scholarly journals Nuclear dispositions of subtelomeric and pericentromeric chromosomal domains during meiosis in asynaptic mutants of rye (Secale cereale L.)

2001 ◽  
Vol 114 (10) ◽  
pp. 1875-1882 ◽  
Author(s):  
E.I. Mikhailova ◽  
S.P. Sosnikhina ◽  
G.A. Kirillova ◽  
O.A. Tikholiz ◽  
V.G. Smirnov ◽  
...  
Keyword(s):  
Secale Cereale ◽  
Meiotic Prophase ◽  
Male Meiosis ◽  
Subsequent Stage ◽  
Centromeric Sequence ◽  
Tapetal Cells ◽  
Secale Cereale L ◽  
Mother Cells ◽  
Subtelomeric Regions

The nuclear dispositions of subtelomeric and pericentromeric domains in pollen mother cells (PMCs) were tracked during meiosis in wildtype and two asynaptic mutants of rye (Secale cereale L.) by means of fluorescence in situ hybridization (FISH). Homozygotes for sy1 and sy9 non-allelic mutations form axial elements during leptotene of male meiosis, but fail to form synaptonemal complexes. Consequently, recombination is severely impaired, and high univalency is observed at metaphase I. Simultaneous FISH with pSc200 subtelomeric tandem repeat and CCS1 centromeric sequence revealed that at pre-meiotic interphase the two domains are in a bipolar Rabl orientation in both the PMCs and tapetal cells. At the onset of meiotic prophase, the subtelomeric regions in PMCs of wildtype and sy9 cluster into a typical bouquet conformation. The timing of this event in rye is comparable with that in wheat, and is earlier than that observed in other organisms, such as maize, yeast and mammals. This arrangement is retained until later in leptotene and zygotene when the pericentromeric domains disperse and the subtelomeric clusters fragment. The mutant phenotype of sy9 manifests itself during leptotene to zygotene, when the pericentromeric regions become distinctly more distended than in wildtype, and largely fail to pair during zygotene. This indicates that difference in the nature or timing of chromosome condensation in this region is the cause or consequence of asynapsis. By contrast, sy1 fails to form comparable aggregates of subtelomeric regions at leptotene in only half of the nuclei studied. Instead, two to five aggregates are formed that fail to disperse at later stages of meiotic prophase. In addition, the pericentromeric regions disperse prematurely at leptotene and do not associate in pairs at any subsequent stage. It is supposed that the sy1 mutation could disrupt the nuclear disposition of centromeres and telomeres at the end of pre-meiotic interphase, which could cause, or contribute to, its asynaptic phenotype.

Autoradiography of Soluble [2-14C]Thymidine Derivatives During Meiosis And Microsporogenesis in Lilium Anthers

1967 ◽  
Vol 2 (3) ◽  
pp. 387-400 ◽  
Author(s):  
J. HESLOP-HARRISON ◽  
A. MACKENZIE
Keyword(s):  
Meiotic Prophase ◽  
Trichloroacetic Acid ◽  
Thymidine Incorporation ◽  
Callose Wall ◽  
Autoradiographic Method ◽  
Tapetal Cells ◽  
Mother Cells

A dry autoradiographic method suitable for locating soluble tracers has been used to follow the fate of [2-14C]thymidine supplied to detached buds and inflorescences of Lilium henryi and a related cultivar. During the interval from the archesporial phase until pachytene, the derivative (or derivatives) reaching the anther loculi moved freely into the meiocytes. Subsequently, the tracer was excluded from the mother cells until the dissolution of the tetrads. The young spores readily took up tracer in the thecal fluid upon their release, and yielded strongly localized autoradiographs. These observations are interpreted as indicating that access of materials to the meiocytes is related to the formation of cytoplasmic links between mother cells in the early meiotic prophase, and the later severance of these links through the growth of the isolating callose wall which comes to invest the tetrads. Judged from the tracer retained in preparations extracted with trichloroacetic acid, thymidine incorporation occurs mostly in the premeiotic and early leptotene period, although there is some slight evidence of incorporation later in prophase. In the tapetal cells, incorporation occurred in most of the stages tested, but there was no indication of a transfer of labelled materials from tapetum to spores in the post-meiotic period.

Analysis and sorting of rye (Secale cereale L.) chromosomes using flow cytometry

Genome ◽  
2003 ◽  
Vol 46 (5) ◽  
pp. 893-905 ◽  
Author(s):  
M Kubaláková ◽  
M Valárik ◽  
J Bartoš ◽  
J Vrána ◽  
J Cíhalíková ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Physical Mapping ◽  
Secale Cereale ◽  
B Chromosomes ◽  
Addition Lines ◽  
Large Numbers ◽  
Secale Cereale L

Procedures for chromosome analysis and sorting using flow cytometry (flow cytogenetics) were developed for rye (Secale cereale L.). Suspensions of intact chromosomes were prepared by mechanical homogenization of synchronized root tips after mild fixation with formaldehyde. Histograms of relative fluorescence intensity obtained after the analysis of DAPI-stained chromosomes (flow karyotypes) were characterized and the chromosome content of the DNA peaks was determined. Chromosome 1R could be discriminated on a flow karyotype of S. cereale 'Imperial'. The remaining rye chromosomes (2R–7R) could be discriminated and sorted from individual wheat–rye addition lines. The analysis of lines with reconstructed karyotypes demonstrated a possibility of sorting translocation chromosomes. Supernumerary B chromosomes could be sorted from an experimental rye population and from S. cereale 'Adams'. Flow-sorted chromosomes were identified by fluorescence in situ hybridization (FISH) with probes for various DNA repeats. Large numbers of chromosomes of a single type sorted onto microscopic slides facilitated detection of rarely occurring chromosome variants by FISH with specific probes. PCR with chromosome-specific primers confirmed the identity of sorted fractions and indicated suitability of sorted chromosomes for physical mapping. The possibility to sort large numbers of chromosomes opens a way for the construction of large-insert chromosome-specific DNA libraries in rye.Key words: chromosome isolation, chromosome sorting, fluorescence in situ hybridization, repetitive DNA sequences, wheat-rye addition lines, B chromosomes, physical mapping.

Banding of rye (Secale cereale) chromosomes using the restriction enzymes AluI, DraI, HpaII, and MspI

Genome ◽  
1993 ◽  
Vol 36 (5) ◽  
pp. 998-1002 ◽  
Author(s):  
T. Stößer ◽  
T. Günther ◽  
C. U. Hesemann
Keyword(s):  
Secale Cereale ◽  
Restriction Enzymes ◽  
Chromosome Band ◽  
Banding Technique ◽  
Recognition Sequence ◽  
Metaphase Chromosomes ◽  
Banding Patterns ◽  
Secale Cereale L ◽  
Characteristic Banding

Mitotic metaphase chromosomes of the rye inbred line L 301, which belongs to the Sortiment of the University of Hohenheim, were treated in situ with the restriction enzymes AluI (recognition sequence: 5′-AC/GT-3′), DraI (recognition sequence: 5′-TTT/AAA-3′), and the isoschizomeres HpaII and MspI (recognition sequence: 5′-C/CGG-3′) and stained with Giemsa. The chromosomes indicated similar banding patterns in comparison with the conventional Giemsa-C-banding. However, we have found in rye chromosomes after restrictase treatment that the telomeric bands were reduced in extension. In a lower degree the centromeric bands of individual chromosomes could be absent in dependence of the used restriction enzymes. The number of the intercalary bands were also reduced. Nevertheless, the tested restriction enzymes produced characteristic banding patterns of the rye genome. This uncomplicated banding technique is suited for a very quick banding method of karyotype analysis especially to obtain a first survey of the band patterns on the rye chromosomes.Key words: Secale cereale L., chromosome band pattern, in situ digestion, restriction endonuclease, restriction banding.

THE INHERITANCE OF RYE CHROMOSOMES IN EARLY GENERATIONS OF TRITICALE × WHEAT HYBRIDS

1982 ◽  
Vol 24 (3) ◽  
pp. 285-291 ◽  
Author(s):  
C. E. May ◽  
R. Appels
Keyword(s):  
Triticum Aestivum ◽  
Secale Cereale ◽  
Second Generation ◽  
Triticum Aestivum L ◽  
Chromosome Translocation ◽  
Agronomic Characters ◽  
Secale Cereale L ◽  
Wheat Hybrids ◽  
Triticosecale Wittmack

Triticales (× Triticosecale Wittmack) are being employed as a source of rye (Secale cereale L.) chromatin for the introduction of specific agronomic characters into wheat (Triticum aestivum L. em Thell.). The rye chromosomes present in plants of the first and second generations of a backcrossing program have been identified using a radioactive in situ probe which hybridizes to specific sites on the rye chromosomes. We show that homologous pairs of rye chromosomes are present by the second generation which should thereby ensure their eventual substitution. Furthermore, rye telosomes and a wheat-rye chromosome translocation involving 5RL were also observed as possibly useful modifications of the rye chromosomes in this breeding program.

Relative rate of development of aneuploid and euploid microspores in a tertiary trisomic of rye, Secale cereale L.

1985 ◽  
Vol 27 (4) ◽  
pp. 393-398 ◽  
Author(s):  
J. Janse
Keyword(s):  
Mitotic Index ◽  
Secale Cereale ◽  
Time Scale ◽  
Relative Rate ◽  
Pollen Mitosis ◽  
Rate Of Development ◽  
Pollen Mother Cells ◽  
Secale Cereale L ◽  
First Pollen Mitosis ◽  
Mother Cells

Meiotic configurations were studied in pollen mother cells of a tertiary trisomic of rye. Chains of five and chains of three, in alternate orientation, were the most frequent configurations. Assuming loss of univalents in anaphase I or single chromatids in anaphase II, a total of 58.1% of the viable gametes resulting after meiosis were expected to contain the normal haploid complement, whereas 41.9% were expected to have the translocated chromosome in addition. The percentages of uninucleate and binucleate microspores in anthers containing dividing microspores provided a time scale for the development of euploid and aneuploid spores during first pollen mitosis. Microspores containing the extra translocated chromosome tended to divide at a later stage than euploid microspores. The slower development was also illustrated by the course of the mitotic index of both types. It was found that 58.1% of all microspores passing through pollen mitosis contained seven chromosomes and 41.9% contained eight chromosomes, which means that up to the end of first pollen mitosis aneuploid spores were not lost significantly more than euploid spores. It is likely that the delay in development already starts immediately after meiosis.Key words: rye, tertiary trisomic, euploid microspores, aneuploid microspores, rate of development.

Effect of auxins and cytokinins upon the start of meiosis in cultured anthers of rye (Secale cereale L.)

1985 ◽  
Vol 27 (6) ◽  
pp. 759-765 ◽  
Author(s):  
J. Rueda ◽  
A. M. Vázquez
Keyword(s):  
Anther Culture ◽  
Plant Hormones ◽  
Secale Cereale ◽  
Meiotic Division ◽  
Basic Medium ◽  
Differential Capacity ◽  
Pollen Mother Cells ◽  
Secale Cereale L ◽  
Mother Cells

Anthers of rye excised at premeiotic interphase were cultured in vitro on a basic medium and on a series of auxin- and cytokinin-containing media to ascertain the effect of these plant hormones upon the start of meiosis. Only in the hormone-containing media was it possible to find anthers in which pollen mother cells had started the meiotic division. The different hormones and concentrations tested exhibited a differential capacity to induce the start of meiosis, the percentages of anthers with pollen mother cells in meiosis varying from 0% in one medium to more than 60% in two other media. In some media, pollen mother cells were able to complete the whole meiotic division, while in others they were arrested at different stages of meiosis.Key words: Secale cereale, meiosis induction, anther culture, plant hormones.

Refined physical mapping of the Sec-1 locus on the satellite of chromosome 1R of rye (Secale cereale)

Genome ◽  
1995 ◽  
Vol 38 (5) ◽  
pp. 889-893 ◽  
Author(s):  
W. Busch ◽  
R. G. Herrmann ◽  
R. Martin
Keyword(s):  
In Situ Hybridization ◽  
Genetic Mapping ◽  
Fluorescence In Situ Hybridization ◽  
Physical Mapping ◽  
Secale Cereale ◽  
Secondary Constriction ◽  
Heterologous Hybridization ◽  
Secale Cereale L ◽  
Chromosome 1R

The Sec-1 locus (ω-secalin) of rye (Secale cereale L.) was mapped in the satellite of the short arm of chromosome 1R using fluorescence in situ hybridization and a genomic probe called pSec2B. Sec-1 is located in the middle of the satellite at the junction of the proximal euchromatic and the distal heterochromatic regions. Double hybridization experiments using rDNA and pSec2B showed that the NOR spans over the secondary constriction of the short arm of chromosome 1R and that there is a clearly visible gap between the NOR and Sec-1. Heterologous hybridization of pSec2B to barley visualized the B-hordein locus on chromosome 1H.Key words: fluorescence in situ hybridization, physical mapping, genetic mapping, secalin, rye, B-hordein, rDNA.

scholarly journals Changes in poly(a)+ RNA during male meiosis in Lilium

1983 ◽  
Vol 62 (1) ◽  
pp. 177-186
Author(s):  
E.K. Porter ◽  
D. Parry ◽  
H.G. Dickinson
Keyword(s):  
Rna Synthesis ◽  
Liquid Scintillation ◽  
Male Meiosis ◽  
Hybridization Study ◽  
Small Peak ◽  
Plant Life ◽  
Dramatic Decline ◽  
Plant Life Cycle ◽  
Mother Cells

Levels of poly(A)+ RNA have been investigated at each stage of male meiosis in Lilium (var. Firecracker). Two methods were employed in this work: in one extracts from labelled meiocytes were passed through oligo(dT) columns, while in the other the specific probe [3H]poly(U) was hybridized in situ with resin-embedded sections of pollen mother cells. The label contained in the eluate from the oligo(dT) columns was measured by liquid scintillation, and the quantity of [3H]-poly(U) hybridized was determined by statistical analysis of light microscopic autoradiographs. Both techniques revealed a dramatic decline in detectable poly(A)+ RNA during prophase. Lowest levels are reached in the pachytene stage, following which a gradual restoration of this species of RNA takes place in both nucleus and cytoplasm. The data presented here provide no clear indication as to whether this fall in RNA levels is caused by the action of novel enzymes specific to the meiotic prophase, by a cessation of synthesis and the activity of normal turnover processes, or by a combination of the two. Although there is some evidence from the [3H]poly(U) hybridization study that a small peak of poly(A)+ RNA synthesis may take place in leptotene, both methods indicate that there is a very low of poly(A)+ RNA synthesis throughout prophase. The presence of poly(A)+ RNA was not detected in either the accessory nucleoli or the cytoplasmic nucleoloids that characterize the nucleus and cytoplasm of these cells. These events are considered in terms of the juncture at which they occur in the plant life-cycle.

Identification of Bilby, a diverged centromeric Ty1-copia retrotransposon family from cereal rye (Secale cereale L.)

Genome ◽  
2001 ◽  
Vol 44 (2) ◽  
pp. 266-274 ◽  
Author(s):  
Michael G Francki
Keyword(s):  
Sequence Similarity ◽  
Repetitive Sequences ◽  
Normal Function ◽  
Cereal Rye ◽  
Dna Database ◽  
Centromeric Sequence ◽  
Retrotransposon Family ◽  
Secale Cereale L ◽  
Copia Retrotransposon

A diminutive rye chromosome (midget) in wheat was used as a model system to isolate a highly reiterated centromeric sequence from a rye chromosome. Fluorescence in situ hybridization (FISH) shows this sequence localized within all rye centromeres and no signal was detected on wheat chromosomes. DNA sequencing of the repetitive element has revealed the presence of some catalytic domains and signature motifs typical of retrotransposon genes and has been called the Bilby family, representing a diverged family of retrotransposon-like elements. Extensive DNA database searching revealed some sequence similarity to centromeric retrotransposons from wheat, barley, and centromeric repetitive sequences from rice. Very low levels of signal were observed when Bilby was used as a probe against barley, and no signal was detected with rice DNA during Southern hybridization. The abundance of Bilby in rye indicates that this family may have diverged from other distantly related centromeric retrotransposons or incorporated in the centromere but rapidly evolved in rye during speciation. The isolation of a rye retrotransposon also allowed the analysis of centromeric breakpoints in wheat-rye translocation lines. A quantitative analysis shows that the breakpoint in 1DS.1RL and 1DL.1RS and recombinant lines containing proximal rye chromatin have a portion of the rye centromere that may contribute to the normal function of the centromeric region.Key words: centromere, retrotransposon, rye, midget chromosome, cereals.

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