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PubMed1997

Intracellular injections of a soluble sperm factor trigger calcium oscillations and meiotic maturation in unfertilized oocytes of a marine worm.

How sperm trigger activating calcium transients in eggs remains a central, unresolved question in fertilization biology. To determine if a soluble sperm factor can generate a fertilization-like calcium response in the absence of sperm-egg binding, aqueous extracts of sperm from the nemertean worm Cerebratulus lacteus were mixed with Ca2+-sensitive fluorescent dyes and injected into unfertilized, metaphase-I-arrested oocytes. Based on confocal imaging analyses, unfertilized oocytes that had been injected with sperm extract routinely produced oscillating Ca2+ waves and resumed meiotic maturation in a manner that closely resembled normal fertilization. Calcium oscillations and maturation were typically lacking in control oocytes that had been (i) injected with buffer alone or with buffer containing added calcium, (ii) given external treatments of the sperm factor, or (iii) injected with extracts made from cells other than sperm. Boiling or protease treatment essentially abolished the potency of the sperm extract, and nonboiled extracts retained full activity in >10-kDa fractions, but not in <10-kDa fractions. Collectively, such findings suggest that the sperm of C. lacteus possess a soluble protein that can bypass oolemmal surface receptors to act within the ooplasm as a trigger of repetitive Ca2+ waves and meiotic maturation. Results obtained in this study are discussed with respect to the minimum amount of extract needed for egg activation and whether the oscillogenic substance is sufficiently concentrated in a single sperm to play a biological role during fertilization.

Animals↗
PubMed1997

MAP and cdc2 kinase activities at germinal vesicle breakdown in Chaetopterus.

In frog oocytes, activation of mitogen-activated protein kinase (MAPK, ERK) leads to activation of cdc2 and germinal vesicle breakdown (GVBD). By contrast, in starfish, MAPK is activated after GVBD. Here we have examined the relative involvements of MAPK and cdc2 in GVBD of Chaetopterus oocytes. MAPK was rapidly tyrosine-phosphorylated and activated (within 1-2 min) in response to exposure of the oocytes either to natural seawater (the normal trigger of GVBD in this organism) or to the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA), which can also elicit GVBD. This response preceded the tyrosine dephosphorylation and activation of cdc2 by several minutes. MAPK phosphorylation and activation were transient, lasting only until GVBD occurred and the spindle migrated to the cortex. The enzyme was not phosphorylated again as a result of egg activation. These results are consistent with the hypothesis that the activation of MAPK has a role in GVBD. However, PD 98059, a potent and selective inhibitor of MEK, the protein kinase that phosphorylates and activates MAPK, blocked the phosphorylation of MAPK but did not block GVBD, the dephosphorylation and activation of cdc2, or spindle formation and migration. Oocytes that underwent GVBD in PD 98059 could be fertilized and cleaved normally. Ionophore A23187, although it caused germinal vesicles to disappear and caused transient phosphorylation of MAPK, did not cause dephosphorylation of cdc2, and therefore this disappearance is artifactual. These results suggest that MAPK activation is neither obligatory nor sufficient for either GVBD or meiotic metaphase arrest in Chaetopterus and that activation of MAPK and cdc2 occur on independent, parallel pathways.

Animals↗
PubMed2000

Expression patterns of anterior Hox genes in the polychaete Chaetopterus: correlation with morphological boundaries.

Expression patterns for five Hox genes were examined by whole-mount in situ hybridization in larvae of Chaetopterus, a polychaete annelid with a tagmatized axial body plan. Phylogenetic analysis demonstrates that these genes are orthologs of the Drosophila genes labial, proboscipedia, zen, Deformed, and Sex combs reduced and are termed CH-Hox1, CH-Hox2, CH-Hox3, CH-Hox4, and CH-Hox5, respectively. Expression studies reveal a biphasic expression pattern. In early larval stages, well before any indications of segmental organization exist, a novel pattern of expression in bilateral posterior proliferating cell populations, corresponding to the teloblasts, was detected for each of the genes, with CH-Hox1 and CH-Hox2 expressed before the remaining three. In middle larval stages, all five genes are expressed in bilateral strips along the ventral midline, corresponding with the developing ventral nerve cord. In addition, CH-Hox1 and CH-Hox2 show strong expression at the foregut-midgut boundary. By late larval stages the expression is generally confined to the ventral CNS and ectoderm of the anterior parapodia. Anterior boundaries of expression are "colinear," at later larval stages, with CH-Hox2 expressed most rostrally, in the first segment, and anterior expression boundaries for CH-Hox1, CH-Hox3, CH-Hox4, and CH-Hox5 in segments 2, 3, 4, and 5, respectively. Like vertebrates and spiders, but unlike insects, CH-Hox3 participates in this colinear axial expression pattern. CH-Hox1 and CH-Hox2 have distinct posterior boundaries of expression in the ninth segment, which corresponds to a major morphological boundary, and may reflect a reorganization of Hox gene regulation related to the evolutionary reorganization of the Chaetopterus body plan.

Amino Acid Sequence↗
PubMed2002

Toxicity of 4-nonylphenol to Tubifex tubifex and Chironomus riparius in 28-day whole-sediment tests.

Concern has been growing recently over the toxicity and the mimicking properties of 4-nonylphenol (4NP), the most persistent breakdown product of the nonionic surfactant nonylphenol ethoxylates, broadly used in industrial cleaning processes. Twenty-eight-day tests were performed to evaluate the toxicity and the effects on reproduction of 4NP spiked sediment to the benthic invertebrates Tubifex tubifex and Chironomus riparius. 4NP was directly added to the wet sediment, avoiding any solvent. The EC50 value for the emergence of chironomids was 380 microg 4NP g(-1) dry weight (dw); the EC50 values for the deposition of cocoons and the development of young worms were very similar (428 and 420 microg g(-1) dw, respectively). Regarding NP estrogenic activity and its effects on reproduction and development, no significant differences were noted in the sex ratio of the emerged chironomids when exposed to 4NP compared to the controls, but the emerged chironomids did not lay eggs at concentrations higher than the EC10 (250 microg 4NP g(-1) dw). Furthermore, at concentration of 610 microg 4NP g(-1) dw an interference in the development of the gonads of adult worms was observed, but it was impossible to determine whether this effect was due to 4NP toxicity or to its hormone mimicking properties.

Age Factors↗
PubMed2001

Chemical defense in the egg masses of benthic invertebrates: an assessment of antibacterial activity in 39 mollusks and 4 polychaetes.

Many marine invertebrates deposit benthic egg masses that are potentially vulnerable to microbial infection. To help counter this threat these species may have evolved some form of chemical protection for their encapsulated embryos. In this study the egg masses from 7 marine mollusks were tested for antibacterial activity against 4 marine pathogens: Enterococcus sericolicida, Vibrio anguillarum, Vibrio alginolyticus, and Vibrio harveyi. Extracts from all of these egg masses were found to inhibit the growth of at least 1 marine bacterium at concentrations that approximate the natural concentration of extract in the egg masses. The egg masses of 39 mollusks and 4 polychaetes were then tested for antibacterial activity against 3 human pathogenic bacteria; Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Activity was detected in the egg masses from 34 species, including 2 polychaetes and mollusks from two classes and 18 families. Antibacterial activity in molluskan egg masses was found to extend across the marine, estuarine, freshwater, and terrestrial environments. Both gelatinous egg masses and tough egg capsules were found to inhibit microbial growth, suggesting that physical protection alone may not be sufficient to protect the eggs. Antimicrobial activity was observed in the fresh egg masses but not in the well-developed egg masses of a subset of species. The results of this study indicate that a wide range of invertebrates use chemical defense to protect their early stage embryos against bacterial infection.

Animals↗
PubMed1994

Evolution of phosphagen kinase. Primary structure of glycocyamine kinase and arginine kinase from invertebrates.

Of the six phosphagen kinases found in animals, the primary structure is known only for creatine kinase. Here we report three cDNA-derived or chemically determined amino acid sequences of two kinds of phosphagen kinases: a glycocyamine kinase from the polychaete Neanthes diversicolor (Annelida) and arginine kinase from the abalone Nordotis madaka (Mollusca) and the shrimp Penaeus japonicus (Arthropoda). Like vertebrate creatine kinases are monomers. These enzymes consist of 350 to 390 amino acid residues, and have a calculated molecular mass of 39,900 to 44,500 Da. Neanthes glycocyamine kinase shows 50 to 58% sequence similarity with vertebrate and invertebrate creatine kinases, having the greatest similarity (57 to 58%) with vertebrate mitochondrial creatine kinase isoform. It shows lower, but significant similarity (37 to 39%) with invertebrate arginine kinases. The sequence similarity between Nordotis and Penaeus arginine kinases is 51%. A phylogenetic tree constructed from 14 amino acid sequences of phosphagen kinases showed that they can be separated into three major clusters corresponding to creatine kinase, glycocyamine kinase and arginine kinase. The cluster of glycocyamine kinase is apparently closer to that of creatine kinase than arginine kinase. The cluster of creatine kinase is composed of several subclusters, each corresponding to three vertebrate isoforms and the invertebrate enzyme.

Amino Acid Sequence↗
PubMed1994

Glycera dibranchiata hemoglobin. X-ray structure of carbonmonoxide hemoglobin at 1.5 A resolution.

The structure of carbonmonoxide Glycera hemoglobin has been determined to 1.5 A resolution by X-ray diffraction. The model, including ordered solvent, has been refined by the method of restrained least-squares to an R-value of 0.146. The positions of 1104 protein atoms and the oxygens of 155 water molecules have been determined with an estimated r.m.s. error of 0.10 to 0.13 A. The r.m.s. errors in protein geometry are 0.027 A for bond distances, 0.038 A for angle distances and 0.012 A for deviations of planar groups from their least-squares planes. The iron lies exactly in the plane of the heme nitrogens and the heme is very slightly domed toward the proximal side. The carbon-oxygen bond in the carbon monoxide ligand is bent 7.9 degrees away from the normal to the plane of the heme nitrogens. The ligand is in close contact with, and slightly removed from the heme normal by distal residues Leu 58(E7) and Val62(E11). Comparison of the CO structure with the 1.5 A deoxy structure shows that the majority of the rather small structural changes occurring upon ligation are mediated by movement of the heme due to shortening of the five iron to nitrogen bonds. There is very little empty space inside the molecule, and no direct channel from the solvent into the heme pocket; however, rotation of the side-chain of the distal leucine residue Leu 58(E6) could provide a ligand pathway.

Animals↗
PubMed1996

Three-dimensional reconstruction of the chlorocruorin of the polychaete annelid Eudistylia vancouverii.

The chlorocruorin of the polychaete Eudistylia vancouverii observed in the electron microscope in vitreous ice, was subjected to a three-dimensional (3D) reconstruction by the random conical tilt series method. The 3D volume with a resolution of 35 A reconstructed from 1062 images in top, side and intermediate view orientations has a D6 point-group symmetry. It possesses the characteristic hexagonal bilayer (HBL) appearance. Each hexagonal half-molecule comprises size hollow globular substructures (HGS) presumed to correspond to the dodecameric subunits. In projection, when the molecule is viewed along its 6-fold axis, the two halves are not perfectly eclipsed. The vertices of the upper hexagonal layer are 14 degrees rotated clockwise compared with those of the lower half. At a threshold displaying 100% of the expected molecular volume, the 3D volume contains in its center a flat hexagonal central mass disconnected from the rest of the volume. Several types of connections, termed c1 through c4, are visible between the HGSs. The c1 and c2 connections link the HGSs of the same hexagonal half-molecule. The c3 connections make a hexagonal inner bracelet linking the HGSs of each half-molecule. The c4 connections link pairs of HGSs superposed in the two hexagonal layers. Because of the half-molecules rotation around the 6-fold axis, the two HGSs linked by a c4 connection are not exactly superposed. It is proposed that the c3 and c4-connection bodies and less probably the flat central hexagonal mass are composed of chloroheme-deficient linker chains. When eroding the 3D volume by raising the threshold, the HGS appears composed of three elongated structures likely containing four globin chains. In addition, they show an approximate 3-fold symmetry. At high thresholds, two of these masses, dumbbell-shaped, separate into globular masses while the third structure remains compact as long as 1% of the molecular volume is displayed.

Animals↗
PubMed1996

Glycosylated threonine but not 4-hydroxyproline dominates the triple helix stabilizing positions in the sequence of a hydrothermal vent worm cuticle collagen.

The cuticle collagen of the vestimentiferan Riftia pachyptila, an organism which is endemic to deep-sea hydrothermal vents, has several unusual properties including an extraordinary length (1.5 microns), a high thermal stability (37 degrees C) in spite of a low 4-hydroxyproline content and an atypically high threonine content (20 mol%). We have now purified the constituent chain of cuticle collagen and show that it contains about 40% carbohydrate, which is mainly galactose, indicating that the chain has a molecular mass of approximately 750 kDa. Several large (30 to 150 kDa) fragments, which all contained carbohydrate, could be produced by cleavage with endoproteinase Lys-C, bacterial collagenase and cyanogen bromide (CNBr). Edman degradation of these and several smaller fragments was used to determine about 3000 sequence positions comprising 60% of the total triple-helical sequence. This demonstrated mainly typical Gly-X-Y triplet repeats with a few imperfections and a longer N-terminal non-triplet sequence. Most of the 4-hydroxyproline was found in triplet position X, where it decreases the stability of the triple helix. About 40% of the Y positions could not be identified, which correlated with a low abundance of threonine in the sequence and the demonstration of threonine in these positions after deglycosylation of several peptides by treatment with hydrofluoric acid. Matrix-assisted laser desorption ionisation mass spectrometry of selected peptides indicated that the blocked threonine residues are occupied by chains of one, two or three hexoses (presumably galactose). These glycosylated threonine residues in Y positions are therefore likely to replace 4-hydroxyproline as the major contributor to triple helix stabilization. Studies with a synthetic (Gly-Pro-Thr)10 oligopeptide demonstrated a low thermal stability of its triple helix which emphasizes a crucial role of glycosylation for stabilization.

Amino Acid Sequence↗
PubMed1996

Three-dimensional reconstruction by cryoelectron microscopy of the giant hemoglobin of the polychaete worm Alvinella pompejana.

A frozen-hydrated specimen of the hexagonal bilayer hemoglobin (HBL Hb) from the deep-sea hydrothermal vent polychaete worm Alvinella pompejana, the most thermophilic metazoan known to date, was observed in the electron microscope and subjected to three-dimensional (3D) reconstruction by the method of random conical tilt series. At a resolution of 34.6 A by the differential phase residual method and 27.7 A by the Fourier shell correlation method, the 3D volume possesses a D6 point-group symmetry. While in previous 3D reconstructions of annelid and vestimentiferan Hbs the vertices of the upper layer were 16 degrees rotated compared with those of the lower layer, in Alvinella Hb the vertices of the two hexagonal layers are almost perfectly eclipsed when viewed along the 6-fold axis. As in the HBL Hbs of Riftia pachyptila and Macrobdella decora, a central linker complex is decorated by 12 hollow globular substructures (HGS). The linker complex comprises (1) a central hexagonal toroid, (2) two internal bracelets onto which the HGSs are built, and (3) six connections between the two hexagonal layers. Each HGS is composed of six masses, which are separated when the volume is displayed at high threshold, plus one additional mass involved in the bracelet connecting the six HGSs in both hexagonal layers. The HGSs have a local pseudo 3-fold symmetry and a disposition of the high-density masses different from those of Riftia V1 Hb.

Animals↗
PubMed2001

Occurrence of two architectural types of hexagonal bilayer hemoglobin in annelids: comparison of 3D reconstruction volumes of Arenicola marina and Lumbricus terrestris hemoglobins.

A 3D reconstruction at 25 A resolution of native hemoglobin of the polychaete worm Arenicola marina was carried out from frozen-hydrated specimens examined in the electron microscope. The reconstruction volume of this large extracellular multimeric respiratory pigment appears as a hexagonal bilayer structure with eclipsed vertices in its upper and lower hexagonal layers. Conversely, in hemoglobins of oligochaetes, achaetes, and vestimentiferans and in chlorocruorins of the Sabellidae (polychaete) family, the vertices of the upper layer are 16 degrees clockwise rotated with respect to those of the lower layer. The fact that two other polychaete hemoglobins (Alvinella pompejana and Tylorrhynchus heterochaetus) have the same architecture as Arenicola led us to define two types of hexagonal bilayer hemoglobins/chlorocruorins: (i) type-I present in oligochaete, achaete, and vestimentiferan hemoglobins and in Sabellidae chlorocruorins; and (ii) type-II present in polychaete hemoglobins. A comparative study of the hemoglobins of Lumbricus terrestris (type-I) and Arenicola marina (type-II) showed that only two small differences located in the c4 and c5 linking units are responsible of the important architectural difference present in oligomers. A likely scheme proposed to explain the phylogenic distribution of the two types suggests that Clitellata, Sabellida (polychaete), and vestimentiferan hemoglobins and chlorocruorins derive from a type-I ancestral molecule, while Terebellida (Alvinella), Phyllodocida (Tylorrhynchus), and Scolecida (Arenicola) and possibly other polychaetes derive from an ancestor molecule with type-II hemoglobin. The architectures of the hollow globular substructures are highly similar in Arenicola and Lumbricus hemoglobins, with 12 globin chains and three linking units (c3a, c3b, and c4). The central piece of Arenicola hemoglobin is an ellipsoid while that of Lumbricus is a toroid. No phylogenic correlation could be found between the structure of the central pieces and the architecture type.

Animals↗
PubMed2000

Molecular adaptation to an extreme environment: origin of the thermal stability of the pompeii worm collagen.

The annelid Alvinella pompejana is probably the most heat-tolerant metazoan organism known. Previous results have shown that the level of thermal stability of its interstitial collagen is significantly greater than that of coastal annelids and of vent organisms, such as the vestimentiferan Riftia pachyptila, living in colder parts of the deep-sea hydrothermal environment. In order to investigate the molecular basis of this thermal behavior, we cloned and sequenced a large cDNA molecule coding the fibrillar collagen of Alvinella, including one half of the helical domain and the entire C-propeptide domain. For comparison, we also cloned the 3' part of the homologous cDNA from Riftia. Comparison of the corresponding helical domains of these two species, together with that of the previously sequenced domain of the coastal lugworm Arenicola marina, showed that the increase in proline content and in the number of stabilizing triplets correlate with the outstanding thermostability of the interstitial collagen of A. pompejana. Phylogenetic analysis showed that triple helical and the C-propeptide parts of the same collagen molecule evolve at different rates, in favor of an adaptive mechanism at the molecular level.

Adaptation, Physiological↗
PubMed2001

Observation of large, non-covalent globin subassemblies in the approximately 3600 kDa hexagonal bilayer hemoglobins by electrospray ionization time-of-flight mass spectrometry.

A non-covalent globin subassembly comprising 12 globin chains (204 to 214 kDa) was observed directly by electrospray ionization time-of-flight mass spectrometry in the native hexagonal bilayer hemoglobins from the oligochaetes Lumbricus terrestris and Tubifex tubifex, the polychaetes Tylorrhynchus heterochaetus, Arenicola marina, Amphitrite ornata and Alvinella pompejana, the leeches Macrobdella decora, Haemopis grandis and Nephelopsis oscura and the chlorocruorin from the polychaete Myxicola infundibulum, over the pH range 3.5-7.0. The Hb from the deep-sea polychaete Alvinella exhibited in addition, peaks at approximately 107 kDa and at approximately 285 kDa, which were assigned to subassemblies of six globin chains and of 12 globin chains with three non-globin linker chains, respectively. The experimental masses decreased slightly with increased de-clustering potential (60 to 160 V) and were generally 0.1 to 0.2 % higher than the calculated masses, due probably to complexation with cations and water molecules.

Animals↗
PubMed1997

Diffraction contrast imaging of extracellular matrix components using zero-loss filtering.

The beta-chitin microfibrils from the deep-sea hydrothermal vent worm Riftia pachyptila were studied in both mature and fresh tubes experimentally obtained. The methods used were electron diffraction and electron diffraction contrast images, in conjunction with an electron-energy filter, operated in the zero-loss mode. In both studied samples, microfibrils are organized in successive layers, inside which they are parallel. However, the fresh tube is less densely packed and diffraction data show that these microfibrils may be in a partially hydrated state. These results indicate that a later step occurs in the compaction of the tube material once it has been extruded. Comparison of filtered and unfiltered diffraction patterns shows that zero-loss filtering significantly improves both working conditions and quality of diffraction recordings.

Actin Cytoskeleton↗
PubMed1999

A two-exposure technique for ice-embedded samples successfully reconstructs the chlorocruorin pigment of Sabella spallanzanii at 2. 1 Nm resolution.

A technique for reconstructing ice-embedded macromolecules from electron micrographs taken at two specimen tilts (+/-23 degrees ) has been used to determine the structure of chlorocruorin isolated from the Polychaete annelid Sabella spallanzanii. Images of individual molecules were extracted in couples from two micrographs of the same field of view so each couple consists of two projections of the same molecule. One couple was used as a fixed reference for alignment. Different references yielded reconstructions with different orientations. These were merged to give a model against which the orientation of 1624 first-exposure images was refined to give a final reconstruction at 2.1 nm resolution. The structure of this hematic pigment, essentially the same as that for Lumbricus terrestris, is a bilayer structure with overall symmetry D6, containing six hollow groups per layer. A hollow group is formed by six globular masses and has approximate threefold symmetry. Other structural elements connect the two layers and the hollow groups in a layer. This non-globin material occupies about 15% of the total molecular volume. The results show that the double-exposure strategy, previously described by some of the authors and tested in computer simulations, performs well in real experiments and could be used to obtain preliminary reconstructions in a semiautomatic way.

Animals↗
PubMed1997

A survey of homeobox genes in Chaetopterus variopedatus and analysis of polychaete homeodomains.

A survey of genomic DNA from the polychaete Chaetopterus variopedatus was conducted using the polymerase chain reaction. Twelve unique homeobox-containing gene fragments were recovered. Phylogenetic analysis indicates that seven of the fragments are from genes belonging to Hox homeobox classes. Other fragments show orthology with Xlox, caudal, and Prh homeobox classes, with two fragments not definitely assignable to a homeobox class by our analysis. Orthology with gene sequences reported for the polychaete Ctenodrilus serratus, by Dick and Buss (1994), was calculated and indicated that at least eight of the C. variopedatus fragments are homologous to these previously reported sequences. Tabulation of the Hox gene relationships suggest that polychaetes have representative genes of each of the Hox cognate groups except Abd-B. This conclusion further suggests that the Hox cluster in the basal protostome ancestor had already undergone the gene duplications leading to the complete complement of homeotic genes known in Drosophila, with the possible loss of Abd-B in the polychaete lineage.

Amino Acid Sequence↗
PubMed2000

Phylogenetic analysis of Tubificidae (Annelida, Clitellata) based on 18S rDNA sequences.

Tubificids are aquatic clitellate worms, but recent analyses of morphological characters suggested that this family, as currently recognized, is paraphyletic. Sequences of the 18S rDNA gene of 40 protostome worm species (including 13 representatives of the Tubificidae) and 2 mollusc species were cladistically analyzed to test the monophyly of the Tubificidae and that of some of its constituent subfamilies. Under all alignments tested, the same general phylogenetic pattern emerged. The data support the idea that the Naididae, another clitellate taxon, is associated with some "rhyacodriline" groups within the Tubificidae. The data also corroborate the idea that the Tubificinae and the Limnodriloidinae are monophyletic but indicate that the Rhyacodrilinae and the Phallodrilinae are not. Bathydrilus does not appear to be closely related to other "phallodriline" genera.

Animals↗
PubMed1993

Purification and characterization of recombinant polymeric hemoglobin P1 of Glycera dibranchiata.

The apoprotein of component P1 of the polymeric fraction of the intracellular hemoglobin of the marine polychaete Glycera dibranchiata has been expressed at a high level in Escherichia coli. The expressed globin was reconstituted with heme and purified. The N-terminal sequence of the recombinant P1 is identical to the cDNA-derived sequence of cloned P1 (Zafar et al., Biochem. Biophys. Acta, 1041, 117-123, 1990). Gel filtration, SDS-PAGE, optical spectra over the range 200-650 nm, and circular dichroism over the range 200-250 nm of the purified recombinant P1 were very similar to the polymeric fraction of native Glycera hemoglobin. The molar ellipticity at 222 nm provided an estimate of 77% for the alpha-helical content of the recombinant P1, in excellent agreement with that calculated from the crystal structure of Glycera monomeric component M-II. Although the oxygen binding affinity of the recombinant P1 is higher than that of the polymeric fraction of Glycera hemoglobin (3-4 torr vs 7-13 torr), which consists of at least six different single-chain hemoglobins, the Hill coefficient is lower (1.0-1.2 vs 1.2-1.4).

Animals↗