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1.
Immunoblot analysis using a monoclonal antibody specific tophytochrome B (phyB) suggest that this protein is undetectablein the hy3 mutant of Arabidopsis. Photophysiological experimentsrevealed that hy3 mutants do not display end-of-day far-redgrowth responses. Thus, this particular phytochrome responseseems to be mediated in large part by phyB. (Received September 20, 1991; Accepted September 26, 1991)  相似文献   

2.
A new, stygobiont species of Hauffenia (Pollonera, 1898) fromnortheastern Austria is described. It has been previously misidentifiedas H. kerschneri (Zimmermann, 1930), but detailed anatomicalinvestigations indicate that it is a separate species. Distinguishingcharacters are the very reduced peg of the operculum, a hypobranchialgland, an anterior lobe of the digestive gland in 25% of thespecimens, and an upright penial stylet. Some animals were infestedwith sporocysts and rediae. (Received 13 September 1991; accepted 1 November 1991)  相似文献   

3.
4.
The frxC gene, found in liverwort chloroplast DNA, encodes aprotein of unknown function. The deduced amino acid sequenceof the protein shows significant homology to that of ni-trogenaseFe-protein encoded by the nifH gene. We have cloned the frxCand nifH genes from the nitrogen-fixing cyanobacterium Plectonemaboryanum, using frxC- and nifH-specific probes, and have determinedtheir nucleotide sequences. The amino acid sequence deducedfrom the frxC gene of P. boryanum exhibits 83% homology to thatof the protein encoded by the/rxCgene from liverwort, whereasit exhibits only 34% homology to that encoded by the nifH genefrom the same organism, namely, P. boryanum. Northern blot analysisshowed that the frxC gene was transcribed more actively undernitrogenase-repressed conditions than under nitrogenase-inducedconditions, suggesting that the FrxC protein has a functiondistinct from nitrogen fixation. These results, together withthe phylogenetic relationship between the nifH and frxC genes,indicate that the frxC and nifH genes are derived from a commonancestral gene but have evolved independently to encode proteinswith different functions. (Received April 27, 1991; Accepted August 12, 1991)  相似文献   

5.
Isopentenyladenosine and cis-zeatin riboside have been identifiedby GC-MS from the tRNA of a red alga Porphyra perforata. (Received March 12, 1991; Accepted December 7, 1991)  相似文献   

6.
Five species of the marine pulmonate genus Smeagol (family Smeagolidae)are described from upper littoral shingle habitats from southeastern Australia and New Zealand. The systematic position ofthe family is discussed. (Received 24 June 1991; accepted 2 October 1991)  相似文献   

7.
Five cDNAs of auxin-regulated genes were isolated from mungbean (Vigna radiata) hypocotyl sections by differential hybridizationscreening. They were related to the soybean genes, Aux22 [Ainleyet al. (1988) J. Biol. Chem. 263: 10658] and SAUR [McClure etal. (1989) Plant Cell 1: 229]. Regulation of expression of thesegenes, examined by Northern blot analysis, appeared similarto that reported in soybean hypocotyls. (Received August 10, 1991; Accepted October 14, 1991)  相似文献   

8.
Runcinella thompsoni new species (Gastropoda: Opisthobranchia)is described on the basis of material collected in the GalapagosIslands. This new species differs from R. zelandica Odhner,1924, both in colour, reddish in the former, dark green withwhite freckles in the latter, and radular tooth morphology,mainly the first lateral teeth. The species is also comparedwith other red runcinids both from Atlantic and Pacific localities. (Received 28 October 1991; accepted 4 January 1993)  相似文献   

9.
A new species of Haminaea from the Southern Iberian Peninsulais described. Haminaea templadoi is characterized by the presenceof a penis with an apical semispherical crest provided by tensmall transverse folds and a well developed lateral lobe. Theshell has a sculptured surface with growth lines crossed bysmall transverse folds. (Received 20 October 1990; accepted 24 January 1991)  相似文献   

10.
A lectin was purified from the bark of Robinia pseudoacaciaby sequential ion-exchange chromatography on DEAE-Sepharoseand CM-Toyopearl. The purified lectin was estimated to havea molecular weight of 106 kDa and to be a homotetramer of subunitswith a molecular weight of 29 kDa. Antibodies raised againstthe bark lectin cross-reacted with a 29-kDa polypeptide duringWestern blot analysis, showing that the antibodies are specificfor the bark lectin. The antibodies against the lectin fromRobinia bark cross-reacted with polypeptides in extracts ofthe seeds and bark of Sophora japonica, indicating that thelectin from Robinia bark is immunologically related to the lectinsof Sophora. However, the antibodies did not cross-react withproteins from Robinia seeds and leaves. The first twenty aminoacid residues from the N-terminus of the lectin from Robiniabark were determined and compared with those of the Sophoralectins. (Received July 13, 1991; Accepted December 12, 1991)  相似文献   

11.
Population genetic structure and patterns of gene flow are describedfor the euphausiid, Meganyctiphanes norvegica, in the NW AtlanticOcean based on DNA sequence variation of two regions of mitochondrialDNA (mtDNA). DNA sequences were determined for portions of cytochromeoxidase I (COI; 400 base pairs; 76 individuals) and cytochromeb (CYB; 300 base pairs; 101 individuals) for euphausiids collectedfrom the Gulf of Maine in 1991, the Gulf of St Lawrence in 1993and 1994, the Scotian Shelf in 1994, and Georges Bank in 1994.For comparison, M.norvegica collected from the fjords of westernNorway in 1992 were sequenced for COI (20 individuals) and CYB(18 individuals). COI was less variable than CYB, based on bothhaplotype (h=0.6847 for COI; 0.9077 for CYB) and nucleotidediversities (  相似文献   

12.
The Atlantic and Mediterranean flabellinid Flabellina affinis(Gmelin, 1791) (Opisthobranchia, Nudi-branchia, Aeolidoidea)is examined morphologically, anatomically and histologicallywith special emphasis on characters which have been widely neglectedin recent literature (e.g. the histological structure of theoral glands, typhlosole). The study provides detailed data aboutall organ systems which are compared to existing data of otherauthors. The species described as Flabellina affinis by Bergh(1875; 1886) is considered not to be conspecific with the Flabellinaaffinis examined in this and other studies. Furthermore, Flabellinaaffinis is compared to other Mediterranean species, especiallyF. ischitana (Hirano & Thompson, 1990). F. ischitana differsfrom F. affinis mainly by the structure of the genital system.The phylogenetic trees presented for the genus by Gosliner &Kuzirian (1990) and Gosliner & Willan (1991) are discussed. (Received 5 August 1996; accepted 9 June 1997)  相似文献   

13.
A norepinephrine solution in which intact plants of Lemna paucicostatahad been immersed for 30 min or on which intact Lemna plantshad been placed for 24 h had strong flower-inducing activityin L. paucicostata 151, but norepinephrine added to the distilledwater in which Lemna plants had been immersed had no activity. (Received May 24, 1991; Accepted July 5, 1991)  相似文献   

14.
The incidence of the shell-boring parasite Polydora ciliatain Mytilus edulis from the Conwy estuary, North Wales is described.Amongst mussels >40 mm in shell length both the occurrenceand abundance of P. ciliata increased steeply with host size.Infestation was highest amongst mussels near the mouth of theestuary where around 60–65% of the population was parasitized;no systematic relationship between the incidence of P. ciliataand tidal elevation was observed. Mussel condition was negativelycorrelated with the degree of infestation. Moderately and heavilyinfested mussels, however, never accounted for more than ca.10% of this population and the overall detrimental effects ofP. ciliata on growth and production is thus probably quite small.Whilst heavily infested mussels were evidently more vulnerableto predation, the shore crab, Carcinus maenas, selected smaller,non-infested mussels whenever these were available. No obviousrelationships were found between the presence of P. ciliataand the incidence of either pearls or pea crabs. (Received 14 January 1991; accepted 2 April 1991)  相似文献   

15.
In situ hybridization was used to localize the sites of expressionfor two a-amylase genes (RAmy1A and RAmy3D) in rice (Oryza sativaL.) over five days of germination. Messenger RNAs from bothgenes were initially detected in the scutellar epithelium andappeared at later stages of germination in the aleurone layer.RAmy3D mRNA reached its peak of accumulation 2 days(d) earlierin the scutellar epithelium than RAmy1A mRNA. Both mRNAs continuedto accumulate in the aleurone layer up to 5 d of germination,although RAmy1A mRNA reached significantly higher levels thanRAmy3D mRNA. Overall, the aleurone layer was responsible forproducing the majority of the total grain a-amylase mRNA. (Received July 27, 1991; Accepted November 6, 1991)  相似文献   

16.
With this paper we initiate a taxonomic review of the genusNapaeus from the Canary Islands, indicating the statisticalmethodology used therein. We discuss the taxonomic problem ofNapaeus (Napaeinus) nanodes (Shuttleworth, 1852), designateits lectotype and describe five new species: Napaeus (Napaeinus)doliolum Henríquez, Napaeus (Napaeinus) bechi Alonso& Ibáñez, Napaeus (Napaeus) taguluchensisHenríquez, Napaeus (Napaeus) pygmaeus Ibáñez& Alonso and Napaeus (Napaeus) tagamichensis Henríquez,the first two from Tenerife; and the other three from La Gomera.Furthermore, we discuss the general relationships of the genusand its two sub-genera, whose original diagnoses are deficient;because of this, we think that in the future a broad reviewof the subfamily Eninae will be necessary in order to clarifythe actual position of this subfamily in the Canary Islands. (Received 11 March 1991; accepted 22 September 1992)  相似文献   

17.
A pathogenic fungus of pea, Mycosphaerella pinodes, secretesa so-called "suppressor" in its pycnospore germination fluid.The suppressor blocks the defense responses and induces localsusceptibility (accessibility) in pea plants to agents thatare not pathogenic in pea. The suppressor nonspecifically inhibitsthe ATPase activity in plasma membranes prepared from pea, soybean,kidney bean, cowpea and barley plants. However, cytochemicalstudies by electron microscopy indicate that the suppressorspecifically inhibits the ATPase in pea cell membranes, butnot in those of four other plant species tested. That is, thespecificity of the suppressor appears at the cell and/or tissuelevel, but is not evident in vitro. Furthermore, the inhibitoryeffect of the suppressor is temporary because the ATPase activityrecovers 9 h after the treatment. A similar effect was observedafter inoculation with M. pinodes but not with a nonpathogenof pea, M. ligulicola. The role of the suppressor in host-parasitespecificity is discussed. (Received April 9, 1991; Accepted August 6, 1991)  相似文献   

18.
Variation at the leucine aminopeptidase (Lap), glucose phosphateisomerase (Gpi) and tetrazolium oxidase (To) loci was investigatedin samples of three populations, Al-Mayana (MAY), Shigita (SH)and Mina Salman (MS), of Pinctada radiata from pearl oysterbeds around Bahrain. The To locus was monomor-phic. SignificantLap and Gpi heterozygote deficiencies were evident and it issuggested that these were generated by selection. The MS population,to the East of Bahrain, differed significantly in Gpi allelefrequencies from both Northern populations (MAY, SH) and Nei'sgenetic identity indicates a close relationship between theNorthern populations. Measurements of shell morphometrics were used both as ratiosof one dimension to another, and as regressions of one dimensionon another to examine relatedness between populations. Boththese mor-phometric approaches gave different results from eachother and also differed from the electrophoretic data. It isconcluded that estimates of relatedness in pearl oysters basedon electrophoretic data will be more reliable than those basedon shell shape. (Received 20 November 1990; accepted 12 April 1991)  相似文献   

19.
When Azolla plants (Azolla filiculoides vax.japonica) were grownin media with high concentrations of ammonium ions at pH 3.5,numbers of cyanobionts in apical portions were very much reduced.Microscopic observations revealed that cyanobionts in theseplants were preferentially damaged, with resultant death andlysis. (Received August 2, 1991; Accepted December 27, 1991)  相似文献   

20.
We have isolated cDNAs that correspond to three distinct low-temperature-inducedmRNAs from rice cells using an effective, simple subtractionmethod. The corresponding genes were designated lip (gene encodinglow-temperature-induced protein) –5,–9 and –19.The expression of these genes was slightly stimulated lip5 andlip19) or unaffected (lip9) by abscisic acid, unlike the expressionof the rabl6A-D genes which are readily induced by either abscisicacid or high osmotic stress. Time-course analysis revealed thatwhile the lip5 gene was induced 3 h after temperature down-shift,and the lip9 and lipl9 genes were induced 6 h after such a shift. 1Present address: Division of Molecular Medicine, Clinical ResearchCentre, Northwick Park Hospital, Harrow, Middlesex HA1 3UJ,U.K. (Received June 29, 1991; Accepted October 7, 1991)  相似文献   

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