Yeast artificial chromosome

Yeast Artificial Chromosome (YAC) is a vector used in genetic engineering to clone DNA fragments that are larger than those cloned by other means. It is constructed from the telomeric, centromeric, and replication origin sequences needed for replication and preservation in yeast cells.

History

YACs were first described in 1987 by a team led by David T. Burke. They were used in the Human Genome Project, which aimed to map the entire human genome.

Structure and Function

A YAC is made up of a centromere, two telomeres, and an origin of replication. These are the necessary elements for replication and segregation during cell division. The YAC also contains a selectable marker gene, which is usually the suppressor tRNA gene SUP4. This gene allows for the selection of yeast cells that have been successfully transformed with the YAC.

Applications

YACs have been used in a variety of applications in genetic research. They were used extensively in the Human Genome Project, and have also been used to study the genetics of other organisms, such as yeast and mice. They have also been used in the study of diseases, such as cancer and Alzheimer's disease.

Limitations

While YACs have many advantages, they also have some limitations. They can be unstable, leading to the loss of inserted DNA. They can also undergo recombination, leading to the rearrangement of the inserted DNA. These limitations have led to the development of other cloning vectors, such as bacterial artificial chromosomes (BACs).

See Also

• Bacterial artificial chromosome
• Human Genome Project
• Genetic engineering

References

• Yeast_artificial_chromosome
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  Microtiter plates from Wash U Human YAC Library, 1993
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  Yeast artificial chromosome