363 What do cytokine polymorphisms tell us about human population history? The case of European populations

Abstracts / Cytokine 43 (2008) 326–332 Here, we present a novel and more complex mechanism for Gab1 translocation which involves and depends on the activation of ERK. This mechanism represents a new mode of regulation for the function of PH domains. doi:10.1016/j.cyto.2008.07.444

360 Cross-regulation of cytokine signalling: Pro-inflammatory cytokines restrict IL-6 signalling through receptor internalisation and degradation Simone Radtke 1, Xiang-ping Yang 1, Stefan Wüller 1, Matthias Gaestel 2, Peter C. Heinrich 1, Fred Schaper 1, , Heike M. Hermanns 1,3, , 1 Department of Biochemistry, Medical School RWTH Aachen, 52074 Aachen, Germany, 2 Department of Biochemistry, Medical School Hannover, 30625 Hannover, Germany, 3 Rudolf-Virchow-Center, DFG Research Center for Experimental Biomedicine, 97078 Wu¨rzburg, Germany The inflammatory response involves a complex interplay of different cytokines which act in an auto- or paracrine manner to induce the so-called acute phase response. In our study we discovered a new mechanism which answers the longstanding question how pro-inflammatory cytokines and environmental stress restrict immediate signalling of IL-6-type cytokines. We show that p38 activated by IL-1b, TNFa or environmental stress impairs IL-6-induced JAK/STAT signalling through phosphorylation of the common cytokine receptor subunit gp130 and its subsequent internalisation and degradation. We identify MK2 as the executing kinase to phosphorylate serine 782 in the cytoplasmic part of gp130. Consequently, inhibition of p38 or MK2, deletion of MK2 or mutation of crucial amino acids within the MK2-target site or the di-leucine internalisation motif blocks receptor depletion and restores STAT activation. Hence, a novel negative cross-talk mechanism for cytokine signalling is described, where cytokine receptor turnover is regulated in trans by pro-inflammatory cytokines and stress stimuli to coordinate the inflammatory response.  

Both authors contributed equally to this work.

doi:10.1016/j.cyto.2008.07.445

361 Characterization of the bovine Type I interferon locus Angela Walker, R. Michael Roberts, Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA The Type I interferons (IFN) have major roles in the innate immune response to viruses, a function that is believed to have led to rapid expansion in the number and complexity of their genes. The locus encompassing these genes has remained intact during its evolutionary history. A highly conserved synteny is observed in mouse and human in which it has so far been examined. Specifically, IFNB and IFNE define the limits of the locus, with all other Type I IFN except IFNK distributed between these two most ancient genes, suggesting that the locus has broadened as IFN duplicated and then evolved into distinct subfamilies. Here we provide the first comprehensive annotation of the Type I IFN locus in Bos taurus. The locus has undergone significant rearrangement and expansion in bovine compared to mouse and human, with the constituent genes separated into two sub-loci separated by a >700 kb region. The IFNW subfamily is greatly expanded compared to other species, comprising 24 potentially functional genes. Selective pressure analysis reveals the regulatory regions of the IFNW are diverging faster than the coding regions. IFNA and IFNB are also present in multiple copies with 13 IFNA and 6 IFNB in the current genome annotation. Interestingly, only three IFNT, which encode a ruminant-specific IFN secreted by the pre-implantation conceptus, are present in the assembly despite previous work predicting that a greater number of copies is likely to be found. The identification of a new Type I IFN subfamily of four members, one of which is a pseudogene, apparently derived from the IFNA lineage at least 83 million years ago is the most striking finding of this study. At least one member of this previously unidentified gene subfamily is expressed in virally challenged bovine kidney cells, suggesting that the genes are virally inducible. doi:10.1016/j.cyto.2008.07.446

362 WNTS as a new kind of cytokines Jing-pu Zhang, Bin Hong, Yuan Yang, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences, Beijing, China Discovery of new cytokines will make the cytokine family enlarged, and make the cytokine conception improved and modified. A common viewpoint has been recognized following accumulation and development of the scientific achievement, that

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some of important developmental factors have double roles as the two sides of a coin. They play crucial roles in directing embryonic development and differentiation, once they are disregulated in gene expression, embryo malformation and congenital disease will occur; on the other hand, in adults, the factors emerge currently accompanying serious diseases, such as cancers, inflammation, etc. Some reports showed that Wnt signals, which are important developmental signals in embryogenesis, were implicated in expression of pro-inflammatory cytokines (IL6, IL8, IL15) in lung inflammation and rheumatoid arthritis; also Wnt pathway participated in tumor formation, such as colonic neoplasia, breast cancer, colonic neoplasia, advanced cancer of the uterine cervix, colorectal and liver tumors. Moreover, these factors have features of cytokines, such as secreted proteins, multiple regulatory actions, network signal transduction between cytokines, and effect in chronergy. So, we propose Wnt family proteins as a new kind of cytokine. Firstly, we have cloned wnt8a cds from human and zebrafish cDNA libraries; utilizing zebrafish, have investigated wnt8a (a canonical wnt member) interaction with a novel zinc-finger protein zapx in embryonic development, and found that wnt8a over-expression resulted in zapx ectopic over-transcription at the embryonic ventral and lateral margins (where are the signal sources required for embryonic posterior and ventral fates) at 90% epiboly stage and led to ventralized embryos—the central nervous system was damaged seriously. Currently we are investigating wnt8a interaction with VEGF expression in some tumors, for example, colonic neoplasia and breast cancer, to reveal wnt8 contribution contributed to the tumor development in gene regulation at cell level. doi:10.1016/j.cyto.2008.07.447

363 What do cytokine polymorphisms tell us about human population history? The case of European populations Fabian A. Crespo 1,2, Rafael Fernandez-Botrán 3, Manuel F. Casanova 2, Rachel Oberst 4, Christopher R. Tillquist 1, 1 Department of Anthropology, University of Louisville, Louisville, KY 40292, USA, 2 Department of Psychiatry and Behavioral Sciences, University of Louisville, Louisville, KY 40292, USA, 3 Department of Pathology and Laboratory Medicine, University of Louisville, Louisville, KY 40292, USA, 4 Department of Biology, University of Louisville, Louisville, KY 40292, USA Many cytokines and their receptors are encoded by highly polymorphic genes, and some polymorphisms have been linked to specific ethnic groups or populations. These cytokine polymorphisms determine differential levels of systemic expression. Until today, only groups or individual populations with prevalent specific diseases have been studied. Studies scored polymorphisms for individual cytokines or a small non-regular set of cytokines, thus making difficult global and comparative analyses. We report results from a survey of common polymorphisms giving differential expression in TNFa, IFNc, IL-6, TGFb1, and IL-10 in 18 geographically distinct European populations. We combine previously published data for European populations with newly generated data. Analyses reveal that frequencies of certain genotypes for specific cytokines document a non-random distribution with significant regional variation. In some cases, the ancestral allele is maintained at high frequency, while in others there is an increased frequency of the derived allele when compared to other non-European populations. Specifically, there may be ongoing selective sweeps in IFNc, IL-6, TGFb1 codon 10, and IL10. In the case of pro-inflammatory cytokines, the most frequent allele of a given cytokine is the one contributing to lower expression, while in the case of anti-inflammatory cytokines the most frequent allele is the one giving higher expression. Demographic processes such as the initial colonization of Europe likely impacted current distributions: this we infer from the distributions and correlograms of the derived alleles of IL-6 and TGFb1 (10). Thus, the overall picture is one of maintaining the general shift to lower inflammation with an overlay of demography. doi:10.1016/j.cyto.2008.07.448

364 Single nucleotide polymorphisms of TNF-a gene and its receptors 1 and 2 in Mexican lepromatous leprosy patients Margarita Montoya-Buelna 1, José F. Muñoz-Valle 2, Anabell Alvarado-Navarro 3, Rocio I. López Roa 3, Luis E. Figuera-Villanueva 1, Mary Fafutis-Morris 3, 1 Centro de Investigacio´n Biome´dica de Occidente, Instituto Mexicano del Seguro Social, Mexico, 2 Instituto de Investigacio´n en Reumatologı´a y del Sistema Mu´sculo Esquele´tico, Universidad de Guadalajara, Mexico, 3 Centro de Investigacio´n en Inmunologı´a y Dermatologı´a, Universidad de Guadalajara, Mexico Leprosy is a chronic infectious disease caused by Mycobacterium leprae, where tumor necrosis factor-alpha (TNF-a) activates several effector mechanisms against this infection binding to its receptors (TNFR1 and TNFR2). The TNF-a promoter polymorphism at position—308 (named TNF2) has been extensively associated with a variety of autoimmune and infectious diseases, such as leprosy. In addition, polymorphic variants in both TNFR genes are associated with several disorders, although in