Analysis of Heterokaryon Formation in Fusarium oxysporum f. sp. cubense.

Fusarium oxysporum forma specialis cubense is a soilborne phytopathogen that infects banana. The true evolutionary identity of this so called species, Fusarium oxysporum, is still unknown. Many techniques have been applied in order to gain insight for the observed genetic diversity of this species. The current classification system is based on vegetative compatibility groups (VCG's). Vegetative compatibility is a self non-self recognition system in which only those belonging to a VCG can form stable heterokaryons, cells containing two distinct nuclei. Heterokaryons in turn, are formed from hypha! anastomosis, the fusion of two hyphae. Furthermore, subsequent to heterokaryon formation potential mechanisms exist which may generate genetic variability. One is through viral transfer upon hyphal anastomosis. The other mechanism is a form of mitotic recombination referred to as the parasexual cycle. Very little research has been performed to directly obser.ve the cellular events; hypha! anastomosis, heterokaryon formation, and the parasexual cycle in Fusarium oxysporum f. sp. cubense. The purpose of this research was to design and use methods which would allow for the detection of hypha! anastomosis and heterokaryon formation, as well as any characteristics surrounding this event, within and between VCG's in Foe. First, some general growth properties were recorded: the number of nuclei per hypha, the size ofthe hyphal tip cell, the size of the cell adjacent to the hypha! tip (pre-tip) cell, and the number of cells to the first branch point. Second, four methods were designed in order to assay hyphal anastomosis and heterokaryon formation: 1) pairings on membrane: phase or brightfield microscopy, 2) pairings on membrane: fluorescence microscopy, 3) spore crosses: fluorescence microscopy, and 4) double picks in fractionated MMA. All of these methods were promtsmg.

Integrated Carbon Budget Models for the Everglades Terrestrial-Coastal-Oceanic Gradient: Current Status and Needs for Inter-Site Comparisons

Recent studies suggest that coastal ecosystems can bury significantly more C than tropical forests, indicating that continued coastal development and exposure to sea level rise and storms will have global biogeochemical consequences. The Florida Coastal Everglades Long Term Ecological Research (FCE LTER) site provides an excellent subtropical system for examining carbon (C) balance because of its exposure to historical changes in freshwater distribution and sea level rise and its history of significant long-term carbon-cycling studies. FCE LTER scientists used net ecosystem C balance and net ecosystem exchange data to estimate C budgets for riverine mangrove, freshwater marsh, and seagrass meadows, providing insights into the magnitude of C accumulation and lateral aquatic C transport. Rates of net C production in the riverine mangrove forest exceeded those reported for many tropical systems, including terrestrial forests, but there are considerable uncertainties around those estimates due to the high potential for gain and loss of C through aquatic fluxes. C production was approximately balanced between gain and loss in Everglades marshes; however, the contribution of periphyton increases uncertainty in these estimates. Moreover, while the approaches used for these initial estimates were informative, a resolved approach for addressing areas of uncertainty is critically needed for coastal wetland ecosystems. Once resolved, these C balance estimates, in conjunction with an understanding of drivers and key ecosystem feedbacks, can inform cross-system studies of ecosystem response to long-term changes in climate, hydrologic management, and other land use along coastlines.

Thalidomide and birth defects

Apologies to the many papers we were unable to cite, due to space constraints. We thank Lynda Erskine, Shaunna Beedie and Chris Mahony for helpful discussions. Lucas Rosa Fraga is funded by a PhD scholarship from the Science without Borders program - CNPq Brazil - INAGEMP/ Grant CNPq 573993/2008-4. Alex J. Diamond is funded by a BBSRC DTP PhD Scholarship.

Thalidomide and birth defects

Apologies to the many papers we were unable to cite, due to space constraints. We thank Lynda Erskine, Shaunna Beedie and Chris Mahony for helpful discussions. Lucas Rosa Fraga is funded by a PhD scholarship from the Science without Borders program - CNPq Brazil - INAGEMP/ Grant CNPq 573993/2008-4. Alex J. Diamond is funded by a BBSRC DTP PhD Scholarship.

Yes-associated protein (YAP) is a negative regulator of chondrogenesis in mesenchymal stem cells

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Acknowledgements The authors would like to thank Dr Marius Sudol for the hYAP plasmids (obtained through Addgene), Dr Pete Zammit for the pMSCV-IRES-eGFP plasmid, Dr Robert Judson for subcloning the hYAP cDNAs into the pMSCV-IRES-eGFP plasmid, Dr Lynda Erskine for the provision of mouse embryo samples, and Professor Jimmy Hutchison and the Orthopaedics Department at the Aberdeen Royal Infirmary for the provision of human tissue samples. The authors are also grateful to Denise Tosh and Susan Clark for excellent technical support. This work was funded by Arthritis Research UK (grant 19429).

Common Bound: The Small Groups of Methodism

The system of small groups John Wesley established to promote a proper life of discipleship in early Methodist converts was, in many respects, the strength of the Methodist movement. Those who responded to Wesley’s initial invitation to “flee the wrath to come” were organized into large gatherings called “societies,” which were then subdivided into smaller bands, class meetings, select societies, and penitent bands. The smaller groups gave Wesley the opportunity, through a system of appointed leaders, to keep track of the spiritual progress of every member in his movement, which grew to tens of thousands by the time of his death in 1791. As Methodism shifted from renewal movement to institutional church in the nineteenth century, however, growth slowed, and participation in such groups declined rapidly. By the early twentieth century, classes and bands were virtually extinct in every sector of Methodism save the African-American tradition. In recent years, scholars in various sectors of the Wesleyan tradition, particularly David Lowes Watson and Kevin Watson, have called for a recovery of these small groups for purposes of renewal in the church. There is no consensus, however, concerning what exactly contributed to the vitality of these groups during Wesley’s ministry.

Over the last century, sociological studies of group dynamics have revealed three common traits that are crucial to highly functioning groups: interdependence created by the existence of a common goal, interaction among group members that is “promotive” or cooperative in nature, and high levels of feedback associated with personal responsibility and individual accountability. All three of these were prevalent in the early Methodist groups. Interdependence existed around a shared goal, which for Wesley and the Methodists was holiness. That interdependence was cooperative in nature; individuals experienced the empowering grace of God as they each pursued the goal in the company of fellow pilgrims. Finally, the groups existed for purposes of feedback and accountability as individuals took responsibility both for themselves and others as they progressed together toward the goal of holy living. Wesley seemed to instinctively understand the essential nature of each of these characteristics in maintaining the vitality of the movement when he spoke of the importance of preserving the “doctrine, spirit and discipline” of early Methodism. Analysis of some of the present-day attempts to restore Wesley’s groups reveals frequent neglect to one or more of these three components. Perhaps most critical to recovering the vitality of the early Methodist groups will be reclaiming the goal of sanctification and coming to a consensus on what its pursuit means in the present day.

Measuring sawgrass in macrophyte plots at TS/Ph-1 (Gustavo Rubio, Damon Rondeau)

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.