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Inhibition of ovary development of the fruit-fly, drosophila melanogaster by synthetic “Queen substance”
Life Sciences Vol. 8, Part II, pp. 785-789, 1989. Printed in Great Britain.
Pergamon Press
INHIBITION OF OVARY DEVELOPMENT ~ THE FRUIT-FLY, DROSOPHILA MELANOGASTER BY SYNTHETIC "QUEEN SUBSTANCE" A . Sannasi Department of Entomology, University of Georgia, Athens, U.S .A . (Received 28 March 1989 ; in final form 9 May 1989) Recent investigations have shown the important regulatory role of pheromones xithin the colony of social lnaeats.
Some pheromones
have been isolated and characterized and among these "queen substance", eztraeted from queen honey bees and identified as (9-osodea- trans-2-enoie acid) 1 partially inhibits the development of the ovaries in xorker honey bees and influences their behaviour by inhibiting queen-sell construction .
Inter, investigators re-
ported the inhibitory effeat of "queen substance" on ovary development in other groups of social insects ae in the xorker of the ant, Formica fusca L, 2 and the termite, äalotermes f laviaollie 3. It appears to be effective in non-social insects also like females of the bouée-fly, Musas damestica L, 4 and the pram, Leander 2 serratua . The inhibitory effeat of synthetic "queen substance" on oogenesis and the correlated changea in the corpora allata in females of the fruit-fly, Drosophila melanoaaster are reported in this paper . Ezperimental Procedure The ovaries of nexly emerged flies are immature and contain no ripe eggs .
Each ovary Sa made up of 15 to 20 ovariolea 5 .
Yheit
nexly emerged female flies xere 7 to 10 hours old, samples of 25 flies each xere in~eated in the thoraz xith 3
785
~tl
per fly of a 2 mg/ml
SYNTHETIC QUEEN SUBSTANCE
788
voi. 8, No. 14
of dilute ethanolic solution of synthetic "queen substance", and in~ectiona xere made repeatedly at the time-intervals shorn in Table 1 .
Higher concentrations of synthetic "queen substance"
xere found to be tout and loxer concentrations failed to elicit at~y noticeable effect on the inhibition of ovary development in the fruit-fly.
The treated and control flies xere alloxed to
feed on the nutrient medium xhich consists of I80 ml xater, $ g agar, 65 ml corn soup and 250 ml tomato juice then dissected and the ovaries measured .
6.
The flies xere
Results are reported in
Table i xhich ahoKa the effect of synthetic "queen substance" on the ovary development of the fruit-fly . TABIB 1 Effect of Injection of Synthetic "Queen Substance" on Ovary Development and Mortality of the Fruit-Fly, Drosophila melanogaster Treatment of flies 25 flies per test Material injected} None Queen substance" Distilled rater queen substance" Distilled rater "Queen substance" Distilled rater "Queen substance" Distilled rater
Times of Injection (hours)
Mean dimensions of ovaries (mm)+ length xidth
_
0.5
0 0,24 0,24 0,48 0,24,48 0,24,48 0,24,48
1 .5 2,0 1 .4 1 .2 1 .8 0 .5
0
0.~
i .o
0 .3 0,4 0 .7 1,0 0,7 0,8 0 .5 0,2 0,3
Percentage of mortality after 96 hours ioo
46 0 46 0 10 io io
0
* 3 ~1/fly of a solution of 2 mg/ml of synthetic "queen substance" dissolved in 5 per cent ethanolic solution xae injected in flies in testa 2,4,6 and 8 . Equivalent volume of distilled rater ras injected in testa 3,5,7 and 9 . All flies ezcept the teat i xere fed for a total period of 96 hours . + Means are based on measurements of flies randomly selected from each of five repl~.oated tests involving 25 flies .
Vol . 8, No . 14
SYNTHETIC QUEEN SUBSTANCE
787
Results and Diacuanion These results shox that continuous availability of a pertain amount of synthetic "queen substance " in the insect body is essential for complete inhibition of ovary development in the fruit-fly .
Since synthetio "queen substance" appears to be meta-
bolized or ezareted by the fruit-fly rapidly, it must be supplied Othex~riae its inhibitory effect xeara off .
at regular intervals .
This effect of synthetic "queen aubstanoe" appears to be similar to that on honey bees where the xorker bees must continuously obtain "queen aubstanoe" from the queen bee for inhibition of ovary development, It is xell knoxn that corpora allata control the maturity of oogeneais in inaeota 7,
In the present study it has been found
that synthetic"queen substance" inhibits oogeneais in the nexly emerged fruit-flies,
In the light of these facts, it is reasonable
to presume that corpora allata of fruit-f ly may ezert an influenoe on the maturity of oogenesis .
With this Sa mind, a preliminary
attempt xas made to study the seeretory activity of the corpora spats of the treated and control flies, Flies xhich received infections of synthetic "queen substance" xere used both for histologioal studies as xell as for measuring the ovarian . The histological material xas stained xith aldehyde 8 fuehsin . The addition of Weigert~s haematoaylin as a nucleus stain permitted the use of the sections for nuclear counts as well as a study of seeretory products .
As a basis for comparison
of the morphological characteristics of the corpora spats, three values namely the volume of glands, the total number of nuclei and their relative number per unit of tissue (nuclear-eytoplasmic
ratio) were determined by the method of Scharrer and Von Harneck 9 . It was found that there is a marked decrease in the seeretory
788
SYNTHETIC QUEEN SUBSTANCE
Vol. 8, No. 14
activity of corpora allata in the flies xhich received synthetic "queen substance" compared to the normal ones .
These results
suggest that inhibition of ovary development by the synthetic "queen substance" is brought about by an action upon the corpora spats xhich thereby prevented from secreting the "gonodotropic" hormone . Summary Synthetic "queen substance" inhibits maturation of ovary in females of the fruit-fly, Drosophüs melanogaster ,
The secretory
activity of corpora al].ata of the fruit-flies which received synthetic "queen substance" seems to àearease, Açlrnoxledgements I wish to thank Dr . R .K . Callax, F,R,S for providing a sample of 9-ozodec-trans -2-enoic acid, synthesized by Glazo laboratories,
I am grateful to Dr . Mousy 3, Blum for helpful
suggestions in this xork, References C,G, Butler, R .K . CALLOW and N .C, JOHNSTON, Pro,Roy,Soc, B 41~ (1961) . 2.
D,B. CARLSILE and C,G . BUTLER, Natur® ~, 276 (1956),
3.
I . HRDY, V.J .A, NOVAK and D, SKROBAL, Acta Symposia de Evolutione insectorum , Prague, p, 172 (1960),
4.
J .K . NAYAR, Nature ~, 923 (1963) .
5,
D . BODENSTEIN, Post-embryonic Development of Drosophila in Biology of Drosophila , Edit, by M . DEMERC, p, 305, Wiley, New York (1950),
6.
A. ROTIiSCHILD, W,V . EISENBERG and A,W . VAQUEZ, J . Heredity 98 (1968) .
Vol. 8, No. 14
SYNTHETIC QUEEN SUBSTANCE
789
V,B . WIGGLESWORTH, The control of groxth and form ( Cornell University Press, 1959) . 8.
G . GOMORI, Amer . J . Clin . Path, ~, 665 (1950) .
9.
B . SCHARRER and M . VON HARNALK, Biol . Bull, Woods Hole ice, 508 (1958) .
Pergamon Press
INHIBITION OF OVARY DEVELOPMENT ~ THE FRUIT-FLY, DROSOPHILA MELANOGASTER BY SYNTHETIC "QUEEN SUBSTANCE" A . Sannasi Department of Entomology, University of Georgia, Athens, U.S .A . (Received 28 March 1989 ; in final form 9 May 1989) Recent investigations have shown the important regulatory role of pheromones xithin the colony of social lnaeats.
Some pheromones
have been isolated and characterized and among these "queen substance", eztraeted from queen honey bees and identified as (9-osodea- trans-2-enoie acid) 1 partially inhibits the development of the ovaries in xorker honey bees and influences their behaviour by inhibiting queen-sell construction .
Inter, investigators re-
ported the inhibitory effeat of "queen substance" on ovary development in other groups of social insects ae in the xorker of the ant, Formica fusca L, 2 and the termite, äalotermes f laviaollie 3. It appears to be effective in non-social insects also like females of the bouée-fly, Musas damestica L, 4 and the pram, Leander 2 serratua . The inhibitory effeat of synthetic "queen substance" on oogenesis and the correlated changea in the corpora allata in females of the fruit-fly, Drosophila melanoaaster are reported in this paper . Ezperimental Procedure The ovaries of nexly emerged flies are immature and contain no ripe eggs .
Each ovary Sa made up of 15 to 20 ovariolea 5 .
Yheit
nexly emerged female flies xere 7 to 10 hours old, samples of 25 flies each xere in~eated in the thoraz xith 3
785
~tl
per fly of a 2 mg/ml
SYNTHETIC QUEEN SUBSTANCE
788
voi. 8, No. 14
of dilute ethanolic solution of synthetic "queen substance", and in~ectiona xere made repeatedly at the time-intervals shorn in Table 1 .
Higher concentrations of synthetic "queen substance"
xere found to be tout and loxer concentrations failed to elicit at~y noticeable effect on the inhibition of ovary development in the fruit-fly.
The treated and control flies xere alloxed to
feed on the nutrient medium xhich consists of I80 ml xater, $ g agar, 65 ml corn soup and 250 ml tomato juice then dissected and the ovaries measured .
6.
The flies xere
Results are reported in
Table i xhich ahoKa the effect of synthetic "queen substance" on the ovary development of the fruit-fly . TABIB 1 Effect of Injection of Synthetic "Queen Substance" on Ovary Development and Mortality of the Fruit-Fly, Drosophila melanogaster Treatment of flies 25 flies per test Material injected} None Queen substance" Distilled rater queen substance" Distilled rater "Queen substance" Distilled rater "Queen substance" Distilled rater
Times of Injection (hours)
Mean dimensions of ovaries (mm)+ length xidth
_
0.5
0 0,24 0,24 0,48 0,24,48 0,24,48 0,24,48
1 .5 2,0 1 .4 1 .2 1 .8 0 .5
0
0.~
i .o
0 .3 0,4 0 .7 1,0 0,7 0,8 0 .5 0,2 0,3
Percentage of mortality after 96 hours ioo
46 0 46 0 10 io io
0
* 3 ~1/fly of a solution of 2 mg/ml of synthetic "queen substance" dissolved in 5 per cent ethanolic solution xae injected in flies in testa 2,4,6 and 8 . Equivalent volume of distilled rater ras injected in testa 3,5,7 and 9 . All flies ezcept the teat i xere fed for a total period of 96 hours . + Means are based on measurements of flies randomly selected from each of five repl~.oated tests involving 25 flies .
Vol . 8, No . 14
SYNTHETIC QUEEN SUBSTANCE
787
Results and Diacuanion These results shox that continuous availability of a pertain amount of synthetic "queen substance " in the insect body is essential for complete inhibition of ovary development in the fruit-fly .
Since synthetio "queen substance" appears to be meta-
bolized or ezareted by the fruit-fly rapidly, it must be supplied Othex~riae its inhibitory effect xeara off .
at regular intervals .
This effect of synthetic "queen aubstanoe" appears to be similar to that on honey bees where the xorker bees must continuously obtain "queen aubstanoe" from the queen bee for inhibition of ovary development, It is xell knoxn that corpora allata control the maturity of oogeneais in inaeota 7,
In the present study it has been found
that synthetic"queen substance" inhibits oogeneais in the nexly emerged fruit-flies,
In the light of these facts, it is reasonable
to presume that corpora allata of fruit-f ly may ezert an influenoe on the maturity of oogenesis .
With this Sa mind, a preliminary
attempt xas made to study the seeretory activity of the corpora spats of the treated and control flies, Flies xhich received infections of synthetic "queen substance" xere used both for histologioal studies as xell as for measuring the ovarian . The histological material xas stained xith aldehyde 8 fuehsin . The addition of Weigert~s haematoaylin as a nucleus stain permitted the use of the sections for nuclear counts as well as a study of seeretory products .
As a basis for comparison
of the morphological characteristics of the corpora spats, three values namely the volume of glands, the total number of nuclei and their relative number per unit of tissue (nuclear-eytoplasmic
ratio) were determined by the method of Scharrer and Von Harneck 9 . It was found that there is a marked decrease in the seeretory
788
SYNTHETIC QUEEN SUBSTANCE
Vol. 8, No. 14
activity of corpora allata in the flies xhich received synthetic "queen substance" compared to the normal ones .
These results
suggest that inhibition of ovary development by the synthetic "queen substance" is brought about by an action upon the corpora spats xhich thereby prevented from secreting the "gonodotropic" hormone . Summary Synthetic "queen substance" inhibits maturation of ovary in females of the fruit-fly, Drosophüs melanogaster ,
The secretory
activity of corpora al].ata of the fruit-flies which received synthetic "queen substance" seems to àearease, Açlrnoxledgements I wish to thank Dr . R .K . Callax, F,R,S for providing a sample of 9-ozodec-trans -2-enoic acid, synthesized by Glazo laboratories,
I am grateful to Dr . Mousy 3, Blum for helpful
suggestions in this xork, References C,G, Butler, R .K . CALLOW and N .C, JOHNSTON, Pro,Roy,Soc, B 41~ (1961) . 2.
D,B. CARLSILE and C,G . BUTLER, Natur® ~, 276 (1956),
3.
I . HRDY, V.J .A, NOVAK and D, SKROBAL, Acta Symposia de Evolutione insectorum , Prague, p, 172 (1960),
4.
J .K . NAYAR, Nature ~, 923 (1963) .
5,
D . BODENSTEIN, Post-embryonic Development of Drosophila in Biology of Drosophila , Edit, by M . DEMERC, p, 305, Wiley, New York (1950),
6.
A. ROTIiSCHILD, W,V . EISENBERG and A,W . VAQUEZ, J . Heredity 98 (1968) .
Vol. 8, No. 14
SYNTHETIC QUEEN SUBSTANCE
789
V,B . WIGGLESWORTH, The control of groxth and form ( Cornell University Press, 1959) . 8.
G . GOMORI, Amer . J . Clin . Path, ~, 665 (1950) .
9.
B . SCHARRER and M . VON HARNALK, Biol . Bull, Woods Hole ice, 508 (1958) .