Yeast artificial chromosome

This article is about Chromosomes derived from yeast DNA. For Yeast created from synthetic DNA, see Synthetic DNA.

Yeast artificial chromosomes (YACs) are genetically engineered chromosomes derived from the DNA of the yeast, Saccharomyces cerevisiae [1], which is then ligated into a bacterial plasmid. By inserting large fragments of DNA, from 100–1000 kb, the inserted sequences can be cloned and physically mapped using a process called chromosome walking. This is the process that was initially used for the Human Genome Project, however due to stability issues, YACs were abandoned for the use of bacterial artificial chromosome [2]

The bakers' yeast S. cerevisiae is one of the most important experimental organisms for studying eukaryotic molecular genetics.[1]

Beginning with the initial research of the Rankin et al., Strul et al., and Hsaio et al., the inherently fragile chromosome was stabilized by discovering the necessary autonomously replicating sequence (ARS);[2] a refined YAC utilizing this data was described in 1983 by Murray et al.[3]

The primary components of a YAC are the ARS, centromere [3], and telomeres [4] from S. cerevisiae. Additionally, selectable marker genes, such as antibiotic resistance and a visible marker, are utilized to select transformed yeast cells. Without these sequences, the chromosome will not be stable during extracellular replication, and would not be distinguishable from colonies without the vector.[4]

This is a photo of two copies of the Washington University Human Genome YAC Library. Each of the stacks is approximately 12 microtiter plates. Each plate has 96 wells, each with different yeast clones.
  1. ^ The Molecular biology of the yeast Saccharomyces: metabolism and gene expression. Cold Spring Harbor, N.Y: Cold Spring Harbor Laboratory. 1982. ISBN 0-87969-149-2.
  2. ^ Hsiao CL, Carbon J (August 1979). "High-frequency transformation of yeast by plasmids containing the cloned yeast ARG4 gene". Proceedings of the National Academy of Sciences of the United States of America. 76 (8): 3829–33. Bibcode:1979PNAS...76.3829H. doi:10.1073/pnas.76.8.3829. PMC 383928. PMID 386351.
  3. ^ Murray AW, Szostak JW (1983). "Construction of artificial chromosomes in yeast". Nature. 305 (5931): 189–93. Bibcode:1983Natur.305..189M. doi:10.1038/305189a0. PMID 6350893. S2CID 4337825.
  4. ^ Ratzkin B, Carbon J (February 1977). "Functional expression of cloned yeast DNA in Escherichia coli". Proceedings of the National Academy of Sciences of the United States of America. 74 (2): 487–91. Bibcode:1977PNAS...74..487R. doi:10.1073/pnas.74.2.487. PMC 392314. PMID 322128.