Kannouche, P. L., Wing, J. and Lehmann, A. R. (2004) Interaction of Human DNA Polymerase h with Monoubiquitinated PCNA; A Possible Mechanism for the Polymerase Switch in Response to DNA Damage. Molecular Cell, 14 (4). pp. 491-500. ISSN 1097-2765Full text not available from this repository.
Most types of DNA damage block replication fork progression during DNA synthesis because replicative DNA polymerases are unable to accommodate altered DNA bases in their active sites. To overcome this block, eukaryotic cells employ specialized translesion synthesis (TLS) polymerases, which can insert nucleotides opposite damaged bases. In particular, TLS by DNA polymerase eta (poleta) is the major pathway for bypassing UV photoproducts. How the cell switches from replicative to TLS polymerase at the site of blocked forks is unknown. We show that, in human cells, PCNA becomes monoubiquitinated following UV irradiation of the cells and that this is dependent on the hRad18 protein. Monoubiquitinated PCNA but not unmodified PCNA specifically interacts with poleta, and we have identified two motifs in poleta that are involved in this interaction. Our findings provide an attractive mechanism by which monoubiquitination of PCNA might mediate the polymerase switch.
|Depositing User:||Gee Wheatley|
|Date Deposited:||20 Mar 2007|
|Last Modified:||30 Nov 2012 16:51|
|Google Scholar:||439 Citations|