chains within the lumen of the endoplasmic reticulum (ER) (Sanjay et al., 1998).
Nakashima et al. (1993) studied a temperature-sensitive mutant cell line, tsBN7, that died by apoptosis following a shift to the nonpermissive temperature. The tsBN7 cell line had been derived from the hamster BHK21 cell line. The induced apoptosis was inhibited by a protein synthesis inhibitor, cycloheximide, but not by the BCL2 (151430) protein, which acts as a brake against programmed cell death. By DNA-mediated gene transfer, Nakashima et al. (1993) cloned a human DAD1 cDNA that complemented the tsBN7 mutation. The deduced 113-amino acid human DAD1 protein is hydrophobic and shares 100% amino acid identity with its hamster homolog. Northern blot analysis detected high expression of a 0.8-kb transcript in all tissues examined.
Nakashima et al. (1993) determined that the DAD1 gene contains 3 exons.
By fluorescence in situ hybridization using YACs containing the DAD1 gene, Yulug et al. (1995) mapped the gene to chromosome 14q11-q12. They inferred that the mouse homolog is probably located in the middle of mouse chromosome 14.
Nakashima et al. (1993) demonstrated that the hamster Dad1 gene is mutated in the tsBN7 cell line (gly38 to arg). The Dad1 protein disappeared in temperature-sensitive cells following a shift to the nonpermissive temperature, suggesting that loss of Dad1 triggered apoptosis.
Makishima et al. (1997) confirmed that loss of Dad1 function in tsBN7 cells caused a defect in N-glycosylation and resulted in apoptosis. However, tunicamycin, an inhibitor of N-glycosylation, did not induce apoptosis in either tsBN7 cells or the parental BHK21 cell line.
Kelleher and Gilmore (1997) identified DAD1 as a core component of the functional OST complex purified from the rough ER fraction of WI38 human fibroblasts and from canine and porcine pancreatic microsomes. In canine OST preparations, Dad1 was obtained in roughly equimolar amounts relative to the 3 other OST components, ribophorin I (RPN1; 180470), ribophorin II (RPN2; 180490), and Ost48 (DDOST; 602202). Protein crosslinking confirmed tight association of Dad1 with Ost48, ribophorin I, and ribophorin II. Protein digestion experiments showed that Dad1 was exposed on the cytoplasmic face of the rough ER.
Using Western blot analysis, Sanjay et al. (1998) showed that shifting tsBN7 cells to the nonpermissive temperature resulted in loss of Dad1 and Ost48 proteins and reduced ribophorin protein levels to about 50% of those found in cells at the permissive temperature. N-glycosylation of the ribophorins and a test secretory glycoprotein was seriously affected following loss of OST components. Sanjay et al. (1998) concluded that degradation of Dad1 at the nonpermissive temperature affects both the stability of Ost48 and ribophorins and results in functional inactivation of the OST complex.
Using a yeast 2-hybrid screen with a human B-cell cDNA library, Makishima et al. (2000) showed that DAD1 interacted with the C-terminal region of the antiapoptotic protein MCL1 (159552) and with the proapoptotic protein NIP3 (BNIP3; 603293). DAD1 did not interact with full-length MCL1 in yeast 2-hybrid assays, but the 2 full-length proteins coimmunoprecipitated from transfected COS cells.
Kelleher, D. J., Gilmore, R. DAD1, the defender against apoptotic cell death, is a subunit of the mammalian oligosaccharyltransferase. Proc. Nat. Acad. Sci. 94: 4994-4999, 1997. [PubMed: 9144178] [Full Text: https://doi.org/10.1073/pnas.94.10.4994]
Makishima, T., Nakashima, T., Nagata-Kuno, K., Fukushima, K., Iida, H., Sakaguchi, M., Ikehara, Y., Komiyama, S., Nishimoto, T. The highly conserved DAD1 protein involved in apoptosis is required for N-linked glycosylation. Genes Cells 2: 129-141, 1997. [PubMed: 9167970] [Full Text: https://doi.org/10.1046/j.1365-2443.1997.1070303.x]
Makishima, T., Yoshimi, M., Komiyama, S., Hara, N., Nishimoto, T. A subunit of the mammalian oligosaccharyltransferase, DAD1, interacts with Mcl-1, one of the bcl-2 protein family. J. Biochem. 128: 399-405, 2000. [PubMed: 10965038] [Full Text: https://doi.org/10.1093/oxfordjournals.jbchem.a022767]
Nakashima, T., Sekiguchi, T., Kuraoka, A., Fukushima, K., Shibata, Y., Komiyama, S., Nishimoto, T. Molecular cloning of a human cDNA encoding a novel protein, DAD1, whose defect causes apoptotic cell death in hamster BHK21 cells. Molec. Cell. Biol. 13: 6367-6374, 1993. [PubMed: 8413235] [Full Text: https://doi.org/10.1128/mcb.13.10.6367-6374.1993]
Sanjay, A., Fu, J., Kreibich, G. DAD1 is required for the function and the structural integrity of the oligosaccharyltransferase complex. J. Biol. Chem. 273: 26094-26099, 1998. [PubMed: 9748289] [Full Text: https://doi.org/10.1074/jbc.273.40.26094]
Yulug, I. G., See, C. G., Fisher, E. M. C. The DAD1 protein, whose defect causes apoptotic cell death, maps to human chromosome 14. Genomics 26: 433-435, 1995. Note: Erratum: Genomics: 28: 129 only, 1995. [PubMed: 7601483] [Full Text: https://doi.org/10.1016/0888-7543(95)80241-d]