Question

Explain the regulation of gene expression in eukaryotic cells.

Discuss mechanisms by which gene expression may be altered.

How do these alterations induce cancer-causing mutations in cell DNA?

Explain how cancer is formed.

Describe genetic changes found in cancer cells and how these changes lead to alterations in cell behavior.

Determine whether proteome data can be utilized in genetic disorder diagnosis.

Relate the Human Genome Project data to the analysis of cancer genes.

Answer 1

As per our regulation the first full question is answered. Please get back for remaining questions.

Gene expression regulation in Eukaryotes:

The genes are the fundamental units which can code of various proteins, functional RNAs and shape an organism. The genes are present on strands of DNA in the form of complex arrangement of nucleotide bases and form what is called as Genome. These genes are always under control of regulatory proteins, which decide the time and dose of expression of the genes. The gene expression regulation is a critical aspect of successful cell functioning.
In eukaryotes, the regulation of gene expression takes place at 3 different levels.
A. At the level of transcription: here the initiation of gene expression is inhibited or blocked. The RNA polymerase is not allowed to bind to the promoter regions of the genes.
The genes are also regulated by chromosome remodelling. Here the chromosomes undergo structural changes to expose some part of the chromosome and closing the other. The genes in the exposed part are expressed. The genes are also controlled by activators or cis-acting elements.
B. Post-transcription level: In eukaryotes, the nascent mRNA is processed to give mature mRNA. This process is called splicing. The introns are removed and exons are joined together. The exon can be shuffled while joining to give rise to a different coding sequence and different protein. The mRNA can also be regulated by siRNA or miRNA.
C. Post-translation level: By modifying the polypeptide its function can be altered. The common alterations are phosphorylation, glycosylation...etc.