The role of the ameiotic1 gene in the initiation of meiosis and in subsequent meiotic events in maize.
The role of the ameiotic1 gene in the initiation of meiosis and in subsequent meiotic events in maize.
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发表时间：
1993-12
期刊：
影响因子：
3.3
通讯作者：
I. Golubovskaya;Z. K. Grebennikova;N. Avalkina;W. Sheridan
中科院分区：
文献类型：
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作者：
I. Golubovskaya;Z. K. Grebennikova;N. Avalkina;W. Sheridan
了解减数分裂的启动及其与其他关键细胞遗传学过程的关系是研究高等植物减数分裂遗传控制的主要目标。我们的遗传和结构分析的ameiotic 1基因（am 1和am 1-praI）的两个突变等位基因表明，该位点在玉米减数分裂的启动中起着至关重要的作用。ameiotic 1基因的产物比玉米中任何其他已知基因影响减数分裂序列中的较早阶段，并且对于细胞减数分裂的不可逆承诺和标记从减数分裂前间期进入前期I（包括染色体联会）的关键事件是重要的。看来，ameiotic 1基因在减数分裂中的功能期至少包括从减数分裂前间期的某个点到减数分裂的偶线期早期的间隔。为了研究减数分裂过程中基因间的相互作用，构建了几个双减数分裂突变体。在这些双突变体中，（i）无减数分裂1突变等位基因与减数分裂突变（afd 1）结合在一起，后者负责减数分裂中着丝粒的固定;控制同源染色体分离的三个减数分裂基因的突变等位基因（DV 1，MS 43和MS 28），其损害微管组织中心的组织，纺锤体纤维装置的定向，和第一次减数分裂后纺锤丝的解聚;（ii）afd 1突变与两个突变相结合，（iii）ms 43突变与as 1、ms 28和dv 1突变组合;和（iv）MS 28突变与DV 1突变和MS 4（多有丝分裂1）突变组合。对双突变体中基因相互作用的分析使我们得出结论，ameiotic 1基因在afd 1、dv 1、ms 43和ms 28基因上是上位性的，但这种关系的意义需要进一步分析。afd基因似乎在整个第一次减数分裂过程中从减数分裂前间期开始发挥作用，但它的功能很可能是在ameiotic 1基因表达开始后才开始的。afd 1基因在两个突触突变dsy 1和as 1以及dv 1突变上是上位性的。从活跃的Robertson突变体中分离的新的无减数分裂 *-485和细线期阻滞 *-487突变参与控制减数分裂的起始。
Understanding the initiation of meiosis and the relationship of this event with other key cytogenetic processes are major goals in studying the genetic control of meiosis in higher plants. Our genetic and structural analysis of two mutant alleles of the ameiotic1 gene (am1 and am1-praI) suggest that this locus plays an essential role in the initiation of meiosis in maize. The product of the ameiotic1 gene affects an earlier stage in the meiotic sequence than any other known gene in maize and is important for the irreversible commitment of cells to meiosis and for crucial events marking the passage from premeiotic interphase into prophase I including chromosome synapsis. It appears that the period of ameiotic1 gene function in meiosis at a minimum covers the interval from some point during premeiotic interphase until the early zygotene stage of meiosis. To study the interaction of genes in the progression of meiosis, several double meiotic mutants were constructed. In these double mutants (i) the ameiotic1 mutant allele was brought together with the meiotic mutation (afd1) responsible for the fixation of centromeres in meiosis; and with the mutant alleles of the three meiotic genes that control homologous chromosome segregation (dv1, ms43 and ms28), which impair microtubule organizing center organization, the orientation of the spindle fiber apparatus, and the depolymerization of spindle filaments after the first meiotic division, respectively; (ii) the afd1 mutation was combined with two mutations (dsy1 and as1) affecting homologous pairing; (iii) the ms43 mutation was combined with the as1, the ms28 and the dv1 mutations; and (iv) the ms28 mutation was combined with the dv1 mutation and the ms4 (polymitotic1) mutations. An analysis of gene interaction in the double mutants led us to conclude that the ameiotic1 gene is epistatic over the afd1, the dv1, the ms43 and the ms28 genes but the significance of this relationship requires further analysis. The afd gene appears to function from premeiotic interphase throughout the first meiotic division, but it is likely that its function begins after the start of the ameiotic1 gene expression. The afd1 gene is epistatic over the two synaptic mutations dsy1 and as1 and also over the dv1 mutation. The new ameiotic*-485 and leptotene arrest*-487 mutations isolated from an active Robertson's Mutator stocks take part in the control of the initiation of meiosis.