Chromosome painting using repetitive DNA sequences as probes for somatic chromosome identification in maize.
Study of the maize (Zea mays L.) somatic chromosomes (2n = 20) has been difficult because of a lack of distinguishing characteristics. To identify all maize chromosomes, a multicolor fluorescence in situ hybridization procedure was developed. The procedure uses tandemly repeated DNA sequences to generate a distinctive banding pattern for each of the 10 chromosomes. Fluorescence in situ hybridization screening trials of nonsubtracted or subtracted PCR libraries resulted in the isolation of microsatellite 1-26-2, subtelomeric 4-12-1, and 5S rRNA 2-3-3 clones. These three probes, plus centromeric satellite 4 (Cent4), centromeric satellite C (CentC), knob, nucleolus-organizing region (NOR), pMTY9ER telomere-associated sequence, and tandemly repeated DNA sequence 1 (TR-1) were used as a mixture for hybridization to root-tip chromosomes. All 10 chromosomes were identified by the banding and color patterns in the 14 examined lines. There was significant quantitative variation among lines for the knob, microsatellite, TR-1, and CentC signals. The same probe mixture identifies meiotic pachytene, late prophase I, and metaphase I chromosomes. The procedure could facilitate the study of chromosomal structure and behavior and be adapted for other plant species.
Kato
Akio
A
Division of Biological Sciences, Tucker Hall, University of Missouri, Columbia, MO 65211-7400.
Lamb
Jonathan C
JC
Birchler
James A
JA
D020223:Chromosome Painting / Q000379:methods*; D032461:Chromosomes, Plant / Q000235:genetics*; D015342:DNA Probes / Q000235:genetics*; D007621:Karyotyping; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D003313:Zea mays / Q000235:genetics*
D015342:DNA Probes