Centromere-Specific Single-Copy Sequences of Secale Species

Area of Science:

• Genetics
• Molecular Biology
• Cytogenetics

Background:

• Single-copy fluorescence in situ hybridization (FISH) is crucial for mapping DNA sequences to chromosomes.
• Centromeric sequences are key to understanding centromere structure and variations.
• Rye (Secale cereale L.) chromosomes present complex structures relevant to crop improvement.

Purpose of the Study:

• To clone and characterize novel centromeric single-copy sequences from rye.
• To utilize these sequences for precise centromere localization in rye and wheat-rye translocations.
• To investigate structural differences in centromeric regions of wheat-rye translocation chromosomes.

Main Methods:

• Cloning of nine centromeric single-copy sequences from Secale cereale L.
• Fluorescence in situ hybridization (FISH) using cloned sequences as probes.
• Sequence similarity analysis across Secale species.
• Integration with rye genomic data to analyze wheat-rye translocations.

Main Results:

• Nine centromeric single-copy sequences (1R1, 3R1, 4R1, 4R2, 5R1, 5R2, 6R2, 6R3, 7R1) were successfully identified and mapped to specific rye chromosome centromeres.
• High sequence similarity of these centromeric sequences was observed among different Secale species.
• FISH analysis precisely identified the centromeric segment of rye chromosome 1R within specific 1BL.1RS translocations in wheat cultivars.

Conclusions:

• The nine cloned centromeric single-copy sequences are effective tools for determining centromere locations on rye chromosomes.
• These sequences can accurately reveal structural variations in centromeres of wheat-rye centric fusion translocation chromosomes.
• Further discovery of centromeric single-copy sequences is warranted for comprehensive cytogenetic analysis.