Isolation and partial characterization of the Kluyveromyces lactis homologue of SKP1

The SKP1 gene of Kluyveromyces lactis was isolated as a suppressor of a let hal temperature-sensitive mutation in the Saccharolmyces cervisiae CTF13 ge ne (Chromosome Transmission Factor 13). klSKkP1 was localized at chromosome V, adjacent to KlPAS3. A similar arrangement of the two genes is present i n S. cerevisiae. Disruption of the KlSKP1 gene was lethal, whereas overexpr ession of KlSKP1 lead to a decreased growth rate, to swollen and chain-form ing cells with an increased DNA content, and to decreased plasmid stability . In both yeasts, promoter constructs lacking most of the purported binding sequence showed increased transcription levels of klSKP1 in comparison to constructs with the entire promoter.