鸭跖草科酸模属 Y 染色体的功能。

Function ofY chromosomes inRumex thyrsijlorus.

Department of Genetics, Polish Academy of Sciences, Warsaw, Poland.

Theor Appl Genet. 1970 Mar;40(3):124-9. doi: 10.1007/BF00997005.

Abstract

Numerous polyploid and diploid plants ofR. thyrsiflorus with various numbers ofX andY chromoso mes were obtained. Analysis of these plants confirmed earlier conclusions (Żuk, 1963) thatY chromosomes carry no sex-determining genes. 2. Investigation of pollen fertility of male plants withoutY chromosomes, and with one or moreY chromosomes, seems to indicate that in theY chromosomes ofR. thyrsiflorus are located some factors reponsible for the fertility of male plants. This result is supported by cytological data (Żuk, 1969) indicating thatY chromosomes ofR. thyrsiflorus are active in premeiotic stages of microsporogenesis. Meiosis in plants withoutY chromosomes and with oneY chromosome was also studied. In all cases conjugation of chromosomes and meiotic divisions in PMC were normal. These data suggest that there are no genes located inY chromosomes responsible for synapsis or the course of meiotic division in PMC ofR. thyrsiflorus. 3. In a natural population ofR. thyrsiflorus the male individuals are less numerous than the female ones. This is due to nonrandom fertilization. The gametesYY + 6A = 8 fertilize less frequently than do gametesX + 6 A = 7. In crosses involving a male plant with chromosome constitutionXYYYY + 12A = 17, which produces more uniform gametes as regardsY chromosomes, there were more male individuals than normally. This is interpreted as evidence that the preponderance of females inR. thyrsiflorus is connected withY chromosomes.

摘要

获得了大量具有不同 X 和 Y 染色体数目的多倍体和二倍体紫堇属（R.thyrsiflorus）植物。对这些植物的分析证实了早期的结论（Żuk，1963），即 Y 染色体不携带性别决定基因。
对没有 Y 染色体和有一个或多个 Y 染色体的雄性植物的花粉育性进行调查，似乎表明 Y 染色体上携带了一些与雄性植物育性有关的因子。这一结果得到细胞学数据的支持（Żuk，1969），表明紫堇属 Y 染色体在花粉母细胞减数分裂前期是活跃的。也研究了没有 Y 染色体和有一个 Y 染色体的植物的减数分裂。在所有情况下，染色体的联会和 PMC 中的减数分裂都是正常的。这些数据表明，在 Y 染色体上不存在负责 PMC 中联会或减数分裂过程的基因。
在紫堇属的自然种群中，雄性个体比雌性个体数量少。这是由于非随机受精。YY + 6A = 8 配子比 X + 6A = 7 配子受精频率低。在涉及染色体组成为 XYYYY + 12A = 17 的雄性植物的杂交中，产生的 Y 染色体更均匀的配子受精频率更高，因此雄性个体比正常情况下更多。这可以解释为，紫堇属中雌性占优势与 Y 染色体有关。