Mammalian Apoptosis-Associated Genes c-myc and p53 in Maize : Homologs and Their Locations

The highly conserved proto-oncogene c-myc and tumor suppressor gene p53 in animals has been shown to play a central role in regulating multiple developmental processes including growth, proliferation and differentiation, and are also 2 of the important genes associated with programmed cell death. Using the probes corresponding to the 2 genes derived from human, we detected and localized their DNA homologs in maize (<I>Zea mays</I> L.) at cytogenetic level for the first time utilizing chromosome <I>in situ</I> hybridization. For detection, techniques, 3, 3'-diaminobenzidine and fluorescence staining were utilized. Both of them gave the identical results. The signals of the test probe corresponding to c-myc were detected on 4L (the long arm of chromosome 4) and 5L and 1S (the short arm of chromosome 1) simultaneously. And those of p53 were localized on 5S, 1L, 3L and 9L simultaneously. These results further confirmed the existence of the homologs of the 2 genes in maize at DNA level. The improvements of FISH technique using heterologous probes were discussed.