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Assimilatory induction by living cells of adult tissues in gastrula ectoderm of xenopus
216
215 ASS I M I L A T O R Y V I N G CELLS
INDUCTION
OF A D U L T
RULA ECTODERM
TISSUES
~Y
LI-
IN GAS T-
OF X E N O P L ~
G.V.Lopashov & O.N.Golubeva / I n s t i t u t e of G e n e r a l G e n e t i c s Ac. S ci.USSR, Gubkin St.3, Moscow II7809,
uss R/. An action
investigation of p r o d u c t s
living
tissues
made.
Lens
lasts
of a d u l t
wer
influence same
of a d u l t
epithelium
studied
frogs
amimals
was
tadpoles
of t r a n s f i l t e r
of g a s t r u l a
ectoderm
of the
results
of e x p e r i -
ments
s e e m to c o r r o b o r a t e
the a s s u m -
ption
that
tissues
many
types
inducing similar rula
The
from
and c a r d i o m y o b and
by m e a n s
species.
of i n d u c t i v e
emanating
cells
of a d u l t
prolonge
factors, tissues
Some factors affecting fecundity in Caryedon serratus (Coleoptera: Bruchidae) R P MALEYVAR AND A K CHAWLA We describe the effects of some extrinsic and intrinsic factors on the fecundity and the rate of survival of Caryedon serratus during development. Normally, oviposition lasts about 2 weeks but close to 90% eggs are laid within the first six days of oviposition. Maximum oviposition occurs generally on the 3rd day and the highest rate of survival was noted in the eggs laid on this day. Of the five varieties of seeds tried as substrata for egg-laying and development,Tamarindus indica was found to be the best ~ Greater fecundity and survival of the larval and pupal stages was noted at 28±2°C and 70% relative humidity. Mating, which occurs soon after the emergence of adults, triggers oviposition. Experimental oelays in mating (12 to 84 hours), drastically reduce the rates of oviposition as well as survival during the larval and pupal phases. The female body-weight ranging from 21-23 mg was noted to be related to optimal fecundity.
of
to s y n t h e s i z e
which
can
induce
in t o t i p o t e n t
gast-
The possible implications vations will be discussed.
ectoderm.
of
these
obser-
217
218
CONCANAVALIN A (CON A), PHYTOHEMAGGLUTININ (PHA), AND HYDRA GROWTH FACTOR (HGF) PROMOTE DI~'F~-.ENT PATTERNS OF NEURALIZATION IN AMPHIBIAN GASTRUIA ECTODERM.
EMBRYONIC BRAIN-DERIVED NEURALIZING FACTOR. A.T.Mikhailov, N.A.Gorgol,yuk. Institute of Developmental Biology USSR Acad. Sci., Moscow. Extracts from brain of 7-8 days old chick embryos were shown to possess a distinct neuralizing effect on amphibian gastrula ectoderm in vitro. Similar activity has been f ~ - ~ - ~ o in chick embryonic retina, but not in liver (Sov.J.Devl.Biol., 1980. 11, 3948). This neuralizing activit~T: (I) is extracted with distilled water at pH 9.0; (2) is non-dyalizable; (3) is found in 100,000 g supernatant of e x ~ facts; its effect depended on concentration of extracts in culture medium; (4) is preserved after lyophilization; (5) is RNAase-resistant, but protease sensitive; (6) is decreased after adsorption of extracts on nitrocellulose; (7) is not associated with NGF-like embryonic factors; (8) is decreased after absorption of extracts with Heparin-Sepharose; (9) is retained after absorption with Con A- or Protein ASepharose; (10) is preserved after electrophoretic separation or chromatography of extracts on DEAE-Toyopearl
Mi~hailov, A.T. Gorgolyuk. Institute of Developmental Biology USSR, Acact Sc., Moscow. Explants of R~na temporaria early gastrula ectoderm were treated with several mitogens. The following effects were observed: Con A: the lowest effective concentration was 75 pg/ml causing neurallzing effect (N-E) in 15% of explants. The m a x i m u m effect was at 100-200 pg/ml. Treatment of explants with Con A at 2o or 210 C produced similar effects (58% and 42%, respectively). PHA: NE was first noted at 6 ~g/ml and reached maximum of 47% at 25 #g/ml. Further increase in PHA concentration (50, I00, 200 #g/ml) resulted in a gradual decrease in NE (32%, 18% and 13%, respectively). EGF: NE was observed at 2.5, 25 and 250 #g/ml. The induction rate was not higher than 35%. The effect did not depend on HGF concenctratio~ It is proposed that the employed mitogens exert their NE via different mechanisms.
6 5 0 M.
$70
215 ASS I M I L A T O R Y V I N G CELLS
INDUCTION
OF A D U L T
RULA ECTODERM
TISSUES
~Y
LI-
IN GAS T-
OF X E N O P L ~
G.V.Lopashov & O.N.Golubeva / I n s t i t u t e of G e n e r a l G e n e t i c s Ac. S ci.USSR, Gubkin St.3, Moscow II7809,
uss R/. An action
investigation of p r o d u c t s
living
tissues
made.
Lens
lasts
of a d u l t
wer
influence same
of a d u l t
epithelium
studied
frogs
amimals
was
tadpoles
of t r a n s f i l t e r
of g a s t r u l a
ectoderm
of the
results
of e x p e r i -
ments
s e e m to c o r r o b o r a t e
the a s s u m -
ption
that
tissues
many
types
inducing similar rula
The
from
and c a r d i o m y o b and
by m e a n s
species.
of i n d u c t i v e
emanating
cells
of a d u l t
prolonge
factors, tissues
Some factors affecting fecundity in Caryedon serratus (Coleoptera: Bruchidae) R P MALEYVAR AND A K CHAWLA We describe the effects of some extrinsic and intrinsic factors on the fecundity and the rate of survival of Caryedon serratus during development. Normally, oviposition lasts about 2 weeks but close to 90% eggs are laid within the first six days of oviposition. Maximum oviposition occurs generally on the 3rd day and the highest rate of survival was noted in the eggs laid on this day. Of the five varieties of seeds tried as substrata for egg-laying and development,Tamarindus indica was found to be the best ~ Greater fecundity and survival of the larval and pupal stages was noted at 28±2°C and 70% relative humidity. Mating, which occurs soon after the emergence of adults, triggers oviposition. Experimental oelays in mating (12 to 84 hours), drastically reduce the rates of oviposition as well as survival during the larval and pupal phases. The female body-weight ranging from 21-23 mg was noted to be related to optimal fecundity.
of
to s y n t h e s i z e
which
can
induce
in t o t i p o t e n t
gast-
The possible implications vations will be discussed.
ectoderm.
of
these
obser-
217
218
CONCANAVALIN A (CON A), PHYTOHEMAGGLUTININ (PHA), AND HYDRA GROWTH FACTOR (HGF) PROMOTE DI~'F~-.ENT PATTERNS OF NEURALIZATION IN AMPHIBIAN GASTRUIA ECTODERM.
EMBRYONIC BRAIN-DERIVED NEURALIZING FACTOR. A.T.Mikhailov, N.A.Gorgol,yuk. Institute of Developmental Biology USSR Acad. Sci., Moscow. Extracts from brain of 7-8 days old chick embryos were shown to possess a distinct neuralizing effect on amphibian gastrula ectoderm in vitro. Similar activity has been f ~ - ~ - ~ o in chick embryonic retina, but not in liver (Sov.J.Devl.Biol., 1980. 11, 3948). This neuralizing activit~T: (I) is extracted with distilled water at pH 9.0; (2) is non-dyalizable; (3) is found in 100,000 g supernatant of e x ~ facts; its effect depended on concentration of extracts in culture medium; (4) is preserved after lyophilization; (5) is RNAase-resistant, but protease sensitive; (6) is decreased after adsorption of extracts on nitrocellulose; (7) is not associated with NGF-like embryonic factors; (8) is decreased after absorption of extracts with Heparin-Sepharose; (9) is retained after absorption with Con A- or Protein ASepharose; (10) is preserved after electrophoretic separation or chromatography of extracts on DEAE-Toyopearl
Mi~hailov, A.T. Gorgolyuk. Institute of Developmental Biology USSR, Acact Sc., Moscow. Explants of R~na temporaria early gastrula ectoderm were treated with several mitogens. The following effects were observed: Con A: the lowest effective concentration was 75 pg/ml causing neurallzing effect (N-E) in 15% of explants. The m a x i m u m effect was at 100-200 pg/ml. Treatment of explants with Con A at 2o or 210 C produced similar effects (58% and 42%, respectively). PHA: NE was first noted at 6 ~g/ml and reached maximum of 47% at 25 #g/ml. Further increase in PHA concentration (50, I00, 200 #g/ml) resulted in a gradual decrease in NE (32%, 18% and 13%, respectively). EGF: NE was observed at 2.5, 25 and 250 #g/ml. The induction rate was not higher than 35%. The effect did not depend on HGF concenctratio~ It is proposed that the employed mitogens exert their NE via different mechanisms.
6 5 0 M.
$70