Role of the Polymerase ϵ sub-unit DPB2 in DNA replication, cell cycle regulation and DNA damage response in Arabidopsis

Faithful DNA replication maintains genome stability in dividing cells and from one generation to the next. This is particularly important in plants because the whole plant body and reproductive cells originate from meristematic cells that retain their proliferative capacity throughout the life cycle of the organism. DNA replication involves large sets of proteins whose activity is strictly regulated, and is tightly linked to the DNA damage response to detect and respond to replication errors or defects. Central to this interconnection is the replicative polymerase DNA Polymerase ϵ (Pol ϵ) which participates in DNA replication per se, as well as replication stress response in animals and in yeast. Surprisingly, its function has to date been little explored in plants, and notably its relationship with DNA Damage Response (DDR) has not been investigated. Here, we have studied the role of the largest regulatory sub-unit of Arabidopsis DNA Pol ϵ DPB2, using an over-expression strategy. We demonstrate that excess accumulation of the protein impairs DNA replication and causes endogenous DNA stress. Furthermore, we show that Pol ϵ dysfunction has contrasting outcomes in vegetative and reproductive cells and leads to the activation of distinct DDR pathways in the two cell types. © 2016 The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research

Austrian Debates on Utility Measurement from Menger to Hayek

This paper examines how some of the main exponents of the Austrian school of economics addressed the issues related to the measurability of utility. The first part is devoted to the period before World War I. During this period, Menger and Wieser treated de facto utilities as if they were measurable and could be expressed as multiples of a utility unit, B\uf6hm-Bawerk and the young Schumpeter defended explicitly the measurability of utility, while, in contrast to these views, \u10cuhel and Mises argued that utilities cannot be measured but only ranked. After World War I, the ordinal view became the dominant one among Austrian economists but they admitted that individuals are not only able to rank the utility of goods (as in the ordinal approach), but are also capable of ranking differences of utility. The second part of the paper reconstructs the interwar discussions on the ranking of utility differences, focusing on the contributions of Sch\uf6nfeld, Rosenstein-Rodan, Morgenstern and Alt. The paper concludes by illustrating Hayek\u2019s ordinal view of utility