A miniaturized assay to quantify effects of chemicals or physical stimuli upon locust activity

Solitary and gregarious locusts differ in many traits, such as body color, morphometrics and behavior. With respect to behavior, solitary animals shun each other, while gregarious animals seek each other＇s company, hence their crowding behavior. General activity, depending on the temperature, occurs throughout the day but is much lower in solitary locusts. Solitary locusts occasionally fly by night while gregarious locusts fly regularly during daytime （swarming）. In search of new assays to identify substances that control or modify aspects of （phase） behavior, we designed a simple activity assay, meant to complement existing behavioral measurement tools. The general activity is reflected in the number of wall hits, that is, the number of contacts between the locust and the vertical walls of a small arena. Using this single parameter we were able to quantify differences in total activity of both nymphs and adults of isolation-reared （solitary）, regrouped- and crowdreared （gregarious） locusts under different conditions. Furthermore, we demonstrate that there are inter- and intra-phase dependent differences in activities of 5th instar nymphs afar injections of the three different adipokinetic hormones.     

Development of nine polymorphic microsatellite loci in the spined loach, Cobitis taenia, and cross-species amplification in the related species C. elongatoides, C. taurica and C. tanaitica

Nine polymorphic microsatellite loci were developed for the spined loach, Cobitis taenia (Teleostei: Cobitidae). The loci were validated using 50 individuals from a population in Belgium. Moderate to high levels of polymorphism were detected (two to 11 alleles). In addition, most markers amplified successfully in three closely related taxa that are known to hybridize with C. taenia: C. elongatoides, C. taurica and C. tanaitica. Some of the loci are most likely diagnostic among species. These markers will be valuable for the study of the historical and contemporary interactions within C. taenia and the Cobitis species complex.     

WFS1在大鼠胰腺不同发育阶段的表达

目的:研究WFS1在胰腺发育不同阶段的表达和细胞定位.方法:运用Western Blot技术检测WFS1在大鼠胰腺发育不同阶段的蛋白表达水平;运用免疫荧光检测不同时期WFS1在胰腺的定位.结果:Western Blot结果显示WFSl的蛋白表达量胚胎后期高于新生期,成年期表达量上升;免疫荧光结果显示在不同发育时期WFS1与胰岛β细胞共表达.结论:WFS1在胚胎发育中后期的高表达可能与胰岛形成及功能完善有关,并且可能参与了胰岛重塑.     

Coupling of M3 Acetylcholine Receptor to Gq16 Activates a Natriuretic Peptide Receptor Guanylyl Cyclase

Muscarinic activation of tracheal smooth muscle (TSM) involves a M₃AChR/heterotrimeric-G protein/NPR-GC coupling mechanism. G protein activators Mastoparan (MAS) and Mastoparan-7 stimulated 4- and 10-fold the NPR-GC respectively, being insensitive to PTX and antibodies against Gα_i/o subfamily. Muscarinic and MAS stimulation of NPR-GC was blocked by antibodies against C-terminal of Gα_q16, whose expression was confirmed by RT-PCR. However, synthetic peptides from C-terminal of Gα_q15/16 stimulated the NPR-GC. Coupling of α_q16 to M₃AChR is supported by MAS decreased [³H]QNB binding, being abolished after M₃AChR-4-DAMP-alkylation. Anti-i₃M₃AChR antibodies blocked the muscarinic activation of NPR-GC, and synthetic peptide from i₃M₃AChR (M₃P) was more potent than MAS increasing GTPγ [³⁵S] and decreasing the [³H]QNB activities. Coupling between NPR-GC and Gα_q16 was evaluated by using trypsin-solubilized-fraction from TSM membranes, which displayed a MAS-sensitive-NPR-GC activity, being immunoprecipitated with anti-Gα_q16, also showing an immunoreactive heterotrimeric-G-β -subunit. These data support the existence of a novel transducing cascade, involving Gα_q16β γ coupling M₃AChR to NPR-GC.     

Bromeliads provide shelter against fire to mutualistic spiders in a fire‐prone landscape

1. A key challenge in the study of mutualistic interactions is understanding sources of variation that strengthen or weaken these interactions. In spider–plant mutualisms, spiders benefit plants by improving plant nutrition and protecting plants from herbivory. Although the benefits of plants to spider growth and survival are often claimed, they are rarely demonstrated. 2. In this study, empirical evidence is provided that bromeliads (Bromelia balansae, Bromeliaceae) are essential for the resilience of the mutualistic bromeliad‐living jumping spider populations (Psecas chapoda, Salticidae) after a fire event, sheltering spiders from the heat of the flames. 3. Spider populations were compared before and after a natural fire event and it was shown that spiders of different ages survived the fire. The survival of such individuals allowed the population of P. chapoda spiders to recover rapidly, returning to pre‐fire levels in 5 months. 4. Bromeliads reduced the susceptibility of P. chapoda spiders to burning, and this mutualistic relationship contributed to the resilience of the spider population after a fire event. It is suggested that frequent fires in fire‐prone landscapes may have strengthened this spider–plant relationship, contributing to the maintenance and evolution of this association.     

Simple scaling of photosynthesis from leaves to canopies without the errors of big-leaf models

In big-leaf models of canopy photosynthesis, the Rubisco activity per unit ground area is taken as the sum of activities per unit leaf area within the canopy, and electron transport capacity is similarly summed. Such models overestimate rates of photosynthesis and require empirical curvature factors in the response to irradiance. We show that, with any distribution of leaf nitrogen within the canopy (including optimal), the required curvature factors are not constant but vary with canopy leaf area index and leaf nitrogen content. We further show that the underlying reason is the difference between the time-averaged and instantaneous distributions of absorbed irradiance, caused by penetration of sunflecks and the range of leaf angles in canopies. These errors are avoided in models that treat the canopy in terms of a number of layers – the multi-layer models. We present an alternative to the multi-layer model: by separately integrating the sunlit and shaded leaf fractions of the canopy, a single layered sun/shade model is obtained, which is as accurate and simpler. The model is a scaled version of a leaf model as distinct from an integrative approach.     

Identification and Phylogenetic Relationships of Microsporidia by Riboprinting

ABSTRACT. The SSUrDNA and the ITS of different microsporidia from eight fishes, four insects and a shrimp were amplified and digested with restriction enzymes. The generated riboprints suggest a close evolutionary relationship between Glugea americanus and Spraguea lophii suggesting that Glugea americanus should be renamed Spraguea americanus and that the tissue infected and host origin should be considered of greater taxonomic importance for defining a genus than previously considered. Phylogenetic analysis of the riboprints demonstrates an unidentified microsporidium from a bumper fish ( Chloroscombrus chrysurus ) is related although not identical to Microgemma oviodea , a parasite from red band fish. We were also able to distinguish between Glugea anomala and Glugea atherinae and Glugea stephani but were not able to differenciate among the latter two. Insects isolates, Nosema costelytrae, N. bombycis, N. trichoplusiae, Nosema sp. and a shrimp isolate, Agmasoma penaei , are not related to the fish isolates.     

A specimen of Curculioninae (Curculionidae,Coleoptera) from the Lower Cretaceous,Araripe Basin,north‐eastern Brazil

Abstract: A specimen of Curculionidae (Curculioninae) is described as Arariperhinus monnei gen. et sp. nov. The specimen is preserved on a laminated limestone sample of the Crato Formation (Santana Group), Lower Cretaceous (Aptian–Albian), and was collected from a quarry near Nova Olinda, Chapada do Araripe, State of Ceará, Brazil. The genus is placed in the subfamily Curculioninae because of its strongly convex body and relatively slender rostrum, but mainly by its rounded eyes and lack of a prosternal sulcus and tibial spurs. The very prominent eyes in lateral view, a cylindrical rostrum and a straight posterior margin of ventrite II are strong indications that this fossil belongs to the tribe Anthonomini. However, the claws, which would resolve the exact placement of this fossil, are poorly preserved. Arariperhinus monnei gen. et sp. nov. is distinguishable by the combination of several characters and the first record of the family Curculionidae in the Santana Group; it is the oldest record of a member of the subfamily Curculioninae.