POU- and Homeo-domain proteins form a large class of important transcription factors. One of them is the POU domain protein, Class 4, transcription factor 3, or for short POU4F3. Despite the name, this protein contains a POU-domain and a Homeo-domain.
A POU4F3 molecule that is homologous with the one we (I mean you) will study in this project. Please be aware that it is difficult to crystallize protein-DNA complexes. Therefore the proteins tend to be incomplete in the structure files, and the DNA tends to be not the real motif but something else that crystallized well.
A large series of genetic disorders (inherited diseases) are known that are the result of "errors" in transcription factors. Obviously, we will never detect fatal errors in transcription factors that are crucial for life, but if something goes wrong in the genes that are responsible for, for example, the development of (parts of) eyes or ears, then the patient can live to be old, and the mutation can be detected, described, and deposited in (O)MIM.
In this "experiment" you are going to analyze a series of mutations
in the POU4F3 protein that all lead to deafness with different degrees of
severity and different onsets.
In the lab we purified and sequenced the cDNAs of a series of ESTs corresponding to the POU4F3 genes of patients with POU4F3 related deafness.
We expect you to analyze these mutations and to write a one-page-max report about the molecular origin of the deafness.
Question 1: A few questions to help you get started. What is a transcription factor? What is (O)MIM? What is cDNA and why do we need it? What is an EST?Answer