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1.
Presented a choice between conspecific males and 2 congeneric males, virgin females ofMelittobia australica andM. digitata chose conspecific males disproportionately more often, whereasM. femorata females distributed themselves evenly among the choices. Empty tubes, provided as the fourth choice in the test apparatus,
were entered much less often than tubes containing live males. Females of all species chose “wrong” males about equally frequently.
These observations suggest that even non-conspecific males possess some degree of attractiveness to virgin females. Chemicals
in the sex pheromone of the males are presumed to be the source of the males' attractancy. The incomplete species specificity
is interpreted in light of the life history of this genus, and it is suggested that specific recognition cues operate primarily
after the sexes come together.
Supported by a grant from Kagoshima Prefecture in Japan under the exchange program of faculty members between Kagoshima University
and the University of Georgia. 相似文献
2.
Junichi Ishihara Nagahiro Saijo Yasutsuna Sasaki Hidehiko Nakano Akira Ozaki Hidenobu Takahashi Masanori Sakurai Kazuhiko Nakagawa Masaaki Iigo Fumihiko Kanzawa Akio Hoshi Weon Seon Hong James R. Jett Terumi Takahashi 《Cancer immunology, immunotherapy : CII》1987,24(3):185-189
Summary The antitumor effect of recombinant human tumor necrosis factor (rH-TNF) on two clones of rat fibrosarcoma with different metastatic potential to lymph nodes was examined. The colony formation of clone A, which has high metastatic potential, was completely inhibited by continuous exposure to rH-TNF at 50 U/ml. In contrast, colony formation of clone G, which has low metastatic potential, was not inhibited by high concentrations of rH-TNF (10,000 U/ml). The inhibitory effect of rH-TNF on colony formation by clone A was also observed with a 1-h exposure to rH-TNF. This effect was time and concentration dependent, as determined by the colony assay, 3H-thymidine uptake assay, and 51Cr-release assay. 3H-thymidine and 3H-uridine uptake per cell of clone A exposed to rH-TNF was not decreased. This suggests that the mechanisms of the antitumor effect of rH-TNF were not due to inhibition of DNA and RNA synthesis of tumor cells. In vivo growth and lymph node metastases of clone A inoculated i.p. to Donryu strain rats were completely suppressed by 14 consecutive i.p. injections of 105 or 106 U/kg per day of rH-TNF. On the other hand the growth of clone G was not influenced by rH-TNF administration. 相似文献
3.
Mitochondrial DNA polymorphism in native Philippine cattle based on restriction endonuclease cleavage patterns 总被引:4,自引:0,他引:4
Tomomasa Watanabe Joseph S. Masangkay Shigeharu Wakana Naruya Saitou Takeshi Tomita 《Biochemical genetics》1989,27(7-8):431-438
An analysis of patterns of cleavage of mtDNA by restriction endonucleases was performed for nine individuals from the Philippine
population of native cattle. MtDNA polymorphisms were detected in the restriction patterns generated by the following six
enzymes,BamHI,BglII,EcoRV,HindIII,PstI, andScaI. The restriction patterns showing polymorphisms were distributed nonrandomly among the nine individuals examined from the
Philippine population of native cattle, indicating the existence of two separate types of mtDNA. These two types of mtDNA
are very different from each other, at the level of subspecies. Since the native Philippine cattle are considered to represent
an admixture of European and Indian cattle, the two types of mtDNA must be derived from the mtDNAs of both varieties. The
polymorphic sites in mtDNA have been located on a restriction map, and the nucleotide substitutions at some of the sites have
also been estimated. 相似文献
4.
Chuen-Shang C. Wu Junichi Hasegawa Andrew P. Smith Horace H. Loh Nancy M. Lee Jen Tsi Yang 《Journal of Protein Chemistry》1990,9(1):3-7
Based on circular dichroism (CD) and the sequence-predictive method, the opioid-binding cell adhesion molecule (OBCAM) consisted of one half -sheets and one fourth -helices. This is consistent with significant sequence homology of the protein to several members of the immunoglobulin (Ig) superfamily, particularly cell adhesion molecules, which are rich in -sheets. Hydropathy analysis suggests that hydrophobic and hydrophilic regions were evenly distributed along the sequence, but the NH2- and COOH-termini were hydrophobic. Hydrophobic moments and Fourier-transform amphipathic analyses further suggest that residues 23–30 and 83–93 were amphiphathie -sheets. The overall conformation of OBCAM was unaltered by adding linoleic acid, which is required for opioid ligand binding. 相似文献
5.
Promotive Effect of C18-Unsaturated Fatty Acids on the Abscission of Bean Petiole Explants 总被引:1,自引:0,他引:1
The abscission-promoting effects of C18-unsaturated fatty acidswere studied in bean (Phaseolus vulgaris L. cv. Masterpiece)petiole explants with the junction between the petiole and thepulvinus in the primary leaves in the light. Linolenic, linoleicand oleic acids promoted the abscission of the explants in thelight. Linolenic acid was the most effective among the compoundstested and its promotive effect was evident without any accompanyingincrease in the production of ethylene from the explants, ascompared with non-treated explants. Linolenic acid is easilyconverted to its hydroperoxide during the incubation with explants,as indicated by the formation of the conjugated diene and thegeneration of ethane. The production of ethylene from the explantstreated with linolenic acid was completely inhibited by theaddition of aminoethoxyvi-nylglycine (AVG), but large amountsof ethane were still generated. The promotive effect of linolenicacid was almost eliminated by the addition of scavengers offree radicals. Hydrogen peroxide and tert-butyl hydroperoxidepromoted abscission in the light. From these results, we concludedthat the abscission-promoting effect of linolenic acid are notmediated by the effect of ethylene but by the effect of itshydroperoxide, while the well-established pathway for the biosynthesisof ethylene from S-adenosylmethionine to ethylene, via 1-aminocyclopropane-l-carboxylicacid (ACC), was apparently operative. (Received May 1, 1991; Accepted July 10, 1991) 相似文献
6.
7.
S Harihara N Saitou M Hirai T Gojobori K S Park S Misawa S B Ellepola T Ishida K Omoto 《American journal of human genetics》1988,43(2):134-143
Mitochondrial DNA (mtDNA) polymorphisms were detected using 13 restriction enzymes on the total DNA obtained from blood samples of five Asian populations: Japanese and Ainu of northern Japan, Korean, Negrito (Aeta) of the Philippines, and Vedda of Sri Lanka. Of a total of 28 restriction-enzyme morphs detected, eight had not been reported previously. By combining the morphs, we were able to classify mtDNAs of 243 individuals into 20 mtDNA types. Phylogenetic analyses using maximum parsimony and genetic distance methods both showed that the Japanese, Ainu, and Korean populations were closely related to each other. Aeta was found to show a relatively close relationship to these three populations, confirming the conclusion from previous studies of blood markers. In contrast, Vedda was quite different from the other four populations. 相似文献
8.
Summary A mathematical theory for computing the probabilities of various nucleotide configurations among related species is developed, and the probability of obtaining the correct tree (topology) from nucleotide sequence data is evaluated using models of evolutionary trees that are close to the tree of mitochondrial DNAs from human, chimpanzee, gorilla, orangutan, and gibbon. Special attention is given to the number of nucleotides required to resolve the branching order among the three most closely related organisms (human, chimpanzee, and gorilla). If the extent of DNA divergence is close to that obtained by Brown et al. for mitochondrial DNA and if sequence data are available only for the three most closely related organisms, the number of nucleotides (m*) required to obtain the correct tree with a probability of 95% is about 4700. If sequence data for two outgroup species (orangutan and gibbon) are available, m* becomes about 2600–2700 when the transformed distance, distance-Wagner, maximum parsimony, or compatibility method is used. In the unweighted pair-group method, m* is not affected by the availability of data from outgroup species. When these five different tree-making methods, as well as Fitch and Margoliash's method, are applied to the mitochondrial DNA data (1834 bp) obtained by Brown et al. and by Hixson and Brown, they all give the same phylogenetic tree, in which human and chimpanzee are most closely related. However, the trees considered here are gene trees, and to obtain the correct species tree, sequence data for several independent loci must be used. 相似文献
9.
Methods for computing the standard errors of branching points in an evolutionary tree and their application to molecular data from humans and apes 总被引:23,自引:2,他引:21
Statistical methods for computing the standard errors of the branching
points of an evolutionary tree are developed. These methods are for the
unweighted pair-group method-determined (UPGMA) trees reconstructed from
molecular data such as amino acid sequences, nucleotide sequences,
restriction-sites data, and electrophoretic distances. They were applied to
data for the human, chimpanzee, gorilla, orangutan, and gibbon species.
Among the four different sets of data used, DNA sequences for an
895-nucleotide segment of mitochondrial DNA (Brown et al. 1982) gave the
most reliable tree, whereas electrophoretic data (Bruce and Ayala 1979)
gave the least reliable one. The DNA sequence data suggested that the
chimpanzee is the closest and that the gorilla is the next closest to the
human species. The orangutan and gibbon are more distantly related to man
than is the gorilla. This topology of the tree is in agreement with that
for the tree obtained from chromosomal studies and DNA-hybridization
experiments. However, the difference between the branching point for the
human and the chimpanzee species and that for the gorilla species and the
human-chimpanzee group is not statistically significant. In addition to
this analysis, various factors that affect the accuracy of an estimated
tree are discussed.
相似文献
10.
On the delta Q-test of Templeton 总被引:1,自引:0,他引:1
N Saitou 《Molecular biology and evolution》1986,3(3):282-284