Z DNA is a left-handed helical structure of DNA that is different from the more common B-DNA form. It is characterized by a zigzag pattern and contains 12 base pairs per helical turn. While B-DNA is right-handed, Z-DNA winds to the left. It is often found in alternating purine-pyrimidine sequences, such as GCGCGC.
Z-DNA is thought to be a minor component of the DNA in a cell but is believed to play a role in gene regulation and other cellular processes.
Z-DNA was discovered by Alexander Rich in 1979, who used X-ray crystallography to determine its structure.
Practical Insights:
- The discovery of Z-DNA led to a better understanding of the complexity of DNA and its ability to take on different forms.
- Scientists are still studying the role of Z-DNA in the cell, but it is thought to be involved in various processes, including:
- Gene regulation: Z-DNA may play a role in turning genes on and off.
- DNA replication: Z-DNA may be involved in the copying of DNA.
- DNA repair: Z-DNA may be involved in the repair of damaged DNA.
Examples:
- Interferons: Interferons are proteins that are involved in the immune response. Some interferons bind to Z-DNA, which suggests that Z-DNA may be involved in the regulation of the immune system.
