Molecular footprints of human immunoglobulin gene evolution: a new sequence family.

Analysis of the human VK (ref. 2) gene locus led to the detection of a new sequence family (L sequences). Its copy number is in the range of 10(2). The L sequences, which are about 500 bp long, are found as part of the 3' flanking regions of a clustered set of human VKI genes but they occur also separate from the genes. Models are discussed in which L sequences are viewed as molecular footprints of amplification and transposition processes of VK genes

Deciphering the regulatory logic of a Drosophila enhancer through systematic sequence mutagenesis and quantitative image analysis

Transcriptional enhancers are short DNA sequences controlling the spatial activity, timing and levels of eukaryotic gene transcription. Their quantitative transcriptional output is thought to result from the number and organization of transcription factor binding sites (TFBSs). Yet, how the various aspects of regulatory information are encoded in enhancer sequences remains elusive. We addressed this question by quantifying the spatial activity of the yellow spot enhancer active in developing Drosophila wings. To identify which enhancer DNA sequence contributes to enhancer activity, we introduced systematic mutations along the enhancer. We developed an analytic framework that uses comprehensive descriptors to quantify reporter assay in transgenic flies and measure spatial variations in activity levels across the wing. Our analysis highlights an unexpected density of regulatory information in the spot enhancer sequence. Furthermore, it reveals an unanticipated regulatory logic underlying the activity of this enhancer, and how it reads the wing trans-regulatory landscape to encode a spatial pattern

The Fair Trade Idea: Towards an Economics of Social Labels

The concept of Fair Trade is applied to the marketing of a variety of goods. In recent years it has met a continually increasing interest among consumers. Different Fair Trade organizations are trying to accomplish an improvement in working and living conditions in developing countries by means of Fair Trade certificates and by paying a price markedly above world market standard. This is meant to lead to the attainment of basic social standards, especially in agricultural production. The article deals with how Fair Trade works and whether the social aims can be achieved by the application of this trade concept. Our main result is that even though efficiency of redistribution through the Fair Trade institutions is lower than through traditional relief organizations, the Fair Trade concept provides an additional incentive to support better living conditions in the Third World. Moreover, it provides a stimulus for producers to reorganize the production process in a socially more acceptable manner even when this is not rewarded by the Fair Trade company. Copyright Springer Science+Business Media, LLC 2007Fair trade, Social labels, International trade, Sustainability, Social justice, Extrinsic product quality,