Indirect control of yolk protein genes by 20-hydroxyecdysone in the fat body of the mosquito, Aedes aegypti. Academic Article uri icon

Overview

MeSH

  • Animals
  • Cycloheximide
  • Female
  • Organ Culture Techniques
  • RNA, Messenger
  • Rats

MeSH Major

  • Aedes
  • Carboxypeptidases
  • Ecdysterone
  • Fat Body
  • Gene Expression Regulation
  • Insect Proteins
  • Vitellogenins

abstract

  • In response to a blood meal, the fat body of the female mosquito, Aedes aegypti, begins massive production of several yolk proteins which are subsequently stored in the developing oocytes. Although 20-hydroxyecdysone (20E) is important for initiation and maintenance of expression of the yolk protein genes encoding vitellogenin (Vg) and vitellogenic carboxypeptidase (VCP), the exact nature of 20E action has not been clearly defined. A primary question is whether this hormone directly stimulates expression of the genes for Vg and VCP or if it acts indirectly through a hormone response cascade. We have demonstrated that 10(-4) M cycloheximide (Chx) reversibly inhibits > 98% of protein synthesis in in vitro fat body culture. 10(-5) M 20E stimulates high levels of the mRNAs for Vg and VCP in previtellogenic fat bodies cultured in vitro, but initiation of this expression is eliminated by Chx. Thus, our results indicate that protein synthesis is required in response to 20E before increased levels of yolk protein mRNAs can be measured. We therefore conclude that the action of 20E is indirect.

publication date

  • April 1995

has subject area

  • Aedes
  • Animals
  • Carboxypeptidases
  • Cycloheximide
  • Ecdysterone
  • Fat Body
  • Female
  • Gene Expression Regulation
  • Insect Proteins
  • Organ Culture Techniques
  • RNA, Messenger
  • Rats
  • Vitellogenins

Research

keywords

  • Journal Article

Identity

Language

  • eng

PubMed ID

  • 7742832

Additional Document Info

start page

  • 449

end page

  • 454

volume

  • 25

number

  • 4