Cytological characterization of the neocentric chromosome neoM3. (A) Immunofluorescence assay of the oat-maize neoM3 addition line using anti-CENH3 antibodies. The arrow points to the CENH3 signal on the neoM3 chromosome. (B) The neoM3 chromosome is identified by sequential genomic in situ hybridization (GISH) of the same metaphase cell using maize genomic DNA as a probe. (C) The two copies of maize chromosome 3 (arrows) in the oat-maize addition line OMA 3.01 are detected by FISH using a 8.7-kb DNA probe amplified from the distal region on the short arm. (D) Identification of the maize chromosomes in the same metaphase cell as assayed by GISH. (E) FISH mapping of the 8.7-kb DNA probe on the neoM3 chromosome. Note: The probe hybridizes to both ends of the neoM3 chromosome (arrows). (F) The identification of neoM3 in the same metaphase cell is confirmed by GISH. Bars, 10 μm.
