YCP contains Amp resistance gene and leuZ gene, so that they can be selected both in E coli and in yeast. Apart from these, YCP also contains a single copy of ARS sequence. Functionally YCPs exhibit the characteristics of chromosomes in yeast cells.

First, they are mitotically stable in the absence of selective pressure. Second, they segregate during meiosis in a Mendelian manner.

Finally, they are found at low copy number in the host cell. These vectors are used when the gene product is deleterious to the cell or when complementation studies are required. Low copy number makes recovery of plasmid from yeast very easy.