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1.
Balaenoptera omurai, formerly classified as a small form of Bryde's whale, was recently reclassified as a new baleen whale species of the family Balaenopteridae. Although researchers have investigated the evolutionary history of Balaenopteridae and their relatives using molecular phylogenetic methods, the taxonomy of the ordinary Bryde's whale (Balaenoptera brydei) and small-form Bryde's whales (Balaenoptera edeni and B. omurai) remains unclear. We have used complete mtDNA sequences and short interspersed repetitive element (SINE) insertion patterns to construct the evolutionary history of both B. omurai and the taxonomically redefined species, B. edeni. The combined results demonstrate that B. omurai forms a monophyletic lineage with B. musculus, B. brydei, B. edeni and B. borealis and that B. omurai and B. musculus successively diverged from their common ancestor. In addition, we also showed that B. edeni constitutes a sister taxon to B. brydei. Our data suggest that B. omurai evolved as an ancient independent lineage that diverged much earlier than B. borealis, B. brydei and B. edeni, which were previously believed to be closely related to B. omurai.  相似文献   

2.
As demonstrates the investigation of the blood system in the whale (Balaenoptera edeni) performed by means of the macropreparation of corrosive casts and sawcuts, in this species, as in other Cetacea, there is a well developed complex of the arterial rete mirabile, owing to which the brain is supplied with blood. In the whale mentioned this complex is comparable with that in dolphins and is noticeably less developed than in the spermacet (Physeter sp.). Angioarchitectonic of the whale has much in common with the arterial system of representatives of Balaenopteridae family, previously studied.  相似文献   

3.
Bryde's-like whales are a complex of medium-sized baleen whales that occur in tropical waters of all three major ocean basins. Currently, a single species of Bryde's whale, Balaenoptera edeni Anderson, 1879, is recognized, with two subspecies, Eden's whale, B. edeni edeni and Bryde's whale, B. edeni brydei (Olsen, 1913), although some authors have recognized these as separate species. Recently, a new, evolutionarily divergent lineage of Bryde's-like whale was identified based on genetic data and was found to be restricted primarily to the northern Gulf of Mexico (GOMx). Here, we provide the first morphological examination of a complete skull from these whales and identify diagnostic characters that distinguish it from the other medium-sized baleen whale taxa. In addition, we have increased the number of genetic samples of these Bryde's-like whales in the GOMx from 23 to 36 individuals, all of which matched the GOMx lineage. A review of Bryde's-like whale records in the Caribbean and greater Atlantic supports an isolated distribution for this unique lineage, augmenting the genetic and morphological body of evidence supporting the existence of an undescribed species of Balaenoptera from the Gulf of Mexico.  相似文献   

4.
布氏鲸(Bryde’s whale)是广泛分布于温带和热带海域的一类中等体型须鲸,通常认为存在小布氏鲸(Balaenoptera edeni edeni)和布氏鲸(B. e. brydei)两个亚种。然而,有研究表明它们应该被划分为两个独立物种,即近岸小型布氏鲸(B. edeni)和远洋大型布氏鲸(B. brydei)。由于两者外部形态极其相似,并且存在同域分布现象,很难基于外观进行准确的物种鉴定。近年来,广西北部湾涠洲岛海域出现一个稳定的布氏鲸栖息种群,但目前尚不清楚属于哪种布氏鲸。研究采集了涠洲岛布氏鲸种群中两个体的粪便样品,从其中一份样品成功提取基因组DNA,并基于线粒体Cyt b和COΙ基因序列开展物种鉴定和遗传分析,鉴定结果为小布氏鲸。此外,还鉴定出涠洲岛海域同年死亡的一头须鲸也为小布氏鲸。据此推测涠洲岛水域栖息的布氏鲸种群可能是小布氏鲸。研究首次基于粪便样品,采用分子生物学技术,成功开展了活体布氏鲸的物种鉴定。这种基于非损伤采样的物种鉴定方法值得进一步优化并推广应用。  相似文献   

5.
A relaxin-like molecule has been isolated from the ovaries of the spiny dogfish (Squalus acanthias) which consists, like porcine relaxin, of two chains linked by the insulin-type disulfide bonds. The total number of amino acids is 54 of which 24 are in the A chain and 30 in the B chain. The molecular masses, calculated from the amino acid compositions, are 2510 Da for the A chain and 3370 Da for the B chain, making a total of 5880 Da. The N-terminus of the B chain is protected by a 5-oxoproline (pyrrolidone carboxylic acid) residue which is also found in the same position in the relaxins of sand tiger shark, pig, and man, whereas the relaxin of the rat has its 5-oxoproline residue at the N-terminal of the A chain. By all available criteria, S. acanthias relaxin is a typical member of the relaxin family although the sequence homology to mammalian relaxins is limited to about 45% of its amino acid residues. In contrast, the dogfish relaxin shows about 80% homology with sand tiger shark relaxin (the first such interspecies similarity to be observed) and has about twice the biological activity (mouse pubic symphysis test) when compared to sand tiger relaxin.  相似文献   

6.
In addition to B31 (CM-a) and B28 (CM-B) relaxins, acid-acetone extracts of ovaries of pregnant sows contain a third major relaxin species (relaxin C). The major components of relaxin C possess about half the activity of CM-a or CM-B in the guinea pig palpation assay, but are completely inactive in the mouse pubic ligament assay. Its uterotrophic and protein anabolic effects in ovariectomized, estrogen-primed mice, however, are comparable to those of CM-B. Sequence analysis indicates that the two major components of relaxin C, like the other porcine relaxins, consist of two polypeptide chains linked by disulfide bonds. The shorter (A) chains are identical to the A chains of the other porcine relaxins, except for the absence of the N-terminal arginine residue. The B chains display microheterogeneity; the B sequences of the two predominant species are the same as those of the other porcine relaxins through B25, but terminate at valine residue B25 or serine residue B26, respectively.  相似文献   

7.
We determined the myoglobin (Mb) cDNA sequences of nine cetaceans, of which six are the first reports of Mb sequences: sei whale (Balaenoptera borealis), Bryde's whale (Balaenoptera edeni), pygmy sperm whale (Kogia breviceps), Stejneger's beaked whale (Mesoplodon stejnegeri), Longman's beaked whale (Indopacetus pacificus), and melon-headed whale (Peponocephala electra), and three confirm the previously determined chemical amino acid sequences: sperm whale (Physeter macrocephalus), common minke whale (Balaenoptera acutorostrata) and pantropical spotted dolphin (Stenella attenuata). We found two types of Mb in the skeletal muscle of pantropical spotted dolphin: Mb I with the same amino acid sequence as that deposited in the protein database, and Mb II, which differs at two amino acid residues compared with Mb I. Using an alignment of the amino acid or cDNA sequences of cetacean Mb, we constructed a phylogenetic tree by the NJ method. Clustering of cetacean Mb amino acid and cDNA sequences essentially follows the classical taxonomy of cetaceans, suggesting that Mb sequence data is valid for classification of cetaceans at least to the family level.  相似文献   

8.
Relaxin     
1. Relaxin is a hormone of reproduction that appears to affect parturition, uterine accommodation, and sperm motility to varying degrees in many species. 2. All relaxins have the same two chain, disulfide-linked insulin-like structure and two arginine residues in the midregion of the B chain. 3. The active relaxin molecule is produced by excision of a connecting peptide from the prohormone. 4. The biosynthetic pathways of insulin and relaxin are alike, but the relaxin prohormone is about twice as large as the corresponding proinsulin. 5. The primary structures of relaxins from apparently closely related species differ significantly in their amino acid compositions and do not fit into the traditional scheme of molecular evolution.  相似文献   

9.
Abstract: Vocalizations were recorded from a captive juvenile Bryde's whale, Balaenoptera edeni , that stranded off the gulf coast of Florida (Pinellas Co.) and was held at Sea World of Florida. The most common vocalization was a pulsed moan with durations of 0.5–51 set and acoustic energy from 200–900 Ht. Although these sounds are unlike any reported previously from this species, there are similarities to moans recorded opportunistically during a feeding study of free-ranging B. edeni in the Gulf of California (GOC). The pulsed moans recorded from Bryde's whale adults in the GOC were shorter in duration (0.7–1.4 set) than those recorded from the captive juvenile, but the frequencies were similar (165–875 Hz). In addition, a series of discrete, regularly spaced pulses (interpulse interval = 0.5–1.0 set, 700–950 Hz) were recorded only in the presence of Bryde's whale calves in the GOC.
Pulse rates produced by the captive juvenile (20–70 pulses/set) were intermediate between those recorded in the presence of GOC adults (60–130/sec) and calves (10–20/set). With these limited data it is not possible to determine to what extent the intermediate qualities of the juvenile call reflect maturational differences in the sound production apparatus, a phase of learning to vocalize like an adult, or the characteristics of a context-dependent call not recorded in the GOC.  相似文献   

10.
In the Pacific common minke whale (Balaenoptera acutorostrata ), a new variant of Brucella has been detected using the polymerase chain reaction. Detailed analysis of the porin protein genes, omp2a and omp2b from the whale Brucella showed that these two genes have some motifs in common with Atlantic marine strains in the 5'-terminal one-third region. On the other hand, the nucleotide sequences in the 3'-terminal two-thirds region of the two genes were almost identical to the respective genes of terrestrial strains. Thus, Pacific whale Brucella omp2 genes are chimeras between marine and terrestrial strains.  相似文献   

11.
Recent structure/function studies on human relaxin II have led to the conclusion that the arginines B13 and/or B17 are important for biological activity. These studies have been confirmed and extended with the help of chemically synthesized derivatives, i.e. dicitrulline (B13, B17), two monocitrulline (B13 and B17), a dilysine (B13, 17), and alanine (B17) relaxins. The CD spectra of synthetic human relaxin and of the derivatives are indistinguishable. Yet, only the native human relaxin II is biologically active and binds strongly to relaxin receptor preparations in vitro. The inactivation is strictly due to side chain functions, in particular the replacement of either or both arginines in the positions B13 or B17. Binding is mediated by a two-prong electrostatic and hydrogen-binding interaction via arginines B13 and B17. Neither B13 nor B17 alone are sufficient and a positive charge equidistant from the B chain helix is equally insufficient. This binding mechanism appears to be unique, as concerns hormone receptor interaction.  相似文献   

12.
A Bryde's whale, Balaenoptera edeni , was rescued after having been entrapped in the Manning River, Australia, for 100 d. Blood, skin, and epidermal tissue were analyzed to determine the whale's taxonomic status, gender, and health. This paper reports the results of these analyses and discusses the findings in relation to the potential physiological damage to the whale from its protracted stay in the river. Molecular genetic analysis of epidermal tissue identified the whale as a male of the rare pygmy form of Bryde's whale. The 10.3-m whale was diagnosed as emaciated, parasitized, under stress, and in a state of profound catabolism at the time of its rescue. Although it had greatly depleted its energy reserves, the whale was rescued from the river before the onset of ill health or irreparable physiological damage. No organ dysfunction was evident with the possible exception of some deterioration in kidney function most likely caused by parasitism. The whale swam away srongly on release, and its chances of survival appeared to be good.  相似文献   

13.
The functional properties of haemoglobin from the Mediterranean whale Balaenoptera physalus have been studied as functions of heterotropic effector concentration and temperature. Particular attention has been given to the effect of carbon dioxide and lactate since the animal is specialised for prolonged dives often in cold water. The molecular basis of the functional behaviour and in particular of the weak interaction with 2,3-diphosphoglycerate is discussed in the light of the primary structure and of computer modelling. On these bases, it is suggested that the A2 (Pro-->Ala) substitution observed in the beta chains of whale haemoglobin may be responsible for the displacement of the A helix known to be a key structural feature in haemoglobins that display an altered interaction with 2,3-diphosphoglycerate as compared with human haemoglobin. The functional and structural results, discussed in the light of a previous study on the haemoglobin from the Arctic whale Balaenoptera acutorostrata, give further insights into the regulatory mechanisms of the interactive effects of temperature, carbon dioxide and lactate.  相似文献   

14.
The cumulus-oocyte-complexes (COCs) recovery rates with respect to reproductive status per sei (Balaenoptera borealis) and Bryde's (B. edeni) whales were determined in Experiment 1. The number of COCs recovered ranged from 16.0 to 30.6 and from 6.7 to 26.8 per sei and Bryde's whales, respectively. The effects of COCs grades and protein supplementation in embryo culture medium on development of in vitro fertilized (IVF) embryos were evaluated in sei and Bryde's whales in Experiment 2. The COCs were classified into either Grade A (COCs with five or more layers of compact cumulus cells) or Grade B (COCs with less than five layers of compact or expanded cumulus cells) before being cultured for IVM. The cleavage (12.0 to 19.5%), 4-cell (8.0 to 12.0%) and 8-cell (4.0 to 8.0%) formation rates in sei whales did not vary significantly between embryos derived from either grade A or B oocytes and between embryos cultured in either fetal whale serum (FWS)- or bovine serum albumin (BSA)-supplemented medium. The cleavage (4.0 to 14.8%), 4-cell (0.0 to 7.5%) and 8-cell (0.0 to 2.6%) formation rates in Bryde's whales did not vary significantly between embryos derived from either grade A or B oocytes and between embryos cultured in either FWS- or BSA-supplemented medium. The grade B oocytes cultured in FWS-supplemented medium developed to morula stage (1.1%) in sei whales. In conclusion, the present study indicates that IVF in sei whales is possible to achieve cleaved embryos developing to morula stage. This is the first in vitro embryo production attempt in sei and Bryde's whales.  相似文献   

15.
The complete amino acid sequence of the major component myoglobin from finback whale, Balaenoptera physalus, was determined by the automated Edman degradation of several large peptides obtained by specific cleavages of the protein. Three easily separable peptides were obtained by cleaving with cyanogen bromide at the two methionine residues and one large peptide was isolated after cleavage with (2-p-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine. More than 60% of the covalent structure was established by the sequential degradation of three of these peptides and the apomyoglobin. An additional 30% of the primary sequence was established with peptides obtained from tryptic digestion of both the apomyoglobin and the acetimidoapomyoglobin, and the final 10% of the sequence was completed after digestion of the two larger cyanogen bromide peptides with S. aureus strain V8 protease. This myoglobin differs from that of the sperm whale, Physeter catodon, at 15 positions, from that of the arctic minke whale, Balaenoptera acutorostrata, at 3 positions, and from that of the California gray whale, Eschrichtius gibbosus, at 4 positions. All of the substitutions observed in this sequence fit easily into the three-dimensional structure of the sperm whale myoglobin.  相似文献   

16.
To test the hypothesis that relaxin may play a role in the fetal abnormalities associated with pregnancy in type 1 diabetic women, we previously compared gestational relaxin concentrations in diabetic and clinically normal women using a porcine relaxin radioimmunoassay (RIA): Serum immunoactive relaxin was significantly (P < 0.001) elevated in the diabetic women. To confirm and extend this work in a larger group of subjects, we have now used an enzyme-linked immunosorbent assay (ELISA) specific for human H2 relaxin (the normal human gene product) to determine immunoactive serum relaxin concentrations in serial samples from 61 Type 1 diabetic and 21 normal pregnant women. Samples from 22 of the diabetic and nine of the normal women were also directly compared in the porcine relaxin RIA. ELISA-determined serum relaxin was higher (P < 0.001) at 24 and 36 weeks of pregnancy in type 1 diabetic women than in controls, confirming previous findings. However, the geometric mean increase in immunoactive relaxin concentration in identical samples from pregnant diabetic women over that of controls was significantly greater with the RIA than with the ELISA (271% vs 44%; P < 0.001). To investigate this discrepancy, the specificity and epitope selectivity of the RIA and the ELISA were compared using several synthetic polypeptides, including human relaxins H1 and H2, and relaxin and insulin derivatives. Both assays showed great specificity, but the porcine RIA selectively identified the epitopes of the receptor-binding domain of the relaxin B chain and cross-reacted strongly with H1 and H2 relaxins. In contrast, only the H2 peptide was detected by the ELISA antiserum. Therefore, the marked discrepancy between the RIA and the ELISA could be due to the presence in the diabetic samples of another relaxin-like molecule in addition to the normal H2 relaxin. The biological consequences of elevated serum relaxin in diabetic pregnancy remain to be elucidated.  相似文献   

17.
In humans, the relaxin hormone family includes H1, H2 and H3 isoforms and insulin-like peptides 3 to 6. The ever-increasing interest in relaxin as potential new drug requires reliable methods to compare bioactivity of different relaxins. The existing bioassays include in vivo or ex vivo methods evaluating the organ-specific responses to relaxin and in vitro methods based on measurement of cAMP increase in relaxin receptor-bearing cells. We previously demonstrated that relaxin dose-dependently inhibits platelet aggregation. On this basis, we have developed a simple, reliable bioassay for relaxin used to compare purified porcine relaxin, assumed as reference standard, with two recombinant human H2 relaxins, H3 relaxin, insulin-like peptides 3 and 5. Pre-incubation of platelets with relaxins (3, 10, 30,100, 300 ng/ml; 10 min.) caused the inhibition of ADP-induced platelet aggregation. Within the 10-100 ng/ml range, porcine relaxin showed the highest effects and a nearly linear dose-response correlation. Lower peptide concentrations were ineffective, as were insulin-like peptides 3 and 5 at any concentration assayed. Platelet inhibition was mediated by specific RXFP1 relaxin receptor and cGMP, whose intracellular levels dose-dependently increased upon relaxin. For comparison, we stimulated THP-1 cells, a relaxin receptor-bearing cell line, with porcine relaxin, human H2 and H3 relaxins at the above concentrations (15 min.). We observed a dose-related increase of intracellular cAMP similar to the trend of platelet inhibition. Insulin like peptide 5 was ineffective. In conclusion, this study shows that inhibition of platelet aggregation may be used to assess bioactivity of relaxin preparations for experimental and clinical purposes.  相似文献   

18.
Active acoustic techniques can be used to detect whales. The ability to detect whales from a moving vessel or stationary buoy could reduce conflicts between hazardous human activities and whales, enabling implementation of mitigation procedures. In order to identify acoustic targets correctly as whales, knowledge of whale target strength (TS) is required. Active acoustic detections of fin whales (Balaenoptera physalus) were made in the Norwegian Sea; acoustic data were collected using calibrated omnidirectional sonar, operating at a discrete frequency of 110 kHz. Three fin whales of similar size (estimated between 16 and 18 m total length) had an overall average TS for all insonified body aspects of ?11.4 dB [95% CI ?12.05, ?10.8] at 110 kHz, with a total spread of nearly 14 dB. As expected, the received signals were stronger when the fin whales were insonified at broadside (?5.6 dB). Individual fin whale TS varied by approximately 12 dB, probably due to variation in lung volume with breathing, and to dynamic swimming kinematics. Our TS values are consistent with values reported previously for other large whales. All data together pave the way for development of automated acoustic whale detection protocols that could aid whale conservation.  相似文献   

19.
E E Büllesbach  C Schwabe 《Biochemistry》1985,24(26):7717-7722
Porcine ovaries were collected from pregnant sows under conditions designed to keep autolysis to an absolute minimum. During the extraction the tissues were never allowed to warm up to 0 degree C until submerged in 1.6 N HCl. Isolation and fractionation of the various relaxin forms became possible by application of CM-cellulose chromatography at pH 5.5 and 7.8, gel filtration, and high-performance liquid chromatography. The new isolation procedure has made it possible to isolate and identify LeuB32 relaxin. Also, [Leu-PheA0]B29 relaxin was identified and the existence of a [Leu-PheA0]B32 relaxin may be deduced from our data. Controlled digestion of B-chain-extended relaxins with carboxypeptidase A led to the large-scale production of homogeneous B29 relaxin, a suitable starting material for controlled chemical modification of porcine relaxin.  相似文献   

20.
E E Büllesbach  C Schwabe 《Biochemistry》1986,25(20):5998-6004
Porcine relaxins shortened at the N terminus of the A chain were produced after protection of all amino groups with the base-labile [[(methylsulfonyl)ethyl]oxy]carbonyl (Msc) protecting group. The first two amino acids were removed by cyanogen bromide digestion whereby simultaneously a free alpha-amino group was generated in position A3. The resulting des-ArgA1,MetA2-N epsilon A7,N epsilon A16,N epsilon B8-tris [[[(methylsulfonyl)ethyl]oxy]carbonyl]relaxin. was further shortened by preparative Edman degradation. The shortest derivative obtained was des-ArgA1,MetA2,ThrA3,LeuA4,SerA5,GluA6 -N epsilon A7,N epsilon A16,N epsilon B8-tris[[[(methylsulfonyl)ethyl]oxy]carbonyl]relaxin. The deprotection of the derivatives in alkaline media resulted in crude des-A(1-2)- to des-A(1-6)-relaxins, which were subsequently purified by gel filtration on Sephadex G-50 superfine followed by either ion exchange chromatography on CM-cellulose at pH 5.1 or high-performance liquid chromatography on reversed-phase columns. During the CNBr digest, a side product was isolated that was identified as the corresponding homoserine ( [HseA2]relaxin) derivative. Shortened relaxin derivatives and [HseA2]relaxin were characterized by reversed-phase chromatography, electrophoresis, end-group determination, and amino acid composition. Circular dichroism studies revealed a distinct change in the structure of relaxins that were shortened by three and more amino acid residues. In the mouse interpubic ligament assay, des-A(1-2)-relaxin and [HseA2]relaxin were fully biologically active while the bioactivity of des-A(1-3)-relaxin dropped to about 50%. Relaxins shortened by four and more amino acid residues were biologically inactive.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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