THE PHYSICAL LOCATION OF GENES CDC2 AND PRH1 IN MAIZE (ZEA-MAYS L.)

A biotin-labelling in situ hybridization technique was first used to p hysically map two single copy genes, cdc2 and prh1, in maize. These tw o genes are metabolically interrelated genes. The full-length cDNA clo nes cdc2ZmA and ZmPPI of genes cdc2 and prh1 were adopted as the probe s. They are 1.3 and 1.6 kb in size, respectively. Clone cdc2ZmA was ph ysically mapped on the long arm of chromosomes 4, 8, and 9. The percen t distances From centromere to detection sire were 57.9 +/- 2.7, 28.4 +/- 1.5, and 88.2 +/- 3.3. The detection rate was 19.2%. Clone ZmPP1 w as physically mapped on the long arm of chromosomes 4, 6, and 8. The p ercent distances were 53.6 +/- 1.2, 60.8 +/- 2.9 and 17.1 +/- 1.6. The detection ratio was 18.5%. The technique of chromosome ISH and the re lationship between the location and function of these two genes have b een discussed.