Biology Reference
In-Depth Information
Fat Body
vg
vg
vg
d
s
RNA
vg
Abdomen
Figure 7.6.
Cartoon of the ef ect of injecting double-stranded RNA (dsRNA)
into the abdomen of a worker honey bee. RNA is normally found as a single
strand at er it is transcribed from the DNA in the nucleus of a cell. h e messenger
RNA migrates out of the nucleus and forms a template for protein synthesis in the
cell, a process called translation. h e dsRNA disrupts the translation process.
seems key to the phenotypic architecture of pollen hoarding and forag-
ing behavior (Figure 5.14). Gro Amdam and Ricarda Scheiner injected
newly emerged bees with
vg
dsRNA and tested them when they were 7
days old for their sucrose responses using the PER assay. Bees with re-
duced vitellogenin were more responsive to lower concentrations of sugar
and water than were the control bees.
At i rst, this i nding seemed contradictory to what we would have
predicted because high-strain bees have higher titers of Vg and are more
responsive throughout life. Vg knockdowns should have produced bees
that were more like low-strain bees. However, Tanya Pankiw has shown
that response to sugar increases with age and treatment with metho-
prene. Methoprene is an analog of JH that results in rapid behavioral
development and earlier onset of foraging. It is likely that the age ef ect
on sucrose response is modulated by JH, and JH is modulated by Vg.
