Genetic analysis of the human tumor necrosis factor alpha/cachectin promoter region in a macrophage cell line.

The 615-bp 5' flanking region of the human TNF-alpha/cachectin gene was isolated and ligated to the luciferase reporter gene. In addition, a series of truncated promoter constructs was generated by exonuclease III digestion. The promoter activity of these constructs was studied in a transient transfection system using the TNF-alpha-producing U937 cell line. Full-length and truncated TNF promoter constructions extending from -615 to -95 bp relative to the transcription start site (TSS) could be induced by phorbol esters. A construct truncated to within 36 bp of the TSS (and within 11 bp of the TATAA box) was inactive. Therefore, the phorbol ester responsive is localized in the TNF/cachectin promoter to a relatively short region proximal to the TATAA box

Regulation of Gut and Heart Left–Right Asymmetry by Context-Dependent Interactions between Xenopus Lefty and BMP4 Signaling

AbstractThe Lefty subfamily of TGFβ signaling molecules has been implicated in early development in mouse, zebrafish, and chick. Here, we show that Xenopus lefty (Xlefty) is expressed both bilaterally in symmetric midline domains and unilaterally in left lateral plate mesoderm and anterior dorsal endoderm. To examine the roles of Xlefty in left–right development, we created a system for scoring gut asymmetry and examined the effects of unilateral Xlefty misexpression on gut development, heart development, and Xnr-1 and XPitx2 expression. In contrast to the unilateral effects of Vg1, Activin, Nodal, or BMPs, targeted expression of Xlefty in either the left or the right side of Xenopus embryos randomized the direction of heart looping, gut coiling, and left–right positioning of the gut and downregulated the asymmetric expression of Xnr-1 and XPitx2. It is currently thought that Lefty proteins act as feedback inhibitors of Nodal signaling. However, this would not explain the effects of right-sided Xlefty misexpression. Here, we show that Xlefty interacts with the signaling pathways of other members of the TGFβ family during left–right development. Results from coexpression of Xlefty and Vg1 indicate that Xlefty can nullify the effects of Vg1 ectopic expression and that Xlefty is downstream of left-sided Vg1 signaling. Results from coexpression of Xlefty and XBMP4 indicate that XLefty and XBMP4 interact both synergistically and antagonistically in a context-dependent manner. We propose a model in which interactions of Xlefty with multiple members of the TGFβ family enhance the differences between the right-sided BMP/ALK2/Smad pathway and the left-sided Vg1/anti-BMP/Nodal pathway, leading to left–right morphogenesis of the gut and heart

Multiple Roles of Pitx2 in Cardiac Development and Disease

Cardiac development is a complex morphogenetic process initiated as bilateral cardiogenic mesoderm is specified at both sides of the gastrulating embryo. Soon thereafter, these cardiogenic cells fuse at the embryonic midline configuring a symmetrical linear cardiac tube. Left/right bilateral asymmetry is first detected in the forming heart as the cardiac tube bends to the right, and subsequently, atrial and ventricular chambers develop. Molecular signals emanating from the node confer distinct left/right signalling pathways that ultimately lead to activation of the homeobox transcription factor Pitx2 in the left side of distinct embryonic organ anlagen, including the developing heart. Asymmetric expression of Pitx2 has therefore been reported during different cardiac developmental stages, and genetic deletion of Pitx2 provided evidence of key regulatory roles of this transcription factor during cardiogenesis and thus congenital heart diseases. More recently, impaired Pitx2 function has also been linked to arrhythmogenic processes, providing novel roles in the adult heart. In this manuscript, we provide a state-of-the-art review of the fundamental roles of Pitx2 during cardiogenesis, arrhythmogenesis and its contribution to congenital heart diseases

Spring 2021: Junior Girls

https://griffinshare.fontbonne.edu/fas-205-projects/1010/thumbnail.jp

Basal body stability and ciliogenesis requires the conserved component Poc1

Centrioles are the foundation for centrosome and cilia formation. The biogenesis of centrioles is initiated by an assembly mechanism that first synthesizes the ninefold symmetrical cartwheel and subsequently leads to a stable cylindrical microtubule scaffold that is capable of withstanding microtubule-based forces generated by centrosomes and cilia. We report that the conserved WD40 repeat domain–containing cartwheel protein Poc1 is required for the structural maintenance of centrioles in Tetrahymena thermophila. Furthermore, human Poc1B is required for primary ciliogenesis, and in zebrafish, DrPoc1B knockdown causes ciliary defects and morphological phenotypes consistent with human ciliopathies. T. thermophila Poc1 exhibits a protein incorporation profile commonly associated with structural centriole components in which the majority of Poc1 is stably incorporated during new centriole assembly. A second dynamic population assembles throughout the cell cycle. Our experiments identify novel roles for Poc1 in centriole stability and ciliogenesis

The morphology of UHMWPE wear debris generated by a hip joint simulator

The size, quantity and shape of total hip replacement wear debris may identify wear mechanisms as well as play a role in osteolysis. Characterization of wear particles generated from a hip joint simulator was conducted followed by comparison with literature reported in vivo results. The effect of counterface material and lubricant type on particle morphology was assessed. Biomaterial pairs including UHMWPE articulated against CoCr, Alumina and Zirconia were considered. Deionized (D.I.) water and bovine serum were used as lubricants. Particles generated from Alumina/UHMWPE in serum were slightly larger than those for CoCr and Zirconia against UHMWPE in serum. Particle shape for these materials in serum were similar, with two types including a round or egg shaped submicron one and an elongated fibrous 1-2 micron one. Particles from CoCr against UHMWPE in D.I. water were flake like in shape and in the millimeter size range with some in the 5 micron range as well. The water condition produced particles dissimilar to the others. Literature reported clinical findings supported the particle types and sizes generated under serum while those generated in water were not supported in the literature. The in vitro simulator was found to accurately reproduce in vivo wear mechanisms under serum lubrication based on debris characterization results

Sixth Amendment; Right to Counsel; Multiple Representation; Cuyler v. Sullivan

In Cuyler v. Sullivan, the Supreme Court finally resolved two important issues in the areas of criminal law and the sixth amendment right to counsel. In this case, the Court is faced with a situation with which it has dealt but twice before: joint representation of criminal defendants. Cuyler represents the culmination of the legal inquiry into the problems inherent whenever a single attorney represents more than one defendant in a criminal proceeding

Municipal Annexation in Ohio

The adoption of aggressive municipal annexation programs by many cities in Ohio has often resulted in controversy. This is especially true in the City of Akron where recent attempts to annex large sections of neighboring townships have met with strong resistance from residents. The animosity created by this issue has made cooperation between the city and the townships virtually impossible, resulting in both an ineffective government and an inefficient use of resources. To resolve this conflict, the parties have engaged in protracted legal battles which test recent statutory changes in the law of annexation in Ohio. The outcome of these cases may lead to significant developments in the legal arsenal of annexation opponents. This comment will examine policy considerations both supporting and opposing annexation as well as the statutory scheme for annexation in Ohio, placing special emphasis on recent court tests