Summary
Mitotic recombination has been induced with X-rays in w/w co-marked X-chromosomes of Drosophila melanogaster second instar larvae and assayed later as w;w co-twin mosaic spots in the adult eyes. According to estimates at least 95% of the registered twin spots are due to mitotic recombination. The frequency with which mitotic recombination leads to twin spots can not be given in figures. The dependence of twin spot frequency on dose, dose-rate and spectrum was registered. The spectra of the four filter-voltagecombinations used (45 kV, 0.55 mm Al; 55 kV, 0.78 mm Al; 85 kV, 1.25 mm Al; 100 kV, 1.7 mm Al) were measured by means of a solid state counter. The dose was measured with a Simplex dosimeter.
The results were:
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a)
For 100 kV the dependence of twin spot frequency on the dose has been investigated by two methods: The dose was varied (1) by using different radiation times at a constant dose-rate and (2) by using different dose-rates for a constant radiation time. Both dose effect curves (DEC) show a peculiar hump and subsequently a renewed rise of the curve. The DEC according to (1) lies significantly below the curve according to (2) (Fig. 8).
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b)
The course of the time-dependence curve at 100 kV (Fig. 7) shows that a DEC, which is to have the dose as the only parameter, has to be registered at irradiation times of 30 sec or less.
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c)
The DEC's at 45 and 55 kV (Fig. 9) are identical; they differ considerably in form and altitude from those at 100 kV. The DEC at 85 kV lies between the two with respect to both, form and altitude.
The results given under a) and b) led to the conclusion that an irradiation with 100 kV triggers two reactions, which lead to twin spots in the eyes. There is no such indication for irradiation with 55 kV. A hint as to the nature of these two reactions and a possibility of an explanation for the different effects of 55 kV and 100 kV irradiation is seen in the different qualities of the two spectra.
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Literatur
Abbadessa, R., Burdick, A. B.: The effect of X-irradiation on somatic crossing-over in Drosophila melanogaster. Genetics 48, 1345–1356 (1963).
Becker, H. J.: Über Röntgenmosaikflecken und Defektmutationen am Auge von Drosophila und die Entwicklungsphysiologie des Auges. Z. indukt. Abstamm.-u. Vererb.-L. 88, 333–373 (1957).
—: The influence of heterochromatin, inversion-heterozygosity and somatic pairing on X-ray induced mitotic recombination in Drosophila melanogaster. Molec. gen. Genet. 105, 203–218 (1969).
Drexler, G., Perzl, F.: Methoden zur Spektrometrie niederenergetischer Bremsstrahlung. Premier congres europeen de radioprotection, Menton 9–11 octobre 1968.
Evans, H. J.: Chromosome aberrations induced by ionizing radiation. Int. Rev. Cytol. 13, 221 (1962).
Haendle, J.: Abhängigkeit des strahleninduzierten somatischen Faktorenaustausches von der Strahlenart, der Dosis und der Dosisrate. Phys. Diplomarbeit, München 1967.
Hug, O., Kellerer, A. M.: Stochastik der Strahlenwirkung. Berlin-Heidelberg-New York: Springer 1966.
Jaeger, R., Kolb, W.: Über Beziehungen zwischen der spektralen Verteilung der Impulsrate, Intensität und Dosisleistung einer Röntgenstrahlung. Strahlentherapie 104, 29–35 (1957).
Koyenuma, N.: Beiträge zur Theorie der biologischen Strahlenwirkung. Z. Physik 120, 185 (1943).
Lefèvre, G. J.: The relative effectiveness of fast neutrons and γ-rays in producing somatic crossing over in Drosophila (Abstr.). Rec. Gen. Soc. Amer. 16, 40 (1947).
—: X-ray induced genetic effects in germinal and somatic tissue of Drosophila melanogaster. Amer. Naturalist 84, 341–365 (1950).
Ludwig, W.: Faktorenkopplung und Faktorenaustausch. Leipzig: Georg Thieme 1938.
Patterson, J. T.: The production of mutations in somatic cells of Drosophila melanogaster by means of X-rays. J. exp. Zool. 53, 327–372 (1929).
Revell, S. H.: The accurate estimation of chromatid breakage, and its relevance to a new interpretation of chromatid aberrations induced by ionizing radiations. Proc. roy. Soc. B 150, 563–589 (1959).
—: Chromatid aberrations—the generalized theory. In: S. Wolff (ed.), Radiation-induced chromosome aberrations, vol. 41. New York: Columbia Univ. Press 1963.
—: Evidence for a dose-squared term in the dose response curve for real chromatid discontinuities induced by X-rays, and some theoretical consequences there of. Mutation Res. 3, 34–53 (1966).
Sax, K.: Induction by X-rays of chromosome aberrations in Tradescantia microspores. Genetics 23, 494 (1938).
Shapiro, N. J.: X-ray dosage and frequency of somatic mosaics. Dros. Inf. Serv. 15, 17 (1941).
Stern, C.: Somatic crossing over and segregation in Drosophila melanogaster. Genetics 21, 625–730 (1936).
Timofeeff-Ressovsky, N. W., Zimmer, K. G.: Biophysik. I. Das Trefferprinzip in der Biologie. Leipzig: Hirzel 1947.
Ulrich, H.: A convenient method of collecting large numbers of Drosophila eggs homogenous in age. Dros. Inf. Serv. 27, 124–125 (1953).
Weinstein, A.: The theory of multiple-strand crossing over. Genetics 21, 155–199 (1936).
Wolff, S., Luippold, H. E.: The biochemical aspects of chromosome rejoining. In: J. S. Mitchell, B. E. Holmes, C. L. Smith (eds.), Progress in radiobiology, p. 217–221. Edinburgh: Oliver & Body 1956.
—: Radiation genetics. In: M. Errera, A. Forssberg (eds.), Mechanisms in radiobiology, vol. 1, p. 419. New York: Academic Press 1961.
Zimmer, K. G.: Studien zur quantitativen Strahlenbiologie. Akademie der Wissenschaften und der Literatur: Abhandlungen der math. naturwiss. KI. Mainz 1960.
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This and the following paper are dedicated to the memory of Dr. Jack Schultz.
Vorgelegt von Ch. Auerbach
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Haendle, J. Röntgeninduzierte mitotische Rekombination bei Drosophila melanogaster . Molec. Gen. Genetics 113, 114–131 (1971). https://doi.org/10.1007/BF00333185
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DOI: https://doi.org/10.1007/BF00333185