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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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Quantification of Mcd1p foci on pachytene chromosomes in tid1Δ and wild-type. Mcd1p is visualized with anti-Mcd1p antibodies. Pachytene cells are identified as cells with clearly visible bivalents (visualized using DAPI) containing duplicated SPBs (visualized using antitubulin antibodies). Differences between tid1Δ and wild-type are statistically significant (P < 0.05; X2 test).
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fig8: Quantification of Mcd1p foci on pachytene chromosomes in tid1Δ and wild-type. Mcd1p is visualized with anti-Mcd1p antibodies. Pachytene cells are identified as cells with clearly visible bivalents (visualized using DAPI) containing duplicated SPBs (visualized using antitubulin antibodies). Differences between tid1Δ and wild-type are statistically significant (P < 0.05; X2 test).

Mentions: Early suppression of tid1Δ anaphase block by mcd1-1 in a spo11Δ spo13Δ background suggests that the misregulation of Mcd1p in the absence of Tid1p occurs before or during prophase. To confirm that tid1Δ has an effect on Mcd1p during prophase, Mcd1p was visualized by immunolabeling in spread nuclei of pachytene tid1Δ and wild-type cells, which were identified by the appearance of well-condensed chromosome bivalents. Mcd1p appears as spots on chromatin in spread preparations of pachytene cells (Klein et al., 1999; unpublished data). The number of Mcd1p spots on pachytene chromosomes in tid1Δ is significantly increased compared with wild type (Fig. 8), suggesting that the functional interaction between Mcd1p and Tid1p begins before or during pachytene. Thus, the misregulation of Mcd1p and, perhaps as a consequence, of Rec8p in or before prophase may lead to sister chromatid connections that persist through both anaphases and prevent chromosome segregation in both divisions of tid1Δ.


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)

Quantification of Mcd1p foci on pachytene chromosomes in tid1Δ and wild-type. Mcd1p is visualized with anti-Mcd1p antibodies. Pachytene cells are identified as cells with clearly visible bivalents (visualized using DAPI) containing duplicated SPBs (visualized using antitubulin antibodies). Differences between tid1Δ and wild-type are statistically significant (P < 0.05; X2 test).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2171180&req=5

fig8: Quantification of Mcd1p foci on pachytene chromosomes in tid1Δ and wild-type. Mcd1p is visualized with anti-Mcd1p antibodies. Pachytene cells are identified as cells with clearly visible bivalents (visualized using DAPI) containing duplicated SPBs (visualized using antitubulin antibodies). Differences between tid1Δ and wild-type are statistically significant (P < 0.05; X2 test).
Mentions: Early suppression of tid1Δ anaphase block by mcd1-1 in a spo11Δ spo13Δ background suggests that the misregulation of Mcd1p in the absence of Tid1p occurs before or during prophase. To confirm that tid1Δ has an effect on Mcd1p during prophase, Mcd1p was visualized by immunolabeling in spread nuclei of pachytene tid1Δ and wild-type cells, which were identified by the appearance of well-condensed chromosome bivalents. Mcd1p appears as spots on chromatin in spread preparations of pachytene cells (Klein et al., 1999; unpublished data). The number of Mcd1p spots on pachytene chromosomes in tid1Δ is significantly increased compared with wild type (Fig. 8), suggesting that the functional interaction between Mcd1p and Tid1p begins before or during pachytene. Thus, the misregulation of Mcd1p and, perhaps as a consequence, of Rec8p in or before prophase may lead to sister chromatid connections that persist through both anaphases and prevent chromosome segregation in both divisions of tid1Δ.

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