Abstract
Chromosomal repatterning is considered to be one of the main mechanisms for plant genome evolution. Here, we report the first cytogenetic evidence for the involvement of En/Spm transposons in ongoing chromosomal repatterning leading to the rise of new fertile genomic forms in a small, isolated, peripheral plant population. Cytogenetical screening of original individual plants of Aegilops speltoides Tausch, with different phenotypes revealed a wide spectrum of chromosomal abnormalities including extra chromosomes, chromosomal rearrangements, and variability in chromosomal position/number of 45S and 5S rDNA sites. Cytogenetic analysis of the dynamics of En/Spm transposons in meiosis indicates that: (i) this type of transposon is active during male gametogenesis; (ii) separately or in conjunction with rDNA they form clusters in the hot spots of large chromosomal rearrangements; (iii) appearance of at least part of the mobile rDNA sites in genome of Ae. speltoides are connected with meiotic activity of En/Spm transposons. PCR screening for the site-selected transposon insertions confirm the presence of combined fragments that consist partly of the sequence of En/Spm transposon and partly of 5S rDNA sequence.
| Original language | English |
|---|---|
| Pages (from-to) | 153-161 |
| Number of pages | 9 |
| Journal | Chromosome Research |
| Volume | 12 |
| Issue number | 2 |
| DOIs | |
| State | Published - 2004 |
Bibliographical note
Funding Information:The authors are most grateful to Abraham Korol for his helpful discussion. We thank Bernard Baum for providing the As5SDNAE probe and Elena Benavente for providing the pTa71 probe for experiments. We thank Dr Ahu Altinkut and Dr Imad Shams for their help in pTa71 probe cloning. This work was supported by grants from the Research Authority of the University of Haifa.
Keywords
- 45S rDNA
- 5S rDNA
- Aegilops speltoides
- Chromosomal rearrangements
- En/Spm transposons
- Meiosis
- Populations
- in situ hybridization
ASJC Scopus subject areas
- Genetics