摘要:

AbstractThe hemolymph of the adult femaleManduca sextawas fractionated by cascade‐mode multiaffinity chromatography (CASMAC) on a main‐line tandem column chain containing Zn2+‐TED, T‐gel, Ni2+‐DPA, and phenylsepharose and a side‐line column containing Zn2+‐DPA. The technique separated some of the previously described major hemolymph proteins, and yielded a number of fractions with simple composition. Some of these fractions contained only less abundant proteins ofManducahemolymph. Thus, it appears that CASMAC would be a very useful fractionation technique for purification and characterization of the minor proteins of insect hemolymph. © 1992 W

ISSN:0739-4462    

DOI:10.1002/arch.940200402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThe presence of allatostatins in the nerves of the antennal pulsatile organ muscle of the cockroachDiploptera punctatawas confirmed by immunocytochemistry, bioassay, and HPLC. Immunocytochemical reactivity with monoclonal antibody against allatostatin I showed strong allatostatin immunoreactivity in the antennal heart nerve which innervates this muscle with varicostities along the muscle fibers and in the insertion of the muscle on the pulsatile ampullae. Bioassay of Sep‐Pak purified muscle extract demonstrated inhibition of juvenile hormone synthesis by corpora allata in vitro. A dose‐response curve showed maximum inhibition of juvenile hormone synthesis was achieved with 10–20 pulsatile organ muscle eq/corpora allata, and 50% inhibition achieved with an estimated 2.6 pulsatile organ muscle eq. Two successive HPLC separations of the Sep‐Pak purified extract yielded bioactive fractions corresponding to the elution times of the five known allatostatins. © 1992 Wiley

ISSN:0739-4462    

DOI:10.1002/arch.940200403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractExperiments were conducted to determine whether the biogenic amines octopamine (OA) and 5‐hydroxytryptamine (5‐HT) exert modulatory effects on pheromone responsiveness and random locomotor activity in male gypsy moths. When injected into males, OA significantly enhanced sensitivity to pheromone, while 5‐HT enhanced general locomotor activity, results that were very similar to those previously shown for the cabbage looper. Maximal effect of the amines, however, was observed when injection occurred just prior to the onset of scotophase, rather than photophase, as we had originally hypothesized for this diurnally active insect. Male gypsy moths also displayed a prominent scotophase response, with sensitivity to pheromone greater in the scotphase compared with photophase, but with the level of random locomotor activity lower in scotophase than in photophase. The upwind flight behavior of males to a pheromone source in a wind tunnel, as well as the time spent at the source, were also significantly different in the two light regimes. Furthermore, when exposed to a 1 h scotophase (instead of the normal 8), or to continuous dark conditions, while males exhibited response to pheromone and locomotor activity during the same scotophase and photophase periods as observed in a 16:8 light : dark cycle, the levels of response, as well as qualitative aspects of the upwind flight behaviors in both periods were a function of the light intensity. Our combined results suggest that male gypsy moths display a bimodal rhythm of locomotor and pheromone response over the diel cycle, with light intensity and scotophase onset providing critical cues for the expression of behaviors, as well as the modulatory action of the amines. © 1992 Wiley‐L

ISSN:0739-4462    

DOI:10.1002/arch.940200404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractExperiments were conducted to determine the relationship between photoperiod cues and the modulatory action of octopamine (OA) on male sensitivity to sex pheromone in the cabbage looper moth. Results showed that levels of random locomotor activity and response to pheromone, as well as the effectiveness of OA in enhancing male sensitivity, were dependent on the light intensity during the scotophase period. The importance of scotophase onset was further demonstrated by the fact that a 1 h period of dark (instead of the normal 8) was sufficient to elicit male response to pheromone, and the modulatory action of the amine, several hours later in photophase conditions during the “expected” mid‐scotophase period when peak response normally occurs. Furthermore, expression of the response rhythms and the effect of octopamine were maximal when injection of the amine and scotophase onset occurred during a narrow temporal window around the expected time of scotophase onset. Delays or advances in scotophase onset or injection of octopamine resulted in decreased levels of behavior and loss of effectiveness of the amine. Studies involving a reversal in the photoperiod also support the idea that scotophase onset is a critical time in the regulation of the general locomotor and pheromone‐response rhythms exhibited by males. The combined results support a hypothesis that the modulatory action of octopamine is associated with physiological changes occurring at the onset of scotophase, and that the periodicity of this action is influenced by an endogenous oscillator. © 1992 Wiley

ISSN:0739-4462    

DOI:10.1002/arch.940200405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractThe lipophorin ofRhodnius prolixusmetabolically labelled with32P exclusively in the phospholipid moiety was purified on a potassium bromide gradient and treated with phospholipase A2in the presence of an excess of fatty acid‐free albumin. The treatment completely removed the phospholipids from the particles and generated [32P]‐lysophosphatidylcholine, [32P]‐lysophosphatidylethanoamine, and free fatty acids that remained bound to albumin. The phospholipid‐depleted lipophorin particles remained soluble, indicating that phospholipids are not essential in maintaining the stability of the particles in aqueous solution. Complete removal of phospholipids did not affect the association of apolipophorin III with lipophorin particles. Lipophorin density increased slightly from 1.120 to 1.134 g/ml after treatment. The phospholipid‐depleted particles aslo retained their ability to be recognized and loaded in vitro with phospholipids delivered by the fat body, thus supporting the concept of lipophorin's role as a reusable lipid shuttle for phospholipids. © 1992 Wiley

ISSN:0739-4462    

DOI:10.1002/arch.940200406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

摘要:

AbstractProteins present at high concentrations in hemolymph of the larval weevilDiaprepes abbreviatuswere previously shown to bind a synthetic coumarin, 7‐amino‐3‐phenyl coumarin (coumarin‐10). One of the two native proteins previously identified (protein I) is now shown to separate into two distinct bands (proteins la and lb) using native gradient pore‐limiting electrophoresis. The high concentration of proteins la, lb, and ll in larval hemolymph, their disppearance from hemolymph upon pupation, and an apparent hexameric structure shown by chemical crosslinking identify them as hexameric storage proteins (hexamerins). At least one chromatographic form of lb isolated by anion exchange HPLC is now shown to bind riboflavin (Rb). Binding was also demonstrated by quenching of Rb fluorescence by a partially isolated mixture of the storage proteins. Lipophorin did not quench Rb fluorescence. Rb was heat‐extracted from whole hemolymph and identified by its fluorescence spectra and by reverse phase HPLC with fluorescence detection. The two subunits shared by the three holoproteins have been isolated by sequential density gradient ultracentrifugation, gel permeation HPLC, and reverse phase HPLC. All three holoproteins shared the α subunit (M, 75,000), while the β subunit (M, 71,000) was lacking from one of the three. Repeated passage through an anion exchange column yielded two of the three proteins (lb and ll) in homogeneous form. Chemical crosslinking with dimethylsuberimidate indicated a hexameric structure for the holoproteins. All subunits and holoproteins stained as high mannose glycoproteins when probed with biotinylated concanavalin A on PVDF membranes. The α subunit was high in Met, His, and Thr, and the β subunit was high in Lys. Both were high in Pro and had approximately 16% Phe + Tyr. Sequences of the 20 N‐terminal amino acid residues of each subunit showed 45–60% homology between subunits. These coleopteran proteins also showed some sequential homology but no immunological cross‐reactivity with storage proteins from the lepidopteransGalleria mellonellaandHeliothis viresce

ISSN:0739-4462    

DOI:10.1002/arch.940200407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY

ISSN:0739-4462    

DOI:10.1002/arch.940200401

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1992

数据来源: WILEY