Discovered enzyme able to replicate damaged DNA strands
The DNA of each of our cells encodes our genes , and is both the instruction manual that defines the alternatives of expression associated with cell differentiation in our tissues . DNA polymerases are the enzymes that synthesize DNA, not only by replicating the same , but also carrying out the repairs necessary for the proper maintenance of information .
" The most valuable feature of these enzymes is their fidelity copying. However, to have an intact DNA template for your copy is not always possible , either by defects in the machinery repair , or the intensity of genotoxic damage just by altering the code and even produces strand breaks . To address this problem , there is a group of specialized enzymes that copy and tolerate various forms of damage in DNA. PrimPol is probably DNA polymerase oldest human traslesión and early able to initiate the synthesis of new chains from deoxynucleotide units , "said CSIC researcher Luis Blanco , Center for Molecular Biology Severo Ochoa , CSIC joint center and the Autonomous University of Madrid.
According to this study , copying damaged DNA strand involves the introduction of mutations that might have an impact on the aging of cells , but it also plays a crucial role in genome evolution and diversification of life in the earth.
"This new human DNA polymerase , which is present both in the nucleus and in the mitochondria of our cells, probably arose during evolution as an early solution to the need to replicate DNA in our metabolic damage environments , as in the inside mitochondria , "says White .
By analyzes in human and murine cells , investigators have found that the silencing or removal of PrimPol affect mitochondrial DNA replication , suggesting that there PrimPol mutations that may be associated with human mitochondriopathies .
The study also involved the National Cancer Research Center , the University of La Laguna and the Medical Research Council in the UK .
* Sara García -Gómez , Aurelio Reyes , Maria I. Martinez - Jimenez, E. Sandra Chocrón , Silvana mouron , Gloria Terrados , Christopher Powell , Eduardo Salido, Juan Mendez , Ian J. Holt , Luis Blanco. PrimPol , an Archaic Primase / Operating Polymerase in Human Cells. Molecular Cell. DOI: 10.1016/j.molcel.2013.09.025