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31.
Mice and rats emit and perceive calls in the ultrasonic range, i.e., above the human hearing threshold of about 20 kHz: so-called ultrasonic vocalizations (USV). Juvenile and adult rats emit 22-kHz USV in aversive situations, such as predator exposure and fighting or during drug withdrawal, whereas 50-kHz USV occur in appetitive situations, such as rough-and-tumble play and mating or in response to drugs of abuse, e.g., amphetamine. Aversive 22-kHz USV and appetitive 50-kHz USV serve distinct communicative functions. Whereas 22-kHz USV induce freezing behavior in the receiver, 50-kHz USV lead to social approach behavior. These opposite behavioral responses are paralleled by distinct patterns of brain activation. Freezing behavior in response to 22-kHz USV is paralleled by increased neuronal activity in brain areas regulating fear and anxiety, such as the amygdala and periaqueductal gray, whereas social approach behavior elicited by 50-kHz USV is accompanied by reduced activity levels in the amygdala but enhanced activity in the nucleus accumbens, a brain area implicated in reward processing. These opposing behavioral responses, together with distinct patterns of brain activation, particularly the bidirectional tonic activation or deactivation of the amygdala elicited by 22-kHz and 50-kHz USV, respectively, concur with a wealth of behavioral and neuroimaging studies in humans involving emotionally salient stimuli, such as fearful and happy facial expressions. Affective ultrasonic communication therefore offers a translational tool for studying the neurobiology underlying socio-affective communication. This is particularly relevant for rodent models of neurodevelopmental disorders characterized by social and communication deficits, such as autism and schizophrenia. 相似文献
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The cranial and hyobranchial muscles of the Triassic temnospondyl Gerrothorax have been reconstructed based on direct evidence (spatial limitations, ossified muscle insertion sites on skull, mandible, and hyobranchium) and on phylogenetic reasoning (with extant basal actinopterygians and caudates as bracketing taxa). The skeletal and soft‐anatomical data allow the reconstruction of the feeding strike of this bottom‐dwelling, aquatic temnospondyl. The orientation of the muscle scars on the postglenoid area of the mandible indicates that the depressor mandibulae was indeed used for lowering the mandible and not to raise the skull as supposed previously and implies that the skull including the mandible must have been lifted off the ground during prey capture. It can thus be assumed that Gerrothorax raised the head toward the prey with the jaws still closed. Analogous to the bracketing taxa, subsequent mouth opening was caused by action of the strong epaxial muscles (further elevation of the head) and the depressor mandibulae and rectus cervicis (lowering of the mandible). During mouth opening, the action of the rectus cervicis muscle also rotated the hyobranchial apparatus ventrally and caudally, thus expanding the buccal cavity and causing the inflow of water with the prey through the mouth opening. The strongly developed depressor mandibulae and rectus cervicis, and the well ossified, large quadrate‐articular joint suggest that this action occurred rapidly and that powerful suction was generated. Also, the jaw adductors were well developed and enabled a rapid mouth closure. In contrast to extant caudate larvae and most extant actinopterygians (teleosts), no cranial kinesis was possible in the Gerrothorax skull, and therefore suction feeding was not as elaborate as in these extant forms. This reconstruction may guide future studies of feeding in extinct aquatic tetrapods with ossified hyobranchial apparatus. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc. 相似文献
33.
Xuexin Zhang José C. González-Cobos Rainer Schindl Martin Muik Brian Ruhle Rajender K. Motiani Jonathan M. Bisaillon Wei Zhang Marc Fahrner Margarida Barroso Khalid Matrougui Christoph Romanin Mohamed Trebak 《Molecular and cellular biology》2013,33(18):3715-3723
We recently showed, in primary vascular smooth muscle cells (VSMCs), that the platelet-derived growth factor activates canonical store-operated Ca2+ entry and Ca2+ release-activated Ca2+ currents encoded by Orai1 and STIM1 genes. However, thrombin activates store-independent Ca2+ selective channels contributed by both Orai3 and Orai1. These store-independent Orai3/Orai1 channels are gated by cytosolic leukotriene C4 (LTC4) and require STIM1 downstream LTC4 action. However, the source of LTC4 and the signaling mechanisms of STIM1 in the activation of this LTC4-regulated Ca2+ (LRC) channel are unknown. Here, we show that upon thrombin stimulation, LTC4 is produced through the sequential activities of phospholipase C, diacylglycerol lipase, 5-lipo-oxygenease, and leukotriene C4 synthase. We show that the endoplasmic reticulum-resident STIM1 is necessary and sufficient for LRC channel activation by thrombin. STIM1 does not form sustained puncta and does not colocalize with Orai1 either under basal conditions or in response to thrombin. However, STIM1 is precoupled to Orai3 and Orai3/Orai1 channels under basal conditions as shown using Forster resonance energy transfer (FRET) imaging. The second coiled-coil domain of STIM1 is required for coupling to either Orai3 or Orai3/Orai1 channels and for LRC channel activation. We conclude that STIM1 employs distinct mechanisms in the activation of store-dependent and store-independent Ca2+ entry pathways. 相似文献
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Chanjuan Guo Michael Dannenmann Rainer Gasche Bernd Zeller Hans Papen Andrea Polle Heinz Rennenberg Judy Simon 《Plant and Soil》2013,368(1-2):519-534
Background and aims
Litter decomposition is regulated by e.g. substrate quality and environmental factors, particularly water availability. The partitioning of nutrients released from litter between vegetation and soil microorganisms may, therefore, be affected by changing climate. This study aimed to elucidate the impact of litter type and drought on the fate of litter-derived N in beech seedlings and soil microbes.Methods
We quantified 15N recovery rates in plant and soil N pools by adding 15N-labelled leaf and/or root litter under controlled conditions.Results
Root litter was favoured over leaf litter for N acquisition by beech seedlings and soil microorganisms. Drought reduced 15N recovery from litter in seedlings thereby affecting root N nutrition. 15N accumulated in seedlings in different sinks depending on litter type.Conclusions
Root turnover appears to influence (a) N availability in the soil for plants and soil microbes and (b) N acquisition and retention despite a presumably extremely dynamic turnover of microbial biomass. Compared to soil microorganisms, beech seedlings represent a very minor short-term N sink, despite a potentially high N residence time. Furthermore, soil microbes constitute a significant N pool that can be released in the long term and, thus, may become available for N nutrition of plants. 相似文献38.
Hans‐Dieter Sues FLS Rainer R. Schoch 《Zoological Journal of the Linnean Society》2013,168(4):859-872
The holotype of cf. Halticosaurus orbitoangulatus Huene, 1932, comprises an incomplete and macerated but associated skull of an archosaurian reptile from the middle (second) Stubensandstein (middle Löwenstein Formation; Upper Triassic: Norian) of Baden‐Württemberg, Germany. It was originally interpreted as a theropod dinosaur but more recently it has been suggested that this taxon has crocodylomorph affinities. Detailed preparation of the holotype of cf. H. orbitoangulatus has revealed much new anatomical information and permitted reassessment of its affinities. The maxilla lacks both a distinct antorbital fossa and a medial bony lamina bordering the antorbital fenestra. The lateral surface of the dentary bears a pronounced horizontal ridge. The squamosal differs from that of basal crocodylomorphs in being L‐shaped rather than arcuate in dorsal view, lacking a dorsolateral overhang, and lacking an interlocking contact with the paroccipital process as, for example, in the basal crocodylomorph Saltoposuchus connectens from the same horizon and locality. Phylogenetic analysis placed cf. H. orbitoangulatus amongst loricatan pseudosuchians (but not amongst Crocodylomorpha) rather than amongst theropod dinosaurs. The holotype of cf. H. orbitoangulatus represents a previously unrecognized taxon of loricatan pseudosuchian, which is here named Apatosuchus orbitoangulatus and set apart from other known Norian‐age non‐crocodylomorph loricatans by its apparently much smaller size. © 2013 The Linnean Society of London 相似文献
39.
Chanjuan Guo Judy Simon Rainer Gasche Pascale Sarah Naumann Carolin Bimüller Rodica Pena Andrea Polle Ingrid Kögel-Knabner Bernd Zeller Heinz Rennenberg Michael Dannenmann 《Plant and Soil》2013,369(1-2):657-668
Aims
Our aims were to characterize the fate of leaf-litter-derived nitrogen in the plant-soil-microbe system of a temperate beech forest of Southern Germany and to identify its importance for N nutrition of beech seedlings.Methods
15N-labelled leaf litter was traced in situ into abiotic and biotic N pools in mineral soil as well as into beech seedlings and mycorrhizal root tips over three growing seasons.Results
There was a rapid transfer of 15N into the mineral soil already 21 days after tracer application with soil microbial biomass initially representing the dominant litter-N sink. However, 15N recovery in non-extractable soil N pools strongly increased over time and subsequently became the dominant 15N sink. Recovery in plant biomass accounted for only 0.025 % of 15N excess after 876 days. After three growing seasons, 15N excess recovery was characterized by the following sequence: non-extractable soil N?>>?extractable soil N including microbial biomass?>>?plant biomass?>?ectomycorrhizal root tips.Conclusions
After quick vertical dislocation and cycling through microbial N pools, there was a rapid stabilization of leaf-litter-derived N in non-extractable N pools of the mineral soil. Very low 15N recovery in beech seedlings suggests a high importance of other N sources such as root litter for N nutrition of beech understorey. 相似文献40.
Kishan?Kumar Chudasama Jonathon Winnay Stefan Johansson Tor Claudi Rainer K?nig Ingfrid Haldorsen Bente Johansson Ju?Rang Woo Dagfinn Aarskog J?rn?V. Sagen C.?Ronald Kahn Anders Molven P?l?Rasmus Nj?lstad 《American journal of human genetics》2013,93(1):150-157
The phosphatidylinositol 3 kinase (PI3K) pathway regulates fundamental cellular processes such as metabolism, proliferation, and survival. A central component in this pathway is the p85α regulatory subunit, encoded by PIK3R1. Using whole-exome sequencing, we identified a heterozygous PIK3R1 mutation (c.1945C>T [p.Arg649Trp]) in two unrelated families affected by partial lipodystrophy, low body mass index, short stature, progeroid face, and Rieger anomaly (SHORT syndrome). This mutation led to impaired interaction between p85α and IRS-1 and reduced AKT-mediated insulin signaling in fibroblasts from affected subjects and in reconstituted Pik3r1-knockout preadipocytes. Normal PI3K activity is critical for adipose differentiation and insulin signaling; the mutated PIK3R1 therefore provides a unique link among lipodystrophy, growth, and insulin signaling. 相似文献