| First Author | Klett C | Year | 1991 |
| Journal | Mouse Genome | Volume | 89 |
| Pages | 275 | Mgi Jnum | J:14305 |
| Mgi Id | MGI:62476 | Citation | Klett C, et al. (1991) Mapping of Nmyc-1 to mouse Chromosome 12, band A3/B. Mouse Genome 89:275 |
| abstractText | Full text of Mouse Genome contribution: MAPPING OF Nmyc-1 TO MOUSE CHROMOSOME 12, BAND A3/B. Christine Klett1, Sabine Adolph1,2, Uhlrike Hirning1; 1 Abt f. Kiln. Genetik, Albert-Einstein-Allee 11, D-7900 Ulm, FRG; 2 present address: Inst. f. Humangenetik, Bahnhofstr. 7A D-3550 Marburg, FRG INTRODUCTION The neuroblastoma myc-related oncogene-1, Nmyc-1, resides in a linkage group of 7 genes syntenic to human chromosome 2 (1). The human genes are located near the telomere of the short arm in band 2p23 to 2p25; MYCN, the human counterpart to Nmyc-1 has been localized to band 2p24. In the mouse this linkage group has not been physically assigned. Only three genes, Pomc-1, Apob and Odc are genetically mapped to the proximal end of chromosome 12 (2). In order to start to anchor this large linkage group physically to chrom. 12 we localized Nmyc-1 by in situ hybridisation. MATERIALS AND METHODS Chromosomes of embryo fibroblast cells of Rb(4.12)9Bnr mice, which carry chrom. 12 as the only metacentric chromosome pair, were prepared by the standard technique. Chromosomes of the erythro-leukemia cell line MEL (3) were also included in the analysis. The in situ hybridization was performed as described previously (4). The DNA probe for Nmyc-1 was p277.3 (5). Silver staining was done according to Howell & Black (6). RESULTS A total of 61 silver grains were assigned over 28 metaphases from embryo fibroblast cells; 27 silver grains were found on chrom. 12, and 18 (29%) of them were specifically assigned to band A3/B (Fig. 1). In MEL cells one copy of chrom. 12 is fused with chrom. 6, Rb(6.12), the other chrom. 12 expresses a strong secondary constriction in band A2, due to a very active NO-site (strongly silver positive). In this cell line a total of 121 silver grains were assigned over 50 metaphases; 76 grains were found on chrom. 12 (44 on the metacentric chrom. 12, and 32 on the acrocentric one). Of these, 59 grains were specific for the border of the bands A3 and B, distal to the secondary constriction. Fig. 1. (Legend). Distribution of silver grains over mouse chromosome 12 after in situ hybridisation with the Nmyc-1 probe, p277.3. To the left the grain distribution on the metacentric chromosomes, Rb(6.12) of MEL (white bars) and Rb(4.12)9Bnr (black bars) is given; to the right the grain distribution on the acrocentric chrom. 12 in MEL is presented. The inset shows the acrocentric chrom. 12 in MEL cells; from left to right: G-banding, Nmyc-1 signal after in situ hybridisation and silver staining at the NO-site. DISCUSSION Two large linkage groups on murine chrom. 12 are syntenic to man. One is located in the distal half and includes at least 7 loci surrounding Fos, Aat, and the Igh genes (2). They map to human chrom. 14, band 14q24-14q32 (7). The other linkage group comprises also 7 genes, but is not that well analysed. Genetic mapping data assigned only Pomc-1, Apob and Odc next to the proximal end of chrom. 12. Our data suggest that this linkage group is indeed located at the proximal end of chrom. 12 with Nmyc-1 distal to the secondary constriction at the border of band A3 and B. On human chromosomes MYCN is mapped to the G-band 2p24 which might correspond to 12A3 in mouse. REFERENCES 1 Lalley et al. (1989) Human Gene Mapping 10:514 2 Lyon & Kirby (1990) Mouse Genome 87:40 Lusis et al. (1987) J Biol Chem 258:1540 3 Miller et al. (1979) Cancer Genet Cytogenet 1:103-113 4 Adolph et al. (1987) Cytogenet Cell Genet 44:65-68 5 DePinho et al. (1986) Proc. Nat. Acad. Sci. 83:1827-1831 6 Howell & Black (1985) Experientia 36:1014. 7 Lalley et al. (1989) Human Gene Mapping 10:518 |
