Alternative splicing of two translesion synthesis DNA polymerases from Arabidopsis thaliana.

DNA damages can be removed by different repair processes, but lesions sometimes remain and block DNA replication. Specialized polymerases are needed to overcome this difficulty. In Arabidopsis, AtPOLH and AtREV1 genes code for two polymerases that are involved in replication of damaged DNA. Alternative splicing was detected in both genes. Complementation analysis of the alternative splicing forms in Saccharomycescerevisiae showed that the C-terminal extreme of AtPOLH protein is essential for recovering wild type UV viability in Rad30 deficient strain. None of the alternative AtREV1 forms recovered the yeast wild type phenotype of Rev1 deficient yeast strains after UV light irradiation or methyl methane sulphonate exposition, suggesting that AtREV1 may not be able to interact with other yeast specific proteins needed for DNA translesion synthesis.