The REV1 gene of Saccharomyces cerevisiae: isolation, sequence, and functional analysis

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• The Saccharomyces cerevisiae REV1 gene plays a critical role in the cellular response to DNA damage induced by mutagens.
• Understanding the molecular mechanisms of REV1 is essential for comprehending DNA repair pathways and mutagenesis.

Purpose of the Study:

• To determine the DNA sequence of the REV1 gene and characterize its functional properties.
• To investigate the molecular basis of the rev1-1 mutant phenotype.

Main Methods:

• DNA sequencing of a 3,485-base-pair segment complementing the rev1-1 mutant.
• Gene disruption and creation of deletion mutants to confirm gene function and assess mutability.
• Analysis of the open reading frame, transcript length, and protein characteristics.
• Fusion of REV1 with the lacZ gene to study gene expression.

Main Results:

• The complete DNA sequence of REV1 was determined, revealing a 985-amino acid open reading frame and a 3.1 kb transcript.
• Frameshift mutations in the open reading frame resulted in a Rev-phenotype, while a specific base substitution (Gly-193 to Arg-193) was identified in the rev1-1 mutant.
• Deletion mutants showed varying mutability, and REV1 was confirmed as non-essential.
• The predicted REV1 protein is hydrophilic with a high pI, lacking homology to RAD proteins but showing partial identity to UMUC.

Conclusions:

• The characterized REV1 gene sequence and its mutations provide insights into its role in DNA repair and mutagenesis.
• REV1's non-essential nature and partial homology to UMUC suggest complex roles in DNA damage tolerance.