The cyclin-A CYCA1;2/TAM is required for the meiosis I to meiosis II transition and cooperates with OSD1 for the prophase to first meiotic division transition.
The cyclin-A CYCA1;2/TAM is required for the meiosis I to meiosis II transition and cooperates with OSD1 for the prophase to first meiotic division transition.
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DOI：
10.1371/journal.pgen.1000989
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发表时间：
2010-06-17
期刊：
影响因子：
4.5
通讯作者：
Mercier R
中科院分区：
文献类型：
--
作者：
d'Erfurth I;Cromer L;Jolivet S;Girard C;Horlow C;Sun Y;To JP;Berchowitz LE;Copenhaver GP;Mercier R
减数分裂使染色体数量减半，因为它的两次分裂遵循单轮 DNA 复制。这个过程涉及两次细胞转变，从前期到第一次减数分裂（减数分裂I）的转变以及独特的减数分裂I到减数分裂II的转变。我们在此表明 A 型细胞周期蛋白 CYCA1;2/TAM 在拟南芥的两个转变中都发挥着重要作用。一系列tam突变体未能进入减数分裂II，从而产生二倍体孢子和功能性二倍体配子。这些二倍体配子具有通过单次减数分裂 I 分裂产生的重组基因型。此外，通过将 tam-2 突变与 AtSpo11-1 和 Atrec8 相结合，我们获得了通过有丝分裂样分裂产生二倍体配子的植物，其遗传与其亲本相同。因此，tam 等位基因表现出与之前描述的 osd1 突变体非常相似的表型。 tam 和 osd1 突变的结合会导致雄性减数分裂期间减数分裂 I 过渡的前期失败以及四倍体孢子和配子的产生。这表明 TAM 和 OSD1 参与了两个减数分裂转变的控制。在有性生物的生命周期中，特殊的细胞分裂（减数分裂）将染色体数量从两组（2n，二倍体）减少到一组（n，单倍体），而受精则恢复原始染色体数量。减数分裂会减少倍性，因为它由一次 DNA 复制后的两次分裂组成。在这项研究中，我们鉴定了控制模式植物拟南芥进入第一次和第二次减数分裂的基因。缺乏 CYCA1;2 基因的植物在减数分裂过程中执行一次分裂，产生功能性二倍体配子和下一代多倍体植物。通过将该突变与影响关键减数分裂过程的其他两个突变结合起来，我们培育出了通过类似有丝分裂的分裂产生二倍体配子的植物，这些配子在遗传上与其亲本相同。此外，缺乏 CYCA1;2 和另一个先前描述的基因 (OSD1) 的植物在雄性减数分裂期间不会发生分裂，产生四倍体花粉粒。
Meiosis halves the chromosome number because its two divisions follow a single round of DNA replication. This process involves two cell transitions, the transition from prophase to the first meiotic division (meiosis I) and the unique meiosis I to meiosis II transition. We show here that the A-type cyclin CYCA1;2/TAM plays a major role in both transitions in Arabidopsis. A series of tam mutants failed to enter meiosis II and thus produced diploid spores and functional diploid gametes. These diploid gametes had a recombined genotype produced through the single meiosis I division. In addition, by combining the tam-2 mutation with AtSpo11-1 and Atrec8, we obtained plants producing diploid gametes through a mitotic-like division that were genetically identical to their parents. Thus tam alleles displayed phenotypes very similar to that of the previously described osd1 mutant. Combining tam and osd1 mutations leads to a failure in the prophase to meiosis I transition during male meiosis and to the production of tetraploid spores and gametes. This suggests that TAM and OSD1 are involved in the control of both meiotic transitions. In the life cycle of sexual organisms, a specialized cell division—meiosis—reduces the number of chromosomes from two sets (2n, diploid) to one set (n, haploid), while fertilization restores the original chromosome number. Meiosis reduces ploidy because it consists of two divisions following a single DNA replication. In this study, we identified genes that control the entry into the first and the second meiotic division in the model plant Arabidopsis thaliana. Plants lacking the CYCA1;2 gene execute a single division during meiosis producing functional diploid gametes and polyploid plants in the next generation. By combining this mutation with two others that affect key meiotic processes, we generated plants that produce diploid gametes through a mitotic-like division that are genetically identical to their parents. Furthermore, plants lacking CYCA1;2 and another previously described gene (OSD1) undergo no divisions during male meiosis, producing tetraploid pollen grains.
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ATMUS81在A. thaliana中对干扰不敏感的交叉中的作用。
影响因子：
4.5
作者：
Berchowitz, Luke E.;Francis, Kirk E.;Bey, Alexandra L.;Copenhaver, Gregory P.
通讯作者：
Copenhaver, Gregory P.
影响因子：
56.9
作者：
Alonso, JM;Stepanova, AN;Ecker, JR
通讯作者：
Ecker, JR
影响因子：
14.8
作者：
Berchowitz, Luke E.;Copenhaver, Gregory P.
通讯作者：
Copenhaver, Gregory P.
DOI：
10.1073/pnas.0608936104
发表时间：
2007-03-06
影响因子：
11.1
作者：
Francis, Kirk E.;Lam, Sandy Y.;Copenhaver, Gregory P.
通讯作者：
Copenhaver, Gregory P.
影响因子：
3.3
作者：
Kiburz, Brendan M.;Amon, Angelika;Marston, Adele L.
通讯作者：
Marston, Adele L.