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PubMed1993

Molecules and cognition: the latterday lessons of levels, language, and lac. Evolutionary overview of brain structure and function in some vertebrates and invertebrates.

The characteristics of the nervous systems of a number of organisms in different phyla are examined at the recombinant DNA, protein, neuroanatomic, neurophysiological, and cognitive levels. Among the invertebrates, special attention is paid to the advantages as well as the shortcomings of the fly Drosophila melanogaster, the worm Caenorhabditis elegans, the honey bee Apis mellifera, the sea hare Aplysia californica, the octopus Octopus vulgaris, and the squid Loligo pealei. Among vertebrates, the focus is on Homo sapiens, the mouse Mus musculus, the rat Rattus norvegicus, the cat Felis catus, the macaque monkey Macaca fascicularis, the barn owl Tyto alba, and the zebrafish Brachydanio rerio. Vertebrate nervous systems have also been compared in fossil vs. extant organisms. I conclude that complex nervous systems arose in the Early Cambrian via a big bang that was underpinned by a modular method of construction involving massive pleiotropy of gene circuits. This rapidity of construction had enormous implications for the degrees of freedom that were subsequently available to evolving nervous systems. I also conclude that at the level of neuronal populations and interactions of neuropiles there is no model system between phyla except at the basic macromolecular level. Further, I argue that to achieve a significant understanding of the functions of extant nervous systems we need to concentrate on fewer organisms in greater depth and manipulate genomes via transgenic technologies to understand the behavioral outputs that are possible from an organism. Finally, I analyze the concepts of "perceptual categorization" and "information processing" and the difficulties involved in the extrapolation of computer analogies to sophisticated nervous systems.

Animals↗
PubMed2002

The effects of phytochemical pesticides on the growth of cultured invertebrate and vertebrate cells.

A range of cultured cells of invertebrate and vertebrate origin was grown in the presence of a number of phytochemical pesticides to test the effect of the latter on cell proliferation. The main observation was that azadirachtin was a potent inhibitor of insect cell replication, with an EC50 of 1.5 x 10(10) M against Spodoptera cells and of 6.3 x 10(9) M against Aedes albopictus cells, whilst affecting mammalian cells only at high concentrations (> 10(-4) M). As expected, the other phytochemical pesticides, except for rotenone, had little effect on the growth of the cultured cells. Rotenone was highly effective in inhibiting the growth of insect cells (EC50:10(-8) M) but slightly less toxic towards mammalian cells (EC50:2 x 10(-7) M). Neem terpenoids other than azadirachtin and those very similar in structure significantly inhibited growth of the cell cultures, but to a lesser degree. The major neem seed terpenoids, nimbin and salannin, for example, inhibited insect cell growth by 23% and 15%, respectively.

Animals↗
PubMed2004

Aquatic toxicity of four alkylphenols (3-tert-butylphenol, 2-isopropylphenol, 3-isopropylphenol, and 4-isopropylphenol) and their binary mixtures to microbes, invertebrates, and fish.

The acute and chronic toxicity of four simple alkylphenols with butyl and propyl substitutions was evaluated with aquatic microbes, invertebrates, and fish. These alkylphenols-3-tert-butylphenol, 2-isopropylphenol, 3-isopropylphenol, and 4-isopropylphenol-have been detected in various environmental media, but their impact on aquatic fauna has seldom been evaluated. Relative susceptibility to each phenolic varied by test species. The marine bacterium Vibrio fischeri was the most susceptible to the alkylphenols, up to 3 orders of magnitude more sensitive than species of higher trophic levels. For 4-isopropylphenol, the 5-min Microtox EC(50) value was 0.01 mg/L, whereas the EC(50) for Ceriodaphnia after a 48-h exposure was 10.1 mg/L. Notable differences in sensitivity to the alkylphenols was also observed with the Microtox assay: 4-isopropylphenol was > 200 times more toxic to V. fischeri than was 2-isopropylphenol (EC(50) = 2.72 mg/L). For V. fischeri, the mixture toxicity of the alkylphenols was additive in nature and was predicted by a concentration addition model. The energy of the lowest unoccupied molecular orbital (ELUMO) explained the observed toxicity of the individual alkylphenols to V. fischeri (r(2) = 0.92, p < 0.05). These results suggest that the mode of action of polar narcotic alkylphenols to V. fischeri is different than that of other test organisms, possibly because of the differences in the cell structure of the prokaryotic V. fischeri.

Animals↗
PubMed1995

Invertebrate and vertebrate immune cells express pro-opiomelanocortin (POMC) mRNA.

We show here that hemocytes and leukocytes with phagocytic activity from both invertebrates (Planorbarius corneus, Viviparus ater) and vertebrates (Carassius auratus, Rana esculenta) express pro-opiomelanocortin (POMC) mRNA, as assessed by in situ hybridization with a digoxigenin-labeled human DNA probe. These data are in accord with previous observations from our laboratories on the presence in these cells of POMC-derived peptides and strongly suggest that these molecules--highly conserved throughout evolution--play an important role in cell locomotion and phagocytosis. POMC mRNA was also detected in lymphocytes of R. esculenta, but not of C. auratus, suggesting that from anuran amphibians onwards lymphocytes also express this gene. This phenomenon could be related to the appearance of more than one immunoglobulin isotype in anurans.

Animals↗
PubMed1995

Influence of 3,4-dichloroaniline (3,4-DCA) on benthic invertebrates in indoor experimental streams.

The influence of 3,4-dichloroaniline (3,4-DCA) on benthic invertebrates has been examined. Acute toxicity tests were carried out with the following species: Pristina longiseta, Aelosoma variegatum (Oligochaeta), Hydrozetes lacustris (Acarina), Planorbarius corneus, and Gyraulus albus (Planorbidae). LC50 values (96 hr) were obtained for Pri. longiseta (2.5 mg/liter) and for Hy. lacustris (4.7 mg/liter). For all other species ranges of toxicity (maximal concentration with 0% dead to minimum concentration with 100% dead) were determined. These ranges were 0.8-20 mg/liter 3,4-DCA for Pri. longiseta, 1.6-20 mg/liter, 3,4-DCA for Hy. lacustris, 10-20 mg/liter 3,4-DCA for G. albus, 50-100 mg/liter 3,4-DCA for Pl. corneus, and 10 mg/liter 3,4-DCA (maximal concentration with 0% dead; minimum concentration with 100% dead was not determined) for Ae. variegatum. In two experimental streams, the recolonization of benthic organisms into defined sample areas was studied. Therefore, a phase without chemical treatment was compared with a following exposure phase. Test concentrations were 0.2 and 1.4 mg/liter 3,4-DCA (nominal concentrations). Significant effects were the complete extinction of Pri. longiseta in 0.2 mg/liter 3,4-DCA within the first 3 weeks of exposure, as well as the reduction of immigrating individuals of another species of Pristina in both test concentrations, and of Hy. lacustris and Stentor sp. in 1.4 mg/liter 3,4-DCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Aniline Compounds↗
PubMed1999

Invertebrate tissue inhibitor of metalloproteinase: structure and nested gene organization within the synapsin locus is conserved from Drosophila to human.

Vertebrate tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix metalloproteinases and are thus involved in a wide variety of developmental and physiological processes. By identifying cDNAs of a transcript detected within an intron of the Drosophila synapsin gene we have cloned the Drosophila TIMP gene (Timp), which represents the first invertebrate member of the TIMP gene family. Sequence analysis revealed an open reading frame of 210 amino acids with 35% identity to human TIMPs and a conserved exon-intron structure. Analysis of sequence data from the Sanger Centre demonstrated that the human TIMP3 gene is encoded within intron V of the human synapsin-III gene, indicating that the nested organization of TIMP and synapsin genes may be a general feature conserved in evolution. We therefore speculate that the human TIMP4 gene will be located in intron V of the human synapsin-II gene on chromosome 3p25, and we present preliminary evidence that a human synapsin-IV gene is located near the TIMP2 gene on chromosome 17q23-q25.

Amino Acid Sequence↗
PubMed2002

Intraguild predation, invertebrate predators, and trophic cascades in lake food webs.

The top-down and bottom-up properties of model food webs that include intraguild predation and self-limiting factors such as cannibalism are investigated. Intraguild predation can dampen or even reverse the top-down effects predicted by food chain theory. The degree of self-limitation among the intraguild prey is a key factor in determining the direction and strength of the top-down response. Intraguild predation and self-limiting factors can also substantially alter the bottom-up effects of enrichment. These results can help explain the disparate results of trophic cascade experiments in lakes, where cascades are usually seen when large Daphnia are the primary herbivores, but not when smaller-bodied herbivores are dominant. Top-down manipulations should cascade at least modestly to phytoplankton in those lakes whose food web can be reasonably approximated by a chain (typically, those where Daphnia is the dominant herbivore), as predicted by food chain theory. On the other hand, smaller-bodied zooplankton are often preyed upon heavily by invertebrate predators as well as by planktivorous fish, thereby introducing elements of intraguild predation into these food webs. In this case, conventional food chain theory is likely to give incorrect predictions. Very large cascade effects may be due primarily to regime shifts between intraguild predation-dominated food webs and those that more resemble food chains, rather than due to the simple food chain cascade usually considered.

Animals↗
PubMed1995

A phylogenetic analysis of vertebrate and invertebrate Notch-related genes.

Members of the Notch gene family are thought to mediate inductive cell-cell interactions during development of a wide variety of vertebrates and invertebrates. These genes encoded transmembrane proteins that appear to act as receptors and contain three repeated sequence motifs. Two of these motifs (an epidermal growth factor-like sequence and a cdc10/SWI6/ankyrin sequence) have been found in a large number of unrelated proteins, while the third motif (a lin-12/Notch/glp-1 sequence) is unique to proteins of the Notch family. We present a phylogenetic analysis of 17 Notch-related genes from eight species that has implications as to the origins and relative functions of these genes in different species. Several independent gene duplications have occurred and at least one such duplication in the vertebrate lineage preceded the avian/mammalian divergence. Significantly, the overall organization of individual members of each internally repeated motif appears to have been conserved among species, suggesting that each repeat plays a unique role in protein function. Yet, where sequence divergence does occur among genes in vertebrate, dipteran, and nematode lineages, it may signify functional differences for specific regions in Notch-related proteins.

Animals↗
PubMed2000

Why and how marine-invertebrate larvae metamorphose so fast.

It is argued that larviparous development has evolved at least eight times among extant animals. A 'need for speed hypothesis' is proposed to explain profound convergence on a pattern of small larvae and rapid metamorphosis across six marine invertebrate clades. Shared selection pressures include limits to larval size, the plankton-to-benthos transition, extreme hazards on the benthos, and the profound helplessness of metamorphosing animals. The adaptive mechanisms include: (1) development of juvenile structures in larvae before they are metamorphically competent; (2) external cues trigger metamorphosis; and (3) rapid cell-to-cell conductance of the metamorphic signal to bring about rapid loss of larval structures and release of juvenile structures. Both pattern and mechanisms contrast in every regard with those of the other two major larviparous clades, Insecta and Amphibia.

Adaptation, Physiological↗
PubMed1987

Quantification and characterization of metallothioneins in tissues of lower vertebrates and invertebrates.

Metallothionein (MT) and the related metal-binding proteins in tissues of lower vertebrates and invertebrates were isolated by gel filtration chromatography (conventional liquid and high performance liquid chromatography). The metal-binding proteins including MT were detected by determining the metals bound to the proteins by atomic absorption spectrophotometry. This analytical procedure was recommendable as the first step to characterize unknown metal-binding proteins in diverse living bodies. As MT in the lower vertebrates, avian (Japanese quail), reptilian (tortoise), amphibian (8 species of frogs and 2 species of tailed amphibians) and fish MTs were isolated and characterized. The number of isoMTs was different among animals belonging not only to different classes but also to different species in the same family. One of the isoMTs in the avian, reptilian and amphibian MTs was shown to contain one histidinyl residue. Cadmium(Cd)-binding proteins were induced in three species of insect (Insecta, Arthropoda) larvae (midge, fleshfly and silkworm) by loading of Cd. Distribution of Cd in insect tissues was different among the three species though the alimentary canal was commonly the most important tissue for the storage of Cd in all species. Further, Cd in the soluble fractions was bound to inducible proteins of different molecular sizes in the three species. Cd-binding protein was also detected in the waterflea (Crustacea, Arthropoda) after loading of Cd. Cd-binding proteins induced in the earthworm (Oligochaeta, Annelida) by loading of Cd were a mixture of proteins with three different molecular sizes. One of the Cd-binding proteins with an apparent molecular size of 7,000 was shown to have characteristics of MT.

Amphibians↗
PubMed2006

Trisoxazole macrolides from Hexabranchus nudibranchs and other marine invertebrates.

Trisoxazole macrolides are cytotoxic and antifungal metabolites initially isolated from the egg-ribbons of the Hexabranchus nudibranch and later found in other marine invertebrates. They possess a characteristic macrolide portion, in which three contiguous oxazole units are integrated, and a side-chain with an N-methyl-vinylformamide terminus. The planar structures of the first members of this group, ulapualides and kabiramide C, were determined by interpretation of spectral data in conjunction with chemical degradation. Following these studies, the structures of approximately 35 congeners have been reported, including mycalolides from a marine sponge Mycale sp. The absolute stereochemistry of mycalolides was determined by chemical methods. Trisoxazole macrolides depolymerize F-actin and form a 1:1 complex with G-actin, thereby exhibiting potent toxicity toward eukaryotic cells. X-ray crystallography established the mode of binding of some of the members to G-actin and their absolute stereochemistry.

Actins↗
PubMed2004

Functional convergence of invertebrate and vertebrate cytokine-like molecules based on a similar lectin-like activity.

It is generally accepted that the action of cytokines results from their binding to specific receptors. However, many cytokines possess lectin-like activity that may be essential for the expression of their full biological activities. This review focuses on the physiological relevance of the lectin-like activity of cytokines during the innate immune response in mammals, using TNF as an illustrative example. Moreover, we will show that TNF displays functional analogies with a defense molecule from the earthworm Eisenia foetida termed CCF. These analogies are not reflected by primary sequence homology between CCF and TNF but are particularly based on a similar lectin-like activity/domain. Hence, from a phylogenetic point of view, the lectin-like activity/domain of CCF and TNF may represent an essential recognition mechanism that has been functionally conserved during the innate immune response of invertebrates and vertebrates as a result of convergent evolution.

Animals↗
PubMed1977

Evidence for new catecholamines or related amino acids in some invertebrate sensory neurons.

In certain sensory neurons of many different invertebrate species, including the sea anemones. Metridium senile and Tealia felina and the crustacean Artemia salina, fluorophores are formed during the course of the fluorescent histochemical technique of Falck-Hillarp. The presumed catecholamine nature of the neuronal fluorogenic compound was investigated by microspectrofluorometry, and the spectral characteristics of the fluorescence in the taxonomically different species was found to be very similar (excitation maximum at 375 nm with a smaller peak or shoulder at 330 nm and sometimes a shoulder in the spectrum at 410 nm; emission maximum at 475 nm). The emission maximum coincides with that of the catecholamines and DOPA (475 nm). The excitation maximum (375 nm) directly after formaldehyde treatment, however- differs from that of the catecholamines and DOPA (410 nm), but is similar to the excitation maximum displayed by these catechol derivatives at acid pH. The spectral characteristics of the fluorophore in the sensory cells might therefore theoretically be explained by an acid pH in the cells. This means improbable, however, and it is suggested that the phenomenon is due to the presence of unknown catechol derivatives. Analyses of the pH-dependent spectral changes indicate that the presumed catechol derivative in Tealia felina is beta-hydroxylated, whereas that in Artemia salina is not.

Amino Acids↗
PubMed1992

In vitro screening of crude extracts and pure metabolites obtained from marine invertebrates for the treatment of breast cancer.

A total of 15 samples (crude extracts and pure secondary metabolites) obtained from marine invertebrates collected from the offshore waters of British Columbia, Papua New Guinea, and Sri Lanka have previously been shown to exert cytotoxic activity in the in vitro L1210 leukemic bioassay. We screened these metabolites for in vitro cytotoxic activity against the drug-sensitive breast-tumor cell lines MCF-7, T-47D, ZR-75-1, and MDA-MB-231; the multidrug-resistant and P-glycoprotein (Pgp)-positive breast-tumor cell lines MCF-7 Adr and MDA-A1r; and normal and malignant human breast epithelial cells (HBEC) in primary culture. Eight samples exhibited significant [drug concentration resulting in a 50% decrease in cell growth as compared with controls (ED50), less than 25 micrograms/ml] dose-dependent cytotoxicity against the drug-sensitive cell lines; the ED50 values were as low as 0.004 micrograms/ml. Five of the eight samples exhibited significant cytotoxicity against the multidrug-resistant cell lines; the ED50 values were as low as 0.0006 micrograms/ml. Incubation of MCF-7 Adr cells with varying concentrations of compounds in the presence of Adriamycin demonstrated that none of the compounds tested interfered with Pgp function. Results obtained using HBEC in primary culture showed a wide range of chemosensitivities for a given drug against tissue taken from different patients, demonstrating the uniqueness of the response of different individuals to chemotherapy.

Animals↗
PubMedDate not supplied

Short-term experimental acidification of a Welsh stream: toxicity of different forms of aluminium at low pH to fish and invertebrates.

A 24-hr dosing experiment was carried out in a soft-water stream in upland Wales during which four separate zones were created by the simultaneous addition of sulphuric acid, aluminium sulphate, and citric acid. An upstream control zone (A), an acid zone pH 4.9 (B), an aluminium and acid (total filterable aluminium 0.27 mg/L, pH 4.9) zone (C) and a downstream zone (D) of aluminium complexed with citrate at low pH (total filterable aluminium 0.23 mg/L, pH 4.9). Test species exposed in all zones were the invertebrates Gammarus pulex (L.), Baetis rhodani (Pict.), Ephemerella ignita (Poda) and the fish Salmo salar L., Salmo trutta L. and Cottus gobio L. Response criteria measured were mortality, feeding, effects of pretreatment, brief-exposure, and the ability of animals to recover. Minimal effects were observed in the control and acid zones whilst large mortalities and reduced feeding were recorded in the acid and aluminium zone. These effects were significantly reduced in the acid, aluminium and citrate zone due to complexation of aluminium with citrate.

Aluminum↗
PubMed1990

Invertebrate neuropeptides resembling vasotocin and some analogues: synthesis and pharmacological properties.

The solid phase synthesis of three invertebrate vasopressin-oxytocin homologs: AVP-like factor, F1(1), ([Leu2, Thr4] AVT)2 isolated from subesophageal and thoracic ganglia of Locusta migratoria3, Arg-conopressin-S4. ([Ile2, Arg4] AVT), Lys-conopressin-G4 ([Phe2, Arg4] LVT), both isolated from the venom of fish-hunting marine snails of the genus Conus and six of their analogues is reported. These analogues are: [Arg4] AVT, [Ile2] AVT, [Leu2] AVT, [Phe2, Arg4] AVT, [Arg4] LVT and [Ile2, Arg4] LVT. All peptides were tested for antidiuretic and vasopressor activities.

Animals↗
PubMed1990

Hemolysins: pore-forming proteins in invertebrates.

Invertebrates possess lytic molecules which lyse vertebrate erythrocytes. In all the species studied so far, hemolytic activity depends on proteins which possess a wide range of reactivity. It is generally calcium-dependent and heat-labile, although calcium-independent and heat-stable hemolysins have also been detected. The molecules interact with sugars or lipids which could represent the membrane receptors by which circular lesions on target membranes are produced. On the basis of some analogies with vertebrate lytic molecules it is conceivable that the hemolysins evolved from a common ancestral gene which also led to vertebrate pore-forming proteins.

Animals↗