Biology Topic 8 : Determining protein sequences , non coding DNA and regulatory genes

What is a proteome?

Is all the protines an organism can make

How do scientists obtain a proteome?

They sequence the genome (determining the sequence of bases of all the DNA) and use computers to predict which protines the genes code for

why are bacteri and viruses used for proteome studies?

They have small genomes, no introns and simple gene regulation (turning genes on and off), so their DNA is much easier to analyse

What can scientists do once the genome is known?

They can use bioinformatics (computer analysis) to identify genes and predict the amino acid sequences of protines

What else can proteome data show other than predict the amino acid sequence of protines?

Shows which protines are actually expressed in different conditions e.g during infection

How does proteome data help vaccine development?

It helps scientists find antigens — protines on the pathogens surface that trigger an immune resposnse

What makes a good antigen for a vaccine?

A protine that is - on the surface, unique to the pathogen and able to stimulate immunity

How do scientists identify antigens from a pathogens genome?

They sequence the pathogens DNA , predict its proteome and look for proteins that match the criteria for antigens

How was sequencing pathogen DNA to predict its proteome to find protines that match the criteria for antigens , used in maleria vaccine development?

Theousands of Plasmodium falciparum genomes were sequenced to find genes with high varation which often code for imporant surface antigens

What does the RTS,S malaria vaccine target?

RTS,S targets a surface protein from the malaria parasite.

What is the genome?

Complete set of genes or genetic material in an organism

What does the genome do?

Provides the instructions for making all RNA and all proteins

What is the transcriptome?

All the mRNA molecules made from from the genome at a given time

Why is the transcriptome useful?

It shows which genes are being expressed (switched on) in a cell at that moment

What is the proteome?

All the proteins an organism or cell actually makes

How does the proteome relate to the transcriptome?

The trascriptome (mRNA) is translated to make the proteome (protines)

Why is the proteome important? Why can the proteome change?

Protines carry out all cell functions

Different genes are switched on / off depending on conditions so different protines are made

Why is the proteome more complex than the genome?

Becouse one gene can make multiple protines e.g alternative splicing , modifcation

How do scientists study the proteome?

By sequencing the genome, analysing mRNA and identifying which protines are produced in different conditions