Biology Reference
In-Depth Information
A
Dopamine
sNPF
sNPF
high Ecd
Ecd
Low Ecd
ETH
Brain-CC-CA
CC-CA
CA
Ecdysteroid
1
2
3
4
0
1
2
4th
5th
B
C
Brain
80
AT
60
40
sNPF
CC
20
CA
0
JH
25°C
30°C
Figure 3.3 (A) Synthetic activity of JH by a brain
-
CC
-
CA complex, CC
-
CA complex, and
CA alone in Bombyx. Summary of the action of ecdysteroid, sNPF, ETH, and dopamine on
JH biosynthesis is shown on top. Note that the action of these factors are well cor-
responded to the synthetic activity by CC
-
CA complexes in the fourth instar stadium
(see text for discussion). Bolds: stimulative action, underlines: inhibitory action. (B) AT
activates the CA of Agrius convolvuli, a close relative of Manduca, only at high temper-
ature such as 30
C, but not at 25
C. CC
-
CA complexes from female day 0 adult were
cultured with or without 0.1 nM AT for 6 h followed by the measurement of JH synthetic
activity (N¼5, SE). The male CC
-
CA were not activated by AT even at 30
C. (C) The
mode of suppressive action of AT in Bombyx. The receptor for AT is expressed in the
same cells as sNPF cells in the CC, AT stimulates sNPF expression, and then the trans-
lated sNPF in the CC is transferred to the CA, where the sNPF receptor presents, through
the nerve axon to suppress JH biosynthesis.
