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1.
Gabrielle C. Winters Gianluca Polese Anna Di Cosmo Leonid L. Moroz 《Journal of morphology》2020,281(7):790-801
Neuropeptide Y (NPY) is an evolutionarily conserved neurosecretory molecule implicated in a diverse complement of functions across taxa and in regulating feeding behavior and reproductive maturation in Octopus. However, little is known about the precise molecular circuitry of NPY-mediated behaviors and physiological processes, which likely involve a complex interaction of multiple signal molecules in specific brain regions. Here, we examined the expression of NPY throughout the Octopus central nervous system. The sequence analysis of Octopus NPY precursor confirmed the presence of both, signal peptide and putative active peptides, which are highly conserved across bilaterians. In situ hybridization revealed distinct expression of NPY in specialized compartments, including potential “integration centers,” where visual, tactile, and other behavioral circuitries converge. These centers integrating separate circuits may maintain and modulate learning and memory or other behaviors not yet attributed to NPY-dependent modulation in Octopus. Extrasomatic localization of NPY mRNA in the neurites of specific neuron populations in the brain suggests a potential demand for immediate translation at synapses and a crucial temporal role for NPY in these cell populations. We also documented the presence of NPY mRNA in a small cell population in the olfactory lobe, which is a component of the Octopus feeding and reproductive control centers. However, the molecular mapping of NPY expression only partially overlapped with that produced by immunohistochemistry in previous studies. Our study provides a precise molecular map of NPY mRNA expression that can be used to design and test future hypotheses about molecular signaling in various Octopus behaviors. 相似文献
2.
In the albino mutant of an Okinawa strain of Locusta migratoria (L.) (Orthoptera: Acrididae), albinism is caused by the absence of the dark‐colour‐inducing neurohormone (DCIN), which is present in the corpora cardiaca (CC) of normally coloured phenotypes. This study tests whether the absence of DCIN is responsible for albinism in an albino mutant of another locust, Schistocerca gregaria (Forsk.) (Orthoptera: Acrididae). This seemed feasible because a single Mendelian unit controls albinism in both species. However, implantation of CC, or injection of an extract of CC, from albino donors of S. gregaria, induce dark coloration in crowded nymph recipients of the Okinawa albino mutant of L. migratoria, as effectively as do implanted CC, or injections of extract of CC, from normal phenotype donors of S. gregaria. Therefore, DCIN is present in the albino mutant of S. gregaria, and consequently, the albinism in this mutant is not caused by its absence. Implantation of CC, or injection of extracts of CC, from albino donors of S. gregaria to conspecific albino nymphs does not induce darkening. Only extremely high doses of synthetic DCIN injected into albino nymphs of S. gregaria are effective, inducing some darkening. The dose to induce such darkening in albino nymphs of S. gregaria is 50 nmol, ≈ 5 × 106 times higher than that (10 femtomol) needed to induce equivalent darkening in nymphs of the Okinawa albinos of L. migratoria. The results are discussed and some possible explanations of the observed effects outlined. 相似文献
3.
Tetiana Gren Bohdan Ostash Yaroslav Hrubskyy Stepan Tistechok Victor Fedorenko 《Folia microbiologica》2014,59(2):147-153
Bacteria-assisted bioremediation is widely recognized as a low-cost method to minimize the consequences of soil pollution with toxic metals originating from industrial sites. Strains used in bioremediation have to deal with high metal load via biosorption, reduction, bioprecipitation, metal sequestration, and/or chelation. Actinobacteria, and streptomycetes in particular, are considered a perspective group for bioremediation as natural soil inhabitants with extensive secondary metabolism. Nevertheless, there is no reference information on survival of the model streptomycetes in the presence of the most abundant metal pollutants. Also, there are no reports describing the selection approaches towards improvement of bioremediation properties. In this work, the resistance of Streptomyces coelicolor M145 and Streptomyces sioyaensis Lv81 to certain transition metals and their growth under different pH values are described for the first time. Spontaneous chromate-resistant S. sioyaensis Lv81-138 strain was selected in the course of this work. Strain Lv81-138 is the most efficient actinobacterial Cr(VI) reducer reported so far, capable of converting 12 mmol/L of Cr(VI) into Cr(III) in a medium supplemented with 50 mmol/L K2CrO4. 相似文献
4.
Leonid S Brown 《Photochemical & photobiological sciences》2004,3(6):555-565
In the last decade, several genome sequencing projects revealed the existence of previously unknown photoreceptors. Among those are eukaryotic rhodopsins of haloarchaeal type, mostly represented by fungal sequences. We have classified and analyzed seventy-seven of these fungal proteins, which show a high similarity of their putative transmembrane regions to those of bacteriorhodopsin. Those sequences can be divided into the two subgroups, fungal rhodopsins (RDs) and opsin-related proteins (ORPs), the latter lacking the lysine residue necessary for retinal binding. We have analyzed the conservation pattern of the residues known to have functional or structural importance in bacteriorhodopsin and discussed dramatic differences in the conservation between RDs and ORPs. We found many cases of multiple forms of RDs and/or ORPs and examined possible reasons for such multiplicity. For some species the reason may lie in functional photobiological diversification, while for the others it follows the pattern of evolutionary recent genome duplication and possible functional redundancy. 相似文献
5.
The cytogenetic and cytological effects induced in mouse cornea epithelium cells by 9 GeV protons and "standard" radiation have been studied. The RBE coefficients are different at different times of observation. ATP and AMP are shown to produce a protective effect on the frequency of formation of aberrant mitoses. DMF values for protons determined 24 and 72 h following irradiation are 1.8 +/- 0.2 and 1.7 +/- 0.2, respectively. 相似文献
6.
V A Fedorenko L I Starodubtseva S A Zavorotnaia N D Lomovskaia V N Danilenko 《Genetika》1989,25(4):626-634
Among mutants of Streptomyces coelicolor A3(2) studied which were sensitive to chloramphenicol (Cmls), strains sensitive to a number of antibiotics (ristomycin, tetracycline, polymyxin, lincomycin) amount of 46%. Antibiotic-sensitive mutants are capable to form different classes of resistant revertants with frequency varying from 10(-2) to 10(-6) in independent strains. Ristomycin-sensitive clones (Rims) have been found to occur with high frequency in Cmls strains and Cmlr revertants. Mutations mediating the Rims phenotype are mapped in a locus linked to the gene for resistance to chloramphenicol. The results obtained are discussed, in accordance with the notion about possible role of cml mutation in induction of secondary mutational changes in the genome of S. coelicolor A3(2). 相似文献
7.
Leonid A. Kulakov Vladimir N. Ksenzenko Vladimir V. Kochetkov Vladimir N. Mazepa Alexander M. Boronin 《Molecular & general genetics : MGG》1985,200(1):123-127
Summary The DNA homology and adsorption specificity of newly isolated virulent bacteriophages of P. aeruginosa have been studied. On the basis of this analysis all phages were divided into four groups: k, m, mnP78-like and mnF82-like bacteriophages. DNA's of k as well as m phages were shown to possess different restriction patterns although they have an extensive homology. Unlike other groups, k phages were characterized by the presence of T4 DNA ligase-repaired, single-chain breaks.Abbreviations kbp
kilobase pairs
- EM
electron microscopy 相似文献
8.
Abortive Infection of F-Plasmid-Containing Escherichia coli Cells by Bacterial Virus T7 Is Determined by the Right End of T7 Gene 1 总被引:1,自引:0,他引:1 下载免费PDF全文
Phage T7 infects male (F-plasmid-carrying) Escherichia coli cells abortively, whereas the closely related phage T3 grows normally. The inability or ability of phage to replicate in male host cells depends on whether the right end of gene 1 (coding for the phage-specific RNA polymerase) consists of T7 or T3 DNA base sequences. 相似文献
9.
10.
Gennadii. P. Astrakhantsev Natalia B. Yegoroval Vladimir V. Menshutkin Igor V. Pisulin Leonid A. Rukhovets 《Hydrobiologia》1996,322(1-3):153-157
The ecosystem response model described in this paper combines an ecosystem model and a three-dimensional circulation model of Lake Ladoga developed earlier by the authors. The ecosystem model describes the process of Lake Ladoga eutrophication, and its biological submodel describes changes in the phyto- and zooplankton. In the earlier model version, lake circulation was determined using a two-dimensional hydrodynamical model which was not completely adequate. The present model allows calculation of the distributions of phyto- and zooplankton and mineral phosphorus and nitrogen. One of its main advantages is that reliable computations of the ecosystem dynamics over an extended period of time are possible. The response of the ecosystem to different levels of phosphorus pollution loading and to weather conditions is studied. 相似文献