Hr38 is expressed throughout third-instar larval and prepupal development (Fisk, 1995).
Expression of the Hr38 gene in Drosophila embryogenesis was analyzed using RNA (Northern) blots, and multiple mRNA species were observed even in high stringency hybridization experiments. A prominent 2-kb band (sometimes resolved as a doublet of ~1.8 and 2.0 kb) is present in all embryonic mRNA preparations. A ~4.0-kb species is very abundant in the late embryos (19-23 hr post-egg laying) but is also detectable at lower levels earlier, especially in 15-19-hr embryos. A ~5.0 species is the least abundant in embryogenesis but is clearly present in 15-19-hr embryos. Of the multiple developmentally regulated transcripts of Hr38, the ~4.0- and 5.0-kb species correspond in size and might be represented by the cDNA clones described above (cTK61 and cTK11, respectively). The pLF16 cDNA clone described by Fisk (1995) might be represented by the 1.8- or 2.0-kb transcript, depending on the length of the poly(A)+ tail. The 4.0-kb species and the 1.8-2.0-kb doublet were detected in Schneider's S2 cell line as well. All mRNAs of the Hr38 gene are of low abundance; blotting of purified poly(A)+ RNA and probing by antisense riboprobes was required to detect them. Moreover, it appears that at least the 4.0-kb species is unstable because it is enriched in S2 cells treated with cycloheximide; the ~2.0-kb bands are unaffected by cycloheximide (Kozlova, 1998).
To analyze the expression of the Hr38 gene during all stages of Drosophila development, advantage was taken of a more sensitive technique, RT-PCR, and primers were designed that would specifically amplify fragments corresponding to either the cTK61 or the cTK11 cDNA isoforms. A pair of common primers, flanking the fourth intron in the ligand binding domain, was used to amplify a fragment present in all three cDNA clones described so far. The Hr38 gene is expressed during most of Drosophila development but with some notable variations in quantity. The common fragment indicates that the combined Hr38 mRNAs are present in 0-8-hr embryos at very low levels, which are significantly elevated in late embryogenesis and through the larval stages. Transcript levels become notably enriched in pre-pupal and especially pupal stages, and are again somewhat reduced in adult flies. The mRNAs are absent from the ovaries, but relatively concentrated in third instar larval imaginal discs and brain complexes. The expression profiles for individual isoforms are consistent with the profile of the common fragment, but show some interesting variations: the pupal enrichment is most dramatic for the cTK11 isoform, and the adult has a substantial amount of cTK11 but virtually no cTK61 transcript. In overall terms, the cTK11 (~5.0 kb) isoform is enriched in pupae and adults relative to the cTK61 (~4.0 kb) isoform, which is more characteristic of the larvae (Kozlova, 1998).
Four alleles have been characterized of Hr38; these consist of a P-element enhancer trap line, l(2)02306, which shows exclusively epidermal staining in the late larval, pre-pupal and pupal stages, and three EMS-induced alleles. Hr38 alleles cause localized fragility and rupturing of the adult cuticle, demonstrating that Hr38 plays an important role in late stages of epidermal metamorphosis. The lethal phases of available EMS and P-element induced mutations indicate that Hr38 is important for late stages of metamorphosis; the haemolymph leakage and melanization phenotype suggest that all presently available alleles affect adult cuticle formation, possibly leading to incomplete sclerotization. In the three weaker alleles the defects appear to be specific to the thoracic cuticle of the leg joints, because abdominal and head structures are not visibly affected. Overall morphology of the mutant flies bearing the stronger EMS allele, including tanning of the bristles, is normal in Hr3856/Df(2)KetelRX32 hemizygotes at 80-90 hr after puparium formation. It is unlikely that these mutations represent complete loss-of-function alleles. The weak Hr3843 and Hr3857 alleles behave as hypomorphs in genetic assays, and both mRNA and Hr38 protein are still present in the Hr3856/Df(2)KetelRX32 hemizygous mutant animals. Therefore either a specific epidermal function of Hr38 is affected in these mutants, specific epidermal cells are most sensitive to altered levels of Hr38 expression, or Hr38 is dispensable in tissues other than epidermis (Kozlova, 1998).
Aarnisalo, P., Kim, C. H., Lee, J. W. and Perlmann, T. (2002). Defining requirements for heterodimerization between the retinoid X receptor and the orphan nuclear receptor Nurr1. J. Biol. Chem. 277(38): 35118-23. 12130634
Baker, K. D., Warren, J. T., Thummel, C. S., Gilbert, L. I. and Mangelsdorf, D. J. (2000). Transcriptional activation of the Drosophila ecdysone receptor by insect and plant ecdysteroids. Insect Biochem. Mol. Biol. 30: 1037-1043. 10989290
Baker, K. D., et al. (2003). The Drosophila orphan nuclear receptor DHR38 mediates an atypical ecdysteroid signaling pathway. Cell 113: 731-742. 12809604
Bashirullah, A., Pasquinelli, A. E., Kiger, A. A., Perrimon, N., Ruvkun, G. and Thummel, C. S. (2003). Coordinate regulation of small temporal RNAs at the onset of Drosophila metamorphosis. Dev. Biol. 259(1): 1-8. 12812783
Billas, I. M. L., Moulinier, L., Rochel, N. and Moras, D. (2001). Crystal structure of the ligand-binding domain of the Ultraspiracle protein USP, the ortholog of retinoid X receptors in insects. J. Biol. Chem. 276: 7465-7474. 11171988
Castro, D. S., Arvidsson, M., Bolin, M. B. and Perlmann, T. (1999). Activity of the Nurrl carboxyl-terminal domain depends on cell type and integrity of the activation function 2. J. Biol. Chem. 274: 37483-37490. 10601324
Cheng, L. E., Chan, F. K., Cado, D. and Winoto, A. (1997). Functional redundancy of the Nur77 and Nor-1 orphan steroid receptors in T-cell apoptosis. EMBO J. 16, 1865-1875. 9155013
Clayton, G. M., Peak-Chew, S. Y., Evans, R. M. and Schwabe, J. W. R. (2001). The structure of the ultraspiracle ligand-binding domain reveals a nuclear receptor locked in an inactive conformation. Proc. Natl. Acad. Sci. USA 98, 1549-1554. 11053444
Fisk, G. J., et al. (1995). Isolation, regulation, and DNA-binding properties of three Drosophila nuclear hormone receptor superfamily members. Proc. Natl. Acad. Sci. 92: 10604-10608. 7479849
Forman, B. M., Umesono, K., Chen, J. and Evans, R. M. (1995). Unique response pathways are established by allosteric interactions among nuclear hormone receptors. Cell 81(4): 541-50. 7758108
Giguere, V. (1999). Orphan nuclear receptors: from gene to function. Endocr. Rev. 20: 689-725. 10529899
Gruber, F., et al. (2003). Direct binding of Nur77/NAK-1 to the plasminogen activator inhibitor 1 (PAI-1) promoter regulates TNF alpha -induced PAI-1 expression. Blood 101(8):3042-8. 12506026
Hall, B. L. and Thummel, C. S. (1998). The RXR homolog Ultraspiracle is an essential component of the Drosophila ecdysone receptor. Development 125: 4709-4717. 9806919
Katagiri, Y., Hirata, Y., Milbrandt, J. and Guroff, G. (1997). Differential regulation of the transcriptional activity of the orphan nuclear receptor NGFI-B by membrane depolarization and nerve growth factor. J. Biol. Chem. 272(50): 31278-84. 9395454
Kim, S. O., Ono, K., Tobias, P. S. and Han, J. (2003). Orphan nuclear receptor Nur77 is involved in caspase-independent macrophage cell death. J. Exp. Med. 197(11): 1441-52. 12782711
King-Jones, K., Horner, M. A., Lam, G. and Thummel, C. S. (2006). The DHR96 nuclear receptor regulates xenobiotic responses in Drosophila. Cell Metab. 4: 37-48. Medline abstract: 16814731
Komonyi, O., Mink, M., Csiha, J. and Maroy, P. (1996). Genomic organization of Hr38 gene in Drosophila: presence of Alu-like repeat in a translated exon and expression during embryonic development. Arch. Insect Biochem. Physiol. 38(4): 185-92. 9704500
Kozlova, T., et al. (1998). Drosophila Hormone receptor 38 functions in metamorphosis: A role in adult cuticle formation. Genetics 149: 1465-1475. 9649534
Kozlova, T., et al. (2002). Spatial patterns of ecdysteroid receptor activation during the onset of Drosophila metamorphosis. Development 129: 1739-1750. 11923209
Liu, D., Jia, H., Holmes, D. I., Stannard, A. and Zachary, I. (2003). Vascular endothelial growth factor-regulated gene expression in endothelial cells. KDR-mediated induction of Egr3 and the related nuclear receptors Nur77, Nurr1, and Nor1. Arterioscler. Thromb. Vasc. Biol. 23(11): 2002-7. 14525795
Maira, M., Martens, C., Batsche, E., Gauthier, Y. and Drouin, J. (2003). Dimer-specific potentiation of NGFI-B (Nur77) transcriptional activity by the protein kinase A pathway and AF-1-dependent coactivator recruitment. Mol. Cell. Biol. 23(3):763-76. 12529383
Masuyama, N., Oishi, K., Mori, Y., Ueno, T., Takahama, Y. and Gotoh, Y. (2001). Akt inhibits the orphan nuclear receptor Nur77 and T-cell apoptosis. J. Biol. Chem. 276(35): 32799-805. 11438550
Ordentlich, P., Yan, Y., Zhou, S. and Heyman, R. A. (2003). Identification of the antineoplastic agent 6-mercaptopurine as an activator of the orphan nuclear hormone receptor Nurr1. J. Biol. Chem. 278(27): 24791-9. 12709433
Palanker, L., et al. (2006). Dynamic regulation of Drosophila nuclear receptor activity in vivo. Development 133(18): 3549-62. Medline abstract: 16914501
Paulsen, R. F., Granas, K., Johnsen, H., Rolseth, V. and Sterri, S. (1995). Three related brain nuclear receptors, NGFI-B, Nurr1, and NOR-1, as transcriptional activators. J. Mol. Neurosci. 6: 249-255. 8860236
Pekarsky, Y., et al. (2001). Akt phosphorylates and regulates the orphan nuclear receptor Nur77. Proc. Natl. Acad. Sci. 98(7): 3690-4. 11274386
Perlmann, T. and Jansson, L. (1995). A novel pathway for vitamin A signaling mediated by RXR heterodimerization with NGFI-B and NURR1. Genes Dev. 9: 769-782. 7705655
Philips, A., Lesage, S., Gingras, R., Maira, M. H., Gauthier, Y., Hugo, P. and Drouin, J. (1997). Novel dimeric Nur77 signaling mechanism in endocrine and lymphoid cells. Mol. Cell. Biol. 17: 5946-5951. 9315652
Sirin, O., et al. (2010). The orphan nuclear receptor Nurr1 restricts the proliferation of haematopoietic stem cells. Nat. Cell Biol. 12(12): 1213-9. PubMed Citation: 21076412
Sutherland, J. D., Kozlova, T., Tzertzinis, G. and Kafatos, F. C. (1995). Drosophila hormone receptor 38: a second partner for Drosophila Usp suggests an unexpected role for nuclear receptors of the nerve growth factor-induced protein B type. Proc. Natl. Acad. Sci. 92(17): 7966-70. 7644522
Suzuki, S., et al. (1995). Nur77 as a survival factor in tumor necrosis factor signaling. Proc. Natl. Acad. Sci. 100(14): 8276-80. 12815108
Wansa, K. D., Harris, J. M. and Muscat, G. E. (2002). The activation function-1 domain of Nur77/NR4A1 mediates trans-activation, cell specificity, and coactivator recruitment. J. Biol. Chem. 277(36): 33001-11. 12082103
Wansa, K. D., Harris, J. M., Yan, G., Ordentlich, P. and Muscat, G. E. (2003). The AF-1 domain of the orphan nuclear receptor NOR-1 mediates trans-activation, coactivator recruitment, and activation by the purine anti-metabolite 6-mercaptopurine. J. Biol. Chem. 278(27): 24776-90. 12709428
Wilson, T. E., Fahrner, T. J., Johnston, M. and Milbrandt, J. (1991). Identification of the DNA binding site for NGFI-B by genetic selection in yeast. Science 252: 1296-1300. 1925541
Zetterstrom, R. H., Solomin, L., Mitsiadis, T., Olson, L. and Perlmann T. (1996). Retinoid X receptor heterodimerization and developmental expression distinguish the orphan nuclear receptors NGFI-B, Nurr1, and Nor1. Mol. Endocrinol. 10(12): 1656-66. 8961274
date revised: 5 August 2011
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