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Lenz J.,Johannes Gutenberg University Mainz | Lenz J.,Biodiversity and Climate Research Center | Fiedler W.,Max Planck Institute for Ornithology (Radolfzell) | Caprano T.,Johannes Gutenberg University Mainz | And 7 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2011

Frugivorous birds provide important ecosystem services by transporting seeds of fleshy fruited plants. It has been assumed that seed-dispersal kernels generated by these animals are generally leptokurtic, resulting in little dispersal among habitat fragments. However, little is known about the seed-dispersal distribution generated by large frugivorous birds in fragmented landscapes. We investigated movement and seed-dispersal patterns of trumpeter hornbills (Bycanistes bucinator) in a fragmented landscape in South Africa. Novel GPS loggers provide high-quality location data without bias against recording long-distance movements. We found a very weakly bimodal seed-dispersal distribution with potential dispersal distances up to 14.5 km. Within forest, the seed-dispersal distribution was un imodal with an expected dispersal distance of 86 m. In the fragmented agricultural landscape, the distribution was strongly bimodal with peaks at 18 and 512 m. Our results demonstrate that seed-dispersal distributions differed when birds moved in different habitat types. Seed-dispersal distances in fragmented landscapes show that transport among habitat patches is more frequent than previously assumed, allowing plants to disperse among habitat patches and to track the changing climatic conditions. © 2010 The Royal Society. Source


Lee J.,Texas A&M University | Banu S.K.,Texas A&M University | Burghardt R.C.,Texas A&M University | Starzinski-Powitz A.,Institute For Zellbiologie Und Neurowissenschaft | Arosh J.A.,Texas A&M University
Biology of Reproduction | Year: 2013

Endometriosis is a chronic gynecological disease of reproductive age women characterized by the presence of functional endometrial tissues outside the uterine cavity. Interactions between the endometriotic cells and the peritoneal extracellular matrix proteins (ECM) are crucial mechanisms that allow adhesion of the endometriotic cells into peritoneal mesothelia. Prostaglandin E2 (PGE2) plays an important role in the pathogenesis of endometriosis. In previous studies, we have reported that selective inhibition of PGE2 receptors PTGER2 and PTGER4 decreases survival and invasion of human endometriotic epithelial and stromal cells through multiple mechanisms. Results of the present study indicates that selective inhibition of PTGER2- and PTGER4-mediated PGE2 signaling 1) decreases the expression and/or activity of specific integrin receptor subunits Itgb1 (beta1) and Itgb3 (beta3) but not Itgb5 (beta5), Itga1 (alpha1), Itga2 (alpha2), Itga5 (alpha5), and Itgav (alphav); 2) decreases integrin-signaling components focal adhesion kinase or protein kinase 2 (PTK2) and talin proteins; 3) inhibits interactions between Itgb1/Itgb3 subunits, PTK2, and talin and PTGER2/PTGER4 proteins through beta-arrestin-1 and Src kinase protein complex in human endometriotic epithelial cells 12Z and stromal cells 22B; and 4) decreases adhesion of 12Z and 22B cells to ECM collagen I, collagen IV, fibronectin, and vitronectin in a substrate-specific manner. These novel findings provide an important molecular framework for further evaluation of selective inhibition of PTGER2 and PTGER4 as potential nonsteroidal therapy to expand the spectrum of currently available treatment options for endometriosis in child-bearing age women. © 2013 by the Society for the Study of Reproduction, Inc. Source


Arosh J.A.,Texas A&M University | Lee J.,Texas A&M University | Starzinski-Powitz A.,Institute For Zellbiologie Und Neurowissenschaft | Banu S.K.,Institute For Zellbiologie Und Neurowissenschaft
Molecular and Cellular Endocrinology | Year: 2015

Endometriosis is an inflammatory gynecological disease of reproductive-age women. The prevalence of endometriosis is 5-10% in reproductive-age women. Modern medical treatments are directed to inhibit the action of estrogen in endometriotic cells. However, hormonal therapies targeting estrogen can be prescribed only for a short time because of their undesirable side effects. Recent studies from our laboratory, using human endometriotic epithelial cell line 12Z and stromal cell line 22B derived from red lesion, discovered that selective inhibition of prostaglandin E2 (PGE2) receptors EP2 and EP4 inhibits adhesion, invasion, growth, and survival of 12Z and 22B cells by modulating integrins, MMPs and TIMPs, cell cycle, survival, and intrinsic apoptotic pathways, suggesting multiple epigenetic mechanisms. The novel findings of the present study indicate that selective pharmacological inhibition of EP2 and EP4: (i) decreases expression of DNMT3a, DNMT3b, H3K9me3, H3K27me3, SUV39H1, HP1a, H3K27, EZH2, JMJD2a, HDAC1, HDAC3, MeCP2, CoREST and Sin3A; (ii) increases expression of H3K4me3, H3H9ac, H3K27ac; and (iii) does not modulate the expression of DNMT1, hSET1, LSD1, MBD1, p300, HDAC2, and JMJD3 epigenetic machinery proteins in an epithelial and stromal cell specific manner. In this study, we report for the first time that inhibition of PGE2-EP2/EP4 signaling modulates DNA methylation, H3 histone methylation and acetylation, and epigenetic memory machinery proteins in human endometriotic epithelial cells and stromal cells. Thus, targeting EP2 and EP4 receptors may emerge as long-term nonsteroidal therapy for treatment of active endometriotic lesions in women. © 2015 Elsevier Ireland Ltd. Source

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