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Here we report on a partial skull and isolated horn core material of the boselaphin bovid Miotragocerus monacensis Stromer von Reichenbach, 1928 from the late Miocene hominid locality Hammerschmiede in southern Germany (HAM). The partial skull comprises the most complete cranial remains of M. monacensis so far. Using µCT analysis, we demonstrate the unique morphology of the basicranium of M. monacensis, compared to closely related boselaphin bovids like M. pannoniae Kretzoi, 1941, M. valenciennesi Gaudry, 1861 and Tragoportax rugosifrons Schlosser, 1904, all from the late Miocene. In addition, the µCT data of the cranium provide insight into the morphology of the cornual diverticulum (frontal sinus) supporting the presence of frontal sinuses within basal bovids. Besides the cranium, we describe further isolated horn core material from both the HAM 5 horizon (11.62?Ma) and for the first time the HAM 4 horizon (11.44?Ma), being the stratigraphic youngest record of this species.

Many ideas have been proposed to explain the origin of bipedalism in hominins and suspension in great apes (hominids); however, fossil evidence has been lacking. It has been suggested that bipedalism in hominins evolved from an ancestor that was a palmigrade quadruped (which would have moved similarly to living monkeys), or from a more suspensory quadruped (most similar to extant chimpanzees)1. Here we describe the fossil ape Danuvius guggenmosi(from the Allgäu region of Bavaria) for which complete limb bones are preserved, which provides evidence of a newly identified form of positional behaviour—extended limb clambering. The 11.62-million-year-old Danuviusis a great ape that is dentally most similar to Dryopithecusand other European late Miocene apes. With a broad thorax, long lumbar spine and extended hips and knees, as in bipeds, and elongated and fully extended forelimbs, as in all apes (hominoids), Danuviuscombines the adaptations of bipeds and suspensory apes, and provides a model for the common ancestor of great apes and humans.

Reversible histone acetylation changes the chromatin structure and can modulate gene transcription. Mammalian histone deacetylase 1 (HDAC1) is a nuclear protein that belongs to a growing family of evolutionarily conserved enzymes catalysing the removal of acetyl residues from core histones and other proteins. Previously, we have identified murine HDAC1 as a growth factor-inducible protein in murine T-cells. Here, we characterise the molecular function of mouse HDAC1 in more detail. Co-immunoprecipitation experiments with epitope-tagged HDAC1 protein reveal the association with endogenous HDAC1 enzyme. We show that HDAC1 can homo-oligomerise and that this interaction is dependent on the N-terminal HDAC association domain of the protein. Furthermore, the same HDAC1 domain is also necessary for in vitrobinding of HDAC2 and HDAC3, association with RbAp48 and for catalytic activity of the enzyme.

SDS3(suppressor of defective silencing 3) was originally identified in a screen for mutations that cause increased silencing of a crippled HMRsilencer in arap1mutant background. In addition, sds3mutants have phenotypes very similar to those seen in sin3and rpd3mutants, suggesting that it functions in the same genetic pathway. In this manuscript we demonstrate that Sds3p is an integral subunit of a previously identified high molecular weight Rpd3p·Sin3p containing yeast histone deacetylase complex. By analyzing an sds3Δ strain we show that, in the absence of Sds3p, Sin3p can be chromatographically separated from Rpd3p, indicating that Sds3p promotes the integrity of the complex. Moreover, the remaining Rpd3p complex in the sds3Δ strain had little or no histone deacetylase activity. Thus, Sds3p plays important roles in the integrity and catalytic activity of the Rpd3p·Sin3p complex.

Focuses on audit strategies for defending against proposed excess accumulated earnings tax assessment. Turnover ratios that the corporation must calculate under the Bardahl formula used by the United States International Revenue Service; Commencement of audit procedures; Approaches that taxpayers can use to assist in disputing an accumulated earnings tax assessment.

Specific lysine residues in the N-terminal extensions of core histones can be posttranslationally modified by acetylation of the ϵ-amino group. The dynamic equilibrium of core histone acetylation is established and maintained by histone acetyltransferases and deacetylases. Both enzymes exist as multiple enzyme forms. Histone acetyltransferases and deacetylases have recently been identified as transcriptional regulators as well as nucleolar phosphoproteins, and have therefore attracted considerable research interest. Analysis of the functional significance of histone deacetylases for nuclear processes in certain cases demands the separation and biochemical analysis of different members of the histone deacetylase families. We have characterized three different histones deacetylases in maize embryos and subsequently purified these enzymes to homogeneity. Here we describe methods for extraction, enzymatic assay, chromatographic and electrophoretic separation, and purification of deacetylases. A novel one-step procedure for large-scale preparation of individual histones and their acetylated isoforms for the analysis of substrate and site specificity of the enzymes is presented.

From a soluble cellular fraction of maize embryos we purified to apparent homogeneity a cytoplasmic histone acetyltransferase, which matches all criteria for a B‐type enzyme. Using 8 chromatographic steps, we achieved a 6700‐fold purification of an enzymatically active protein with a molecular weight of ∼ 90 kDa. Under denaturing conditions the protein split into 2 components which migrated at 45 and 50 kDa in SDS‐PAGE, suggesting that the native enzyme is a heterodimer. The purified enzyme was characterized in terms of physicochemical and kinetic properties, and substrate specificity. It was specific for histone H4, leading to acetylation of non‐acetylated H4 subspecies into the di‐acetylated state in vitro. Its activity was coincident with the intensity of DNA replication in meristematic cells during embryo germination. We established an electrophoretic system under non‐denaturing conditions for detection of enzyme activity within the gel matrix; in combination with second dimension SDS‐PAGE the procedure allowed the unambiguous identification of histone acetyltransferase, even in crude enzyme preparations.

To maintain the integrity of the Vasawarship after salvage in 1961, conservation treatment with polyethylene glycol was carried out to prevent the collapse of cell walls. This treatment had negative effects on the strength and stiffness of the oak and the hull structure has been found to slowly deform over time. It is of interest to construct a three-dimensional numerical computer model to model and predict the deformation of the warship. This creates difficulties related to the complexity of measuring the detailed material properties that are required as input. In this context, a non-destructive methodology to predict the stiffness of the Vasaoak in terms of moduli of elasticity in the three principal directions of timber at critical positions in the ship would be useful. The twofold aim of the paper is to propose a strategy for a support system and to conduct an on-site assessment of the warship to predict the mechanical properties of the Vasaoak material. This paper also contains an up-to-date review of all essential mechanical data measured on the Vasaoak. The preliminary investigation using an X-ray technique to investigate the density properties produced promising results for future use in the evaluation of the mechanical performance. Based on these results, a procedure to establish the stiffness properties of the Vasaoak in terms of MOE was suggested, using a combination of data from previous measurements, in combination with extended tests on Vasaoak specimens and an X-ray-based density calibration procedure. The general complexity of the Vasawarship can be mainly attributed to large variations in the properties of Vasaoak due to surface degradation, chemical treatment and the disintegration of the cell-wall structure originating from centuries of waterlogged conditions. That causes difficulties when assessing mechanical and physical properties on a structural level. A combination of visual inspection together with X-ray investigation is of great importance to evaluate those properties and to obtain more accurate estimates. The results from evaluating mechanical properties can serve as input in a numerical model and serve as a foundation for decision-making relating to the modification of the support system.