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Male aggression,limited female choice and the ontogeny of mating behaviour in the flesh fly Sarcophaga crassipalpis
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J. Dylan Shropshire Darrell Moore Edith Seier Karl H. Joplin 《Physiological Entomology》2015,40(4):325-335
Previous work has shown that male flesh flies (Sarcophaga crassipalpis Macquart) exhibit an ontogeny of behaviour from eclosion through sexual maturity that includes extensive changes in the expression of aggressive, non‐aggressive interactive and non‐interactive behaviours. To determine how the presence of a female flesh fly influences the manifestation of these behaviours, male flesh flies of different ages post‐eclosion are paired with same‐age females and their behaviours are monitored in a simple arena during a 50‐min observation period. All flies are socially isolated until pairing. Although the levels of expression of aggressive and non‐aggressive interactive behaviours are depressed relative to previous findings in male‐opponent pairs, the ontogeny of aggression still occurs as indicated by a significant increase, with age, in the agonistic behaviour ‘hold’. Similar to male‐opponent pairs and individual males, the performance by males of the non‐interactive behaviours ‘walking’ and ‘standing’ diminishes, whereas ‘upside‐down’ increases with age. By contrast, ‘grooming’ shows a significant age‐related decline. No courtship behaviours are observed in the males, although the aggressive behaviour ‘hold’ is a significant transition to mating. Females show no obvious courtship or rejection behaviours, although the significant increase in ‘upside‐down’ with age could possibly be a behavioural gateway to mating. The results of this study indicate that extensive age‐related changes encompassing the entire behavioural repertoire are intrinsic to male flesh flies and persist under a variety of different social contexts. 相似文献
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Samir Jabari Alexandre B. M. da Silveira Enio C. de Oliveira Karl Quint André Wirries Winfried Neuhuber Axel Brehmer 《Cell and tissue research》2014,358(1):75-83
Chagasic megacolon is accompanied by extensive myenteric and, simultaneously, moderate submucosal neuron loss. Here, we examined changes of the innervation pattern of the lamina propria (LP) and muscularis mucosae (MM). Two alternating sets of cryosections were taken from seven non-chagasic colonic and seven chagasic megacolonic specimens (the latter included both the dilated megacolonic and the non-dilated transitional oral and anal zones) and were immunohistochemically triple-stained for smooth-muscle actin (SMA), synaptophysin (SYN) and glial acid protein S100 and, alternatively, for SMA, vasoactive intestinal peptide (VIP) and somatostatin (SOM). Subsequent image analysis and statistical evaluation of nervous tissue profile areas revealed that, in LP, the most extreme differences (i.e. increase in thickness or decrease in nerve, glia and muscle tissue profile area, respectively) compared with control values occurred in the dilated megacolonic zone itself. In contrast, the most extreme differences in the MM were in the anal-to-megacolonic zone (except the profile area of muscle tissue, which was lowest in the megacolonic zone). This parallels our previous results in the external muscle coat. A partial and selective survival of VIP-immunoreactive in contrast to SOM-immunoreactive nerve fibres was observed in both mucosal layers investigated. Thus, VIPergic nerve elements might be crucial for the maintenance of the mucosal barrier. The differential changes of neural tissue parameters in LP and MM might reflect a multifactorial rather than a pure neurogenic development of megacolon in chronic Chagas’ disease. 相似文献
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This paper defines a collection of Drosophila deletion mutations (deficiencies) that can be systematically screened for embryonic phenotypes, orphan receptor ligands, and genes affecting protein localization. It reports the results of deficiency screens we have conducted that have revealed new axon guidance phenotypes in the central nervous system and neuromuscular system and permitted a quantitative assessment of the number of potential genes involved in regulating guidance of specific motor axon branches. Deficiency “kits” that cover the genome with a minimum number of lines have been established to facilitate gene mapping. These kits cannot be systematically analyzed for phenotypes, however, since embryos homozygous for many deficiencies in these kits fail to develop due to the loss of key gene products encoded within the deficiency. To create new kits that can be screened for phenotype, we have examined the development of the nervous system in embryos homozygous for more than 700 distinct deficiency mutations. A kit of ∼400 deficiency lines for which homozygotes have a recognizable nervous system and intact body walls encompasses >80% of the genome. Here we show examples of screens of this kit for orphan receptor ligands and neuronal antigen expression. It can also be used to find genes involved in expression, patterning, and subcellular localization of any protein that can be visualized by antibody staining. A subset kit of 233 deficiency lines, for which homozygotes develop relatively normally to late stage 16, covers ∼50% of the genome. We have screened it for axon guidance phenotypes, and we present examples of new phenotypes we have identified. The subset kit can be used to screen for phenotypes affecting all embryonic organs. In the future, these deficiency kits will allow Drosophila researchers to rapidly and efficiently execute genome-wide anatomical screens that require examination of individual embryos at high magnification. 相似文献
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Karl E. Anderson 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,543(3):313-327
Effects of a series of antihypertensive drugs on the activity of δ-aminolevulinate synthase and on the formation of porphyrins and cytochrome P-450 were examined in the 18-day-old chick embryo liver in ovo. Hydralazine, pargyline, phenoxybenzamine, clonidine, and spironolactone were found to induce δ-aminolevulinate synthase in this system. These drugs therfore have the potential to precipitate clinical expression in human hereditary hepatic porphyrias and should be avoided or used with caution in patients with these disorders. Differential effects of these and other drugs were observed in the avian liver, in that δ-aminolevulinate synthase was more commonly induced thatn were porphyrins and cytochrome -450; the synthase was usually highest 6–12 h after injection, whereas porphyrins and cytochrome P-450 were highest at 24 h. Furthermore marked porphyrin accumulation was not seen with many drugs that induce σ-aminolevulinate synthase and cytochrome P-450 but was more characteristic of compounds that reduced the metabolism of protoporphyrin to heme, such as 1,4-dihydro-3,5-dicarbethoxycollidne (DDC) and high dose of hydralazine. A sensitive and convenient method to test for capacity to induce heme biosynthesis was adapted for use in the chick embryo liver. This employed a relatively small “priming” dose (0.25 mg) of DDC given with a drug being tested and a fluorometric assay of porphyrins in a liver homogenate obtained at 24 h. This simple method should facilitate screening for those drugs which induce the synthesis of δ-aminolevulinate synthase and/or cytochrome P-450 and are potentially dangerous to patients with hereditary hepatic porphyria. 相似文献
17.
The filamentous green alga Klebsormidium flaccidum will produce zoospores when cultured on a diurnal regime of 8-hr light and 16-hr dark. Zoosporogenesis is inhibited by interruption of the dark period with light of sufficient intensity and duration. The relationship between intensity and maximum time of interruption before total inhibition of zoosporogenesis is nonlinear. 相似文献
18.
Axillary shoot producing cultures were obtained from microcuttings and shoot tips of Calluna vulgaris cv. H.E. Beale. For cultures derived from microcuttings the highest multiplication rate of 38 shoots (5 mm or longer) was obtained on a reduced salt medium with the addition of 0.5 mgl-1 2-isopentenyladenine (2iP) during an 8 week subculture. For shoot tip derived cultures 0.2 mgl-1 6-benzyladenine (BA) was the best cytokinin and led to a multiplication rate of 26 for a 6 week subculture. The addition of 1 g/l casein hydrolysate to a multiplication medium enhanced shoot proliferation in presence of 0.5 mgl-1 BA.Despite various auxin treatments shoots formed no roots in vitro but rooted readily if transferred to a peat substrate ex vitro. A high rooting percentage (80%) was also obtained with shoots taken from the end of a multiplication phase and rooted directly. An additional subculture on low auxin containing media before transfer to peat substrate is recommended because the shoot condition can be improved in this way. A high number of rooted plantlets was produced, so the methods described will allow mass propagation. 相似文献
19.
Summary In order to establish a transformation system for P. chrysogenum autonomously replicating vectors were constructed using mitochondrial DNA sequences from the fungus. A physical map of the mt DNA of a production strain was established using ten different restriction enzymes. Unexpectedly, the mt DNA of this strain proved to be significantly smaller than that of a second strain from a culture collection (27 kb versus 49 kb). Various fragments representing about 71% of the 27 kb mt DNA were cloned and, at first, preselected for replicating activity in an intermediate host (Saccharomyces cerevisiae). Two of these fragments also promoted autonomous replication in P. chrysogenum, which was confirmed by isolation of bulk DNA and transfer into E. coli. For selection of transformants in P. chrysogenum the prokaryotic kanamycin resistance gene was used which increased about twofold the resistance against G418.
Present address: Institut für Biotechnologie, Fachgebiet Mikrobiologie, Techn. Universität Berlin, Seestr. 13, D-1000 Berlin 65 相似文献
20.
Summary DNA from the kangaroo rat,Dipodomys ordii, contains a 3.3-kb, highly repeated sequence that is interspersed throughout the genome in small tandem clusters. One 3.3-kb unit has been cloned into pBR322 and the nucleotide sequence determined. The clone used was shown to be representative of the bulk of such sequences found in the genomic DNA. The sequence contains 10 homologous subunits each ca. 260 bp in length. Comparison of these to one another yielded a 258-bp consensus sequence containing a 35-bp terminal inverted repeat. Two unique stretches also occur. One of these contains a region that could serve as a promoter for RNA polymerase III; the other contains a sequence related to the ARS sequences of yeast. It is proposed that an ancestral sequence similar to the consensus sequence was amplified to 10 or more units, and that, subsequently, two other sequences were inserted. The properties of these insertions may have led to the dispersal of the sequence throughout the genome. 相似文献