Catalytically Inactive Protein Phosphatase 2A Can Bind to Polyomavirus Middle Tumor Antigen and Support Complex Formation with pp60c-src

Interaction between the heterodimeric form of protein phosphatase 2A (PP2A) and polyomavirus middle T antigen (MT) is required for the subsequent assembly of a transformation-competent MT complex. To investigate the role of PP2A catalytic activity in MT complex formation, we undertook a mutational analysis of the PP2A 36-kDa catalytic C subunit. Several residues likely to be involved in the dephosphorylation mechanism were identified and mutated. The resultant catalytically inactive C subunit mutants were then analyzed for their ability to associate with a cellular (B subunit) or a viral (MT) B-type subunit. Strikingly, while all of the inactive mutants were severely impaired in their interaction with B subunit, most of these mutants formed complexes with polyomavirus MT. These findings indicate a potential role for these catalytically important residues in complex formation with cellular B subunit, but not in complex formation with MT. Transformation-competent MT is known to associate with, and modulate the activity of, several cellular proteins, including pp60(c-src) family kinases. To determine whether association of MT with an active PP2A A-C heterodimer is necessary for subsequent association with pp60(c-src), catalytically inactive C subunits were examined for their ability to form complexes containing pp60(c-src) in MT-expressing cells. Two catalytically inactive C subunit mutants that efficiently formed complexes with MT also formed complexes that included an active pp60(c-src) kinase, demonstrating that PP2A activity is not essential in cis in MT complexes for subsequent pp60(c-src) association.     

Familial occurrence of adrenocortical insufficiency in two brothers with Allgrove syndrome. A case report of 4A (Allgrove) syndrome with epilepsy and a new AAAS gene mutation

Allgrove syndrome is a rare autosomal recessive disease with achalasia, alacrima, adrenocortical insufficiency, autonomic neuropathy and other neurological disturbances. A case of two brothers with Addison s disease from early childhood is presented. The younger brother with Addison disease died at the age of 5. The older brother was treated for adrenocortical insufficiency from the age 3, and then treated for achalasia and epilepsy from the age of 5. The patient is currently 26 years old and suffers from achalasia and adrenocortical insufficiency. He also suffers from alacrima, autonomic neuropathy, epilepsy and other damages of the central and peripheral nervous system. The clinical picture is typical for Allgrove or 4A syndrome, and the diagnosis was confirmed by means of molecular analysis of a new AAAS gene mutation.     

Mapping brains without coordinates

Brain mapping has evolved considerably over the last century. While most emphasis has been placed on coordinate-based spatial atlases, coordinate-independent parcellation-based mapping is an important technique for accessing the multitude of structural and functional data that have been reported from invasive experiments, and provides for flexible and efficient representations of information. Here. we provide an introduction to motivations, concepts, techniques and implications of coordinate-independent mapping of microstructurally or functionally defined brain structures. In particular, we explain the problems of constructing mapping paths and finding adequate heuristics for their evaluation. We then introduce the three auxiliary concepts of acronym-based mapping (AM), of a generalized hierarchy (GM ontology), and of a topographically oriented regional map (RM) with adequate granularity for mapping between individual brains with different cortical folding and between humans and non-human primates. Examples from the CoCoMac database of primate brain connectivity demonstrate how these concepts enhance coordinate-independent mapping based on published relational statements. Finally, we discuss the strengths and weaknesses of spatial coordinate-based versus coordinate-independent microstructural brain mapping and show perspectives for a wider application of parcellation-based approaches in the integration of multi-model structural, functional, and clinical data.     

3D Bite Modeling and Feeding Mechanics of the Largest Living Amphibian,the Chinese Giant Salamander Andrias davidianus (Amphibia:Urodela)

Biting is an integral feature of the feeding mechanism for aquatic and terrestrial salamanders to capture, fix or immobilize elusive or struggling prey. However, little information is available on how it works and the functional implications of this biting system in amphibians although such approaches might be essential to understand feeding systems performed by early tetrapods. Herein, the skull biomechanics of the Chinese giant salamander, Andrias davidianus is investigated using 3D finite element analysis. The results reveal that the prey contact position is crucial for the structural performance of the skull, which is probably related to the lack of a bony bridge between the posterior end of the maxilla and the anterior quadrato-squamosal region. Giant salamanders perform asymmetrical strikes. These strikes are unusual and specialized behavior but might indeed be beneficial in such sit-and-wait or ambush-predators to capture laterally approaching prey. However, once captured by an asymmetrical strike, large, elusive and struggling prey have to be brought to the anterior jaw region to be subdued by a strong bite. Given their basal position within extant salamanders and their “conservative” morphology, cryptobranchids may be useful models to reconstruct the feeding ecology and biomechanics of different members of early tetrapods and amphibians, with similar osteological and myological constraints.     

A fish that uses its hydrodynamic tongue to feed on land

To capture and swallow food on land, a sticky tongue supported by the hyoid and gill arch skeleton has evolved in land vertebrates from aquatic ancestors that used mouth-cavity-expanding actions of the hyoid to suck food into the mouth. However, the evolutionary pathway bridging this drastic shift in feeding mechanism and associated hyoid motions remains unknown. Modern fish that feed on land may help to unravel the physical constraints and biomechanical solutions that led to terrestrialization of fish-feeding systems. Here, we show that the mudskipper emerges onto land with its mouth cavity filled with water, which it uses as a protruding and retracting ‘hydrodynamic tongue’ during the initial capture and subsequent intra-oral transport of food. Our analyses link this hydrodynamic action of the intra-oral water to a sequence of compressive and expansive cranial motions that diverge from the general pattern known for suction feeding in fishes. However, the hyoid motion pattern showed a remarkable resemblance to newts during tongue prehension. Consequently, although alternative scenarios cannot be excluded, hydrodynamic tongue usage may be a transitional step onto which the evolution of adhesive mucosa and intrinsic lingual muscles can be added to gain further independence from water for terrestrial foraging.     

Environmental life cycle assessment of yellow mealworm (Tenebrio molitor) production for human consumption in Austria – a comparison of mealworm and broiler as protein source

The International Journal of Life Cycle Assessment - Global food production needs to increase to provide enough food for over 9 billion people living by 2050. Traditional animal production is among...     

Odor-evoked autobiographical memories: age and gender differences along the life span

Odors are powerful in bringing back old and vivid memories bearing emotional content. This inherent hedonic property of olfactory stimuli makes this sensory modality particularly suitable for studying autobiographical memory. In the present work, adolescents (first experiment), young adults (second experiment), and elderly (third experiment) of both sexes were asked to smell 10 familiar odorants and to report if these odorants evoked personal autobiographical memories or referential memories (i.e., names and objects). The participants were then required to link these memories to triplets of words using the progressive elaboration method of the Loci mnemonic. The aim of the study was to investigate whether 1) odorants evoking autobiographical memories led to faster reaction times (RTs) and to a greater number of correct responses in the recall of the items associated to such memories than do odorants evoking referential memories, 2) females differed from males on the above tasks along with the life span, and 3) the preferential codes (i.e., autobiographical or referential) attributed to the odorants vary according to gender and age. In general, it was observed that the way in which the odorants were encoded affected the subsequent retrieval. Indeed, data analyses have shown that odorants evoking autobiographical memories lead to faster RTs (experiments 2 and 3) and that females outperform males (experiments 1 and 2). However, these effects are greatly age and gender dependent. Furthermore, females are more prone than males to code the odorants autobiographically (as shown by the higher amount of autobiographical experiences that they have provided at all ages relative to males). Results are discussed in terms of developmental differences and odor-emotion links and the possible role of odors and autobiographical memory in learning and retrieval of other items.