The elongation factor 1A: a novel regulator in the DNA replication/repair protein network in wheat cells?

Proliferating cell nuclear antigen (PCNA) is a DNA sliding clamp interacting with multiple partners in DNA transactions such as DNA replication/repair and recombination as well as chromatin assembly. We previously detected and purified by chromatographic procedures a 31 kDa PCNA from cultured wheat cells (Triticum monococcum L). Here we report the complete sequence of the wheat 31 kDa PCNA showing a very high aminoacid identity with its plant counterparts (maize and rice). This recombinant PCNA has been used as a bait in an affinity chromatography procedure, in order to capture PCNA interacting proteins. We detected by liquid chromatography, tandem mass spectrometry and search in plant protein databases, several specific bands from wheat cell lysates in fractions bound to wheat PCNA-affinity column. One of them is the wheat elongation factor 1A. Its putative regulatory role in DNA replication/repair is discussed.