Question

Can someone please explain to me in simple words the article "Products of DNA mismatch repair genes mutS and mutL are required for transcription-coupled nucleotide-excision repair of the lactose operon in Escherichia coli ?

Answer 1

The molecular details of nucleotide excision repair and the methyl-directed mismatch repair are two DNA repair mechanism found in prokaryotes like E. coli have been well. The experiments elucidates of the two functionally, genetically and evolutionary distinct mechanism that couples in DNA repair and implicate components of DNA mismatch, by causing mutation at several different DNA repair genes on the removal of cyclobutane pyrimidine dimers from the individual strands of the induced lactose operon in UV-irradiated Escherichia coli. The paper dicusses the finding in the experiments and the key takeaways are:

1. MutS and MutL of mismsth repaire mechanism are involved in the processing of UV-induced photoproducts.
2. An additional mechanism acts in concert with Non homologous End joinng Repair to accelerate the removal of transcription-blocking lesions in the transcribed strands of active genes and the mismatch repair proteins are directly involved in transcription-coupled repair