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Recombination protein Tid1p controls resolution of cohesin-dependent linkages in meiosis in Saccharomyces cerevisiae.

Kateneva AV, Konovchenko AA, Guacci V, Dresser ME - J. Cell Biol. (2005)

Bottom Line: Genetic results indicate that the primary defect in these cells is a failure to resolve Mcd1p-mediated connections.Tid1p interacts with recombination enzymes Dmc1p and Rad51p and has an established role in recombination repair.We propose that Tid1p remodels Mcd1p-mediated cohesion early in meiotic prophase to facilitate interhomologue recombination and the subsequent segregation of homologous chromosomes.

View Article: PubMed Central - PubMed

Affiliation: Program in Molecular, Cell, and Developmental Biology, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104.

ABSTRACT
Sister chromatid cohesion and interhomologue recombination are coordinated to promote the segregation of homologous chromosomes instead of sister chromatids at the first meiotic division. During meiotic prophase in Saccharomyces cerevisiae, the meiosis-specific cohesin Rec8p localizes along chromosome axes and mediates most of the cohesion. The mitotic cohesin Mcd1p/Scc1p localizes to discrete spots along chromosome arms, and its function is not clear. In cells lacking Tid1p, which is a member of the SWI2/SNF2 family of helicase-like proteins that are involved in chromatin remodeling, Mcd1p and Rec8p persist abnormally through both meiotic divisions, and chromosome segregation fails in the majority of cells. Genetic results indicate that the primary defect in these cells is a failure to resolve Mcd1p-mediated connections. Tid1p interacts with recombination enzymes Dmc1p and Rad51p and has an established role in recombination repair. We propose that Tid1p remodels Mcd1p-mediated cohesion early in meiotic prophase to facilitate interhomologue recombination and the subsequent segregation of homologous chromosomes.

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Segregation defects of tid1Δ in the spo11Δ spo13Δ background. (A) Segregation of sister chromatids in spo11Δ spo13Δ. Grey lines connected by black dots represent sister chromatids that are connected by cohesin complexes. Thickenings represent centromeres. Arrows represent the pulling forces of the spindle. (B) Kinetics of exit from the single meiotic division as marked by the appearance of binucleates. (C) Percentage of dumbbells. (D) Percentage of dumbbells and binucleates. The value at each point in graph B is derived by adding the values from the same time point in graphs C and D. 200 or more cells were scored at each time point. (E) Schematic representation of possible outcomes of segregation of sister chromatids labeled with telomere and centromere GFP spots in spo11Δ spo13Δ tid1Δ. White dots represent GFP spots. Black rings around sister chromatid represent connections persisting in tid1Δ. Only the labeled chromosome is shown. (F) Comparison of the segregation of chromosome IV sister chromatids in total populations of spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ. Differences between spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ are statistically significant (P < 0.05; X2 test). (G) Segregation of chromosome IV sister chromatids labeled by centromere and telomere GFP spots in postprophase cells only. Data in F and G are results from the same experiment. Above the pictures are the percentages of each class of cells in the total population. Only classes of cells representing >3% of the total population are shown for spo11Δ spo13Δ tid1Δ, and only those same classes of cells are shown for spo11Δ spo13Δ as controls. Bars, 2 μm.
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fig3: Segregation defects of tid1Δ in the spo11Δ spo13Δ background. (A) Segregation of sister chromatids in spo11Δ spo13Δ. Grey lines connected by black dots represent sister chromatids that are connected by cohesin complexes. Thickenings represent centromeres. Arrows represent the pulling forces of the spindle. (B) Kinetics of exit from the single meiotic division as marked by the appearance of binucleates. (C) Percentage of dumbbells. (D) Percentage of dumbbells and binucleates. The value at each point in graph B is derived by adding the values from the same time point in graphs C and D. 200 or more cells were scored at each time point. (E) Schematic representation of possible outcomes of segregation of sister chromatids labeled with telomere and centromere GFP spots in spo11Δ spo13Δ tid1Δ. White dots represent GFP spots. Black rings around sister chromatid represent connections persisting in tid1Δ. Only the labeled chromosome is shown. (F) Comparison of the segregation of chromosome IV sister chromatids in total populations of spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ. Differences between spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ are statistically significant (P < 0.05; X2 test). (G) Segregation of chromosome IV sister chromatids labeled by centromere and telomere GFP spots in postprophase cells only. Data in F and G are results from the same experiment. Above the pictures are the percentages of each class of cells in the total population. Only classes of cells representing >3% of the total population are shown for spo11Δ spo13Δ tid1Δ, and only those same classes of cells are shown for spo11Δ spo13Δ as controls. Bars, 2 μm.

Mentions: The effect of TID1 deletion on the ability of cells to separate sister chromatids was tested in a background where sister chromatids segregate instead of homologues. The introduction of spo13Δ in the spo11Δ background, where meiotic recombination is eliminated, leads to biorientation of sister kinetochores and subsequent segregation of sister chromatids in the single meiotic division (Fig. 3 A; Klapholz et al., 1985; Shonn et al., 2002). In spo11Δ spo13Δ tid1Δ, 23% of cells complete the separation of chromatin into two masses (binucleates) compared with 66% of cells in spo11Δ spo13Δ (Fig. 3 B). Thus, even in the absence of interhomologue recombination, the deletion of TID1 prevents some spo11Δ spo13Δ cells from successfully finishing the division, presumably because of the failure to segregate sister chromatids in the absence of Tid1p. Consistently, one reason for the reduction in the percentage of binucleates is the accumulation of dumbbells (Fig. 3 C), which begin degrading at ∼10 h into sporulation (unpublished data). Another reason is an accumulation of cells with a single unstretched mass of chromatin (mononucleates) and a short spindle. In spo11Δ spo13Δ tid1Δ, only 40% of cells progress past mononucleate stage (Fig. 3 D) compared with 70% in spo11Δ tid1Δ (Fig. 2 B), which is higher than the 15–25% in tid1Δ but lower than the 66% in spo11Δ spo13Δ (Fig. 3 B). Tagging of spindle tubulin with GFP reveals that the mononucleate cells consist of two classes: cells with a single spindle pole body (SPB) and cells with a short spindle. To determine what percentage of the population is represented by each class, we scored 50 spo11Δ spo13Δ mononucleate cells (29% of the total population is mononucleate at 8 h) and 68 spo11Δ spo13Δ tid1Δ mononucleate cells (53% of the total population is mononucleate at 8 h). The fraction of cells with a single SPB is similar in spo11Δ spo13Δ and spo11Δ spo13Δ tid1Δ (14% of each total population). However, the fraction of cells with a short spindle is lower in spo11Δ spo13Δ than in spo11Δ spo13Δ tid1Δ: 15 versus 39% of the total population, respectively. In addition, the fraction of cells with a short spindle subsequently decreases in spo11Δ spo13Δ, whereas it persists essentially unchanged in spo11Δ spo13Δ tid1Δ (unpublished data). Thus, the failure of spo11Δ spo13Δ tid1Δ cells to divide their chromatin into two masses can be attributed to a block with two phenotypes: dumbbells and mononucleate cells with a short spindle. The tid1 K351R allele, which is designed to eliminate ATP hydrolysis (Petukhova et al., 2000), causes a similar block in the spo11Δ spo13Δ background (unpublished data). A similar phenotype has been reported in other mutants where sister chromatids fail to segregate, leading to a block with a metaphase-length spindle (Toth et al., 2000; Clyne et al., 2003; Lee and Amon, 2003; Rabitsch et al., 2003).


Recombination protein Tid1p controls resolution of cohesin-dependent linkages in meiosis in Saccharomyces cerevisiae.

Kateneva AV, Konovchenko AA, Guacci V, Dresser ME - J. Cell Biol. (2005)

Segregation defects of tid1Δ in the spo11Δ spo13Δ background. (A) Segregation of sister chromatids in spo11Δ spo13Δ. Grey lines connected by black dots represent sister chromatids that are connected by cohesin complexes. Thickenings represent centromeres. Arrows represent the pulling forces of the spindle. (B) Kinetics of exit from the single meiotic division as marked by the appearance of binucleates. (C) Percentage of dumbbells. (D) Percentage of dumbbells and binucleates. The value at each point in graph B is derived by adding the values from the same time point in graphs C and D. 200 or more cells were scored at each time point. (E) Schematic representation of possible outcomes of segregation of sister chromatids labeled with telomere and centromere GFP spots in spo11Δ spo13Δ tid1Δ. White dots represent GFP spots. Black rings around sister chromatid represent connections persisting in tid1Δ. Only the labeled chromosome is shown. (F) Comparison of the segregation of chromosome IV sister chromatids in total populations of spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ. Differences between spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ are statistically significant (P < 0.05; X2 test). (G) Segregation of chromosome IV sister chromatids labeled by centromere and telomere GFP spots in postprophase cells only. Data in F and G are results from the same experiment. Above the pictures are the percentages of each class of cells in the total population. Only classes of cells representing >3% of the total population are shown for spo11Δ spo13Δ tid1Δ, and only those same classes of cells are shown for spo11Δ spo13Δ as controls. Bars, 2 μm.
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Related In: Results  -  Collection

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fig3: Segregation defects of tid1Δ in the spo11Δ spo13Δ background. (A) Segregation of sister chromatids in spo11Δ spo13Δ. Grey lines connected by black dots represent sister chromatids that are connected by cohesin complexes. Thickenings represent centromeres. Arrows represent the pulling forces of the spindle. (B) Kinetics of exit from the single meiotic division as marked by the appearance of binucleates. (C) Percentage of dumbbells. (D) Percentage of dumbbells and binucleates. The value at each point in graph B is derived by adding the values from the same time point in graphs C and D. 200 or more cells were scored at each time point. (E) Schematic representation of possible outcomes of segregation of sister chromatids labeled with telomere and centromere GFP spots in spo11Δ spo13Δ tid1Δ. White dots represent GFP spots. Black rings around sister chromatid represent connections persisting in tid1Δ. Only the labeled chromosome is shown. (F) Comparison of the segregation of chromosome IV sister chromatids in total populations of spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ. Differences between spo11Δ spo13Δ tid1Δ and spo11Δ spo13Δ are statistically significant (P < 0.05; X2 test). (G) Segregation of chromosome IV sister chromatids labeled by centromere and telomere GFP spots in postprophase cells only. Data in F and G are results from the same experiment. Above the pictures are the percentages of each class of cells in the total population. Only classes of cells representing >3% of the total population are shown for spo11Δ spo13Δ tid1Δ, and only those same classes of cells are shown for spo11Δ spo13Δ as controls. Bars, 2 μm.
Mentions: The effect of TID1 deletion on the ability of cells to separate sister chromatids was tested in a background where sister chromatids segregate instead of homologues. The introduction of spo13Δ in the spo11Δ background, where meiotic recombination is eliminated, leads to biorientation of sister kinetochores and subsequent segregation of sister chromatids in the single meiotic division (Fig. 3 A; Klapholz et al., 1985; Shonn et al., 2002). In spo11Δ spo13Δ tid1Δ, 23% of cells complete the separation of chromatin into two masses (binucleates) compared with 66% of cells in spo11Δ spo13Δ (Fig. 3 B). Thus, even in the absence of interhomologue recombination, the deletion of TID1 prevents some spo11Δ spo13Δ cells from successfully finishing the division, presumably because of the failure to segregate sister chromatids in the absence of Tid1p. Consistently, one reason for the reduction in the percentage of binucleates is the accumulation of dumbbells (Fig. 3 C), which begin degrading at ∼10 h into sporulation (unpublished data). Another reason is an accumulation of cells with a single unstretched mass of chromatin (mononucleates) and a short spindle. In spo11Δ spo13Δ tid1Δ, only 40% of cells progress past mononucleate stage (Fig. 3 D) compared with 70% in spo11Δ tid1Δ (Fig. 2 B), which is higher than the 15–25% in tid1Δ but lower than the 66% in spo11Δ spo13Δ (Fig. 3 B). Tagging of spindle tubulin with GFP reveals that the mononucleate cells consist of two classes: cells with a single spindle pole body (SPB) and cells with a short spindle. To determine what percentage of the population is represented by each class, we scored 50 spo11Δ spo13Δ mononucleate cells (29% of the total population is mononucleate at 8 h) and 68 spo11Δ spo13Δ tid1Δ mononucleate cells (53% of the total population is mononucleate at 8 h). The fraction of cells with a single SPB is similar in spo11Δ spo13Δ and spo11Δ spo13Δ tid1Δ (14% of each total population). However, the fraction of cells with a short spindle is lower in spo11Δ spo13Δ than in spo11Δ spo13Δ tid1Δ: 15 versus 39% of the total population, respectively. In addition, the fraction of cells with a short spindle subsequently decreases in spo11Δ spo13Δ, whereas it persists essentially unchanged in spo11Δ spo13Δ tid1Δ (unpublished data). Thus, the failure of spo11Δ spo13Δ tid1Δ cells to divide their chromatin into two masses can be attributed to a block with two phenotypes: dumbbells and mononucleate cells with a short spindle. The tid1 K351R allele, which is designed to eliminate ATP hydrolysis (Petukhova et al., 2000), causes a similar block in the spo11Δ spo13Δ background (unpublished data). A similar phenotype has been reported in other mutants where sister chromatids fail to segregate, leading to a block with a metaphase-length spindle (Toth et al., 2000; Clyne et al., 2003; Lee and Amon, 2003; Rabitsch et al., 2003).

Bottom Line: Genetic results indicate that the primary defect in these cells is a failure to resolve Mcd1p-mediated connections.Tid1p interacts with recombination enzymes Dmc1p and Rad51p and has an established role in recombination repair.We propose that Tid1p remodels Mcd1p-mediated cohesion early in meiotic prophase to facilitate interhomologue recombination and the subsequent segregation of homologous chromosomes.

View Article: PubMed Central - PubMed

Affiliation: Program in Molecular, Cell, and Developmental Biology, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104.

ABSTRACT
Sister chromatid cohesion and interhomologue recombination are coordinated to promote the segregation of homologous chromosomes instead of sister chromatids at the first meiotic division. During meiotic prophase in Saccharomyces cerevisiae, the meiosis-specific cohesin Rec8p localizes along chromosome axes and mediates most of the cohesion. The mitotic cohesin Mcd1p/Scc1p localizes to discrete spots along chromosome arms, and its function is not clear. In cells lacking Tid1p, which is a member of the SWI2/SNF2 family of helicase-like proteins that are involved in chromatin remodeling, Mcd1p and Rec8p persist abnormally through both meiotic divisions, and chromosome segregation fails in the majority of cells. Genetic results indicate that the primary defect in these cells is a failure to resolve Mcd1p-mediated connections. Tid1p interacts with recombination enzymes Dmc1p and Rad51p and has an established role in recombination repair. We propose that Tid1p remodels Mcd1p-mediated cohesion early in meiotic prophase to facilitate interhomologue recombination and the subsequent segregation of homologous chromosomes.

Show MeSH
Related in: MedlinePlus