Khovanova E M
Genetika. 1977;13(12):2173-80.
Effects of yeast, propionic acid and ethanol on the activity of H-factor, which sharply increases the frequency of somatic recombination in X-chromosomes of dorsal prothoracal disc cells in Drosophila simulans are studied. The frequency of yellow and singed mosaic spots in heterozygous yw ++/++sn1vHD. melanogaster females, inherited H-factor from the father (the stock sn1v) is estimated. The results of the varience analysis have shown that yeast and propionic acid regulate the activity of H-factor in cells of dorsal prothoracal disc, the interaction of yeast and propionic acid being also observed. Yeasts (or some unknown product of their metabolism) are the activator of H-factor; thus, when larvae eat much yeast, the frequency of yellow and singed mosaic spots in humeral region becomes high. A decrease of mosaic spot frequency under the increase of propionic acid content in nutrition medium is a result of the inhibitory effect of propionic acid on the yeast growth, but not of the direct repression of H-factor activity. So, propionic acid may be considered as a regulator of the second order. Ethanol does not activate H-factor. Changes in the content of yeast and propionic acid in nutrition medium do not affect the frequency of yellow and singed mosaic spots in other regions of D. simulans body, except humeral.
研究了酵母、丙酸和乙醇对H因子活性的影响，H因子能显著提高拟果蝇背前胸盘细胞X染色体体细胞重组的频率。估计了杂合子yw ++/++sn1v黑腹果蝇雌性中黄色和焦刚毛镶嵌斑的频率，这些雌性从父亲（品系sn1v）那里继承了H因子。方差分析结果表明，酵母和丙酸调节背前胸盘细胞中H因子的活性，同时也观察到酵母和丙酸之间的相互作用。酵母（或其代谢产生的某些未知产物）是H因子的激活剂；因此，当幼虫摄入大量酵母时，肩部区域黄色和焦刚毛镶嵌斑的频率会升高。营养培养基中丙酸含量增加时镶嵌斑频率降低，是丙酸对酵母生长的抑制作用导致的，而非对H因子活性的直接抑制。所以，丙酸可被视为二级调节因子。乙醇不会激活H因子。营养培养基中酵母和丙酸含量的变化不会影响拟果蝇身体除肩部以外其他区域黄色和焦刚毛镶嵌斑的频率。
