Bicoid action in drosophila

Bicoid action in DrosophilaBy: Fiona Marie Nuestro

We we look at how “Bicoid” can refer to as a gene, mRNA, or protein made from that gene. All three of these will be used to determine the head end of a developing Drosophila embryo.

Below is a chart showing the embryo development of the egg, eventually resulting into Drosophila..

nucleus cell

Depleted nurse cells

Bicoid mRNA

FertilizationLaying of egg

Anteriorend

1) Egg Cell

•mRNA carries a genetic message from the nurse cell DNA. It is produced by the nurse cells and is transported to the egg via cytoplasmic bridges and placed on the cytoskeleton at the anterior end of the egg.

•The cytoplasmic bridges and cytoskeleton act like the nuclear pores on the nucleus.

Anteriorend

2) Unfertilized

egg

•The bicoid mRNA is highly concentrated at the anterior end of the mature egg. The bicoid normally codes for a morphogen that creates the anterior which is the head end of the embryo.

•During fertilization, the egg activation is triggered by the binding and fusion of sperm.

•The sperm contributes to the embryo’s DNA.

FertilizationLaying of Egg

Next step

Anteriorend

3) Fertilized egg

•After egg is fertilized, meaning that the mRNA molecule reached the egg, egg ribosomes translate the mRNA’s genetic message into protein.

•This process is transcribing and translating the genetic information.

Continuation of Step 3: Fertilized

egg•Transcription factors are regulatory proteins that bind to DNA and affects transcription of specific genes.

•The specific transcription factors made in the cell determine which genes are expressed.•The Bicoid gene is expressed in this case.

•The bicoid gene is useful for creating the anterior end of a Drosophila.

Anteriorend

In the end, we result with the head of the

Drosophila if there is no mutant gene.