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101.
During research into microfungi that inhabit decaying parts of the monocotyledonous family Pandanaceae, three species of
Balaniopsis were collected. One is Balaniopsis africana as originally described and illustrated by Kiffer as Balanium africanum. The second species is conspecific with the specimen treated as Balaniopsis africana by Kirk, but is introduced here as a new species, Balaniopsis kirkii. The third, Balaniopsis dendroidea, is a new species from Australia.
Received: March 21, 2001 / Accepted: October 8, 2001 相似文献
102.
Marilen M. Parungao Sally C. Fryar Kevin D. Hyde 《Biodiversity and Conservation》2002,11(7):1185-1194
Ten leaves from each of 13 different tree types from two differentrainforest sites in North Queensland, Australia were examined in order toestablish the fungal diversity developing on these leaves. A total of 57microfungi were identified, most of which were mitosporic fungi. Speciesdiversity in terms of richness and evenness were compared and the Mt Lewis sitewas found to be richer as compared to the Butchers Creek site. Statisticalmeasurements of diversity indices, however, showed that the two forest siteswere of similar diversity. Thirty-six of the fungi identified occurred only onone leaf type, indicating possible host specificities or recurrences. The samplesize, however, is deemed to be insufficient, as a larger sample size may haveresulted in less of the fungi appearing to be host specific. It is recommendedthat future studies should include more leaf samples and less tree types. It isparticularly important that the same leaf species are collected within the samesite and at different sites in order to establish the effects of host on fungalcomposition. 相似文献
103.
Detection and taxonomic placement of endophytic fungi within frond tissues of Livistona chinensis based on rDNA sequences. 总被引:9,自引:0,他引:9
The 5.8S gene and flanking internal transcribed spacers (ITS1 and ITS2) of the rDNA were amplified from total DNA extracted from frond tissues of Livistona chinensis with universal and fungal-specific primers. These amplified fragments were cloned and sequenced. Phylogenetic analysis based on the 5.8S gene sequences indicated that the six clone sequences obtained were of different origins. Five sequences, P1-9, P2-6, P4-4, P4-5, and P4-7, belonged to the fungi and one sequence, P3-2, belonged to the plants. P1-9 was inferred to belong to the Basidiomycota based on the phylogenetic analysis of the 5.8S gene sequences but could not be identified to lower taxonomic levels. Further identification of the other four fungal clones to lower taxonomic levels was attempted based on phylogenetic analysis and sequence comparison of both the conserved 5.8S gene and the variable ITS regions. The origin of P2-6 was identified to be Glomerella and its anamorph Colletotrichum, the origins of P4-5 and P4-7 were Mycosphaerella and its anamorph Cladosporium, and the origin of P4-4 was the Herpotrichiellaceae. The direct approach to detection and taxonomic placement of endophytic fungi within host tissue without the need for conventional in vitro culturing is discussed. 相似文献
104.
Polytretophora macrospora is introduced based on specimens from two species ofPandanus in Seychelles. The new species is compared with currently accepted species. A key and a comparative synopsis toPolytetophora species are provided. Numerous specimens ofP. calcarata, collected on members of the Pandanaceae from Australia, Fiji, Hong Kong, Malaysia, New Caledonia, Palau, Philippines, Seychelles
and Solomon Islands are also reported, along withP. dendroidea onPandanus sp. from Malaysia. 相似文献
105.
106.
Certain species of urodeles and teleost fish can regenerate their tissues. Zebrafish have become a widely used model to study the spontaneous regeneration of adult tissues, such as the heart1, retina2, spinal cord3, optic nerve4, sensory hair cells5, and fins6.The zebrafish fin is a relatively simple appendage that is easily manipulated to study multiple stages in epimorphic regeneration. Classically, fin regeneration was characterized by three distinct stages: wound healing, blastema formation, and fin outgrowth. After amputating part of the fin, the surrounding epithelium proliferates and migrates over the wound. At 33 °C, this process occurs within six hours post-amputation (hpa, Figure 1B)6,7. Next, underlying cells from different lineages (ex. bone, blood, glia, fibroblast) re-enter the cell cycle to form a proliferative blastema, while the overlying epidermis continues to proliferate (Figure 1D)8. Outgrowth occurs as cells proximal to the blastema re-differentiate into their respective lineages to form new tissue (Figure 1E)8. Depending on the level of the amputation, full regeneration is completed in a week to a month.The expression of a large number of gene families, including wnt, hox, fgf, msx, retinoic acid, shh, notch, bmp, and activin-betaA genes, is up-regulated during specific stages of fin regeneration9-16. However, the roles of these genes and their encoded proteins during regeneration have been difficult to assess, unless a specific inhibitor for the protein exists13, a temperature-sensitive mutant exists or a transgenic animal (either overexpressing the wild-type protein or a dominant-negative protein) was generated7,12. We developed a reverse genetic technique to quickly and easily test the function of any gene during fin regeneration.Morpholino oligonucleotides are widely used to study loss of specific proteins during zebrafish, Xenopus, chick, and mouse development17-19. Morpholinos basepair with a complementary RNA sequence to either block pre-mRNA splicing or mRNA translation. We describe a method to efficiently introduce fluorescein-tagged antisense morpholinos into regenerating zebrafish fins to knockdown expression of the target protein. The morpholino is micro-injected into each blastema of the regenerating zebrafish tail fin and electroporated into the surrounding cells. Fluorescein provides the charge to electroporate the morpholino and to visualize the morpholino in the fin tissue.This protocol permits conditional protein knockdown to examine the role of specific proteins during regenerative fin outgrowth. In the Discussion, we describe how this approach can be adapted to study the role of specific proteins during wound healing or blastema formation, as well as a potential marker of cell migration during blastema formation. 相似文献
107.
D Tinker N Romero-Chapman K Reiser D Hyde R Rucker 《Archives of biochemistry and biophysics》1990,278(2):326-332
Accelerated proteolysis of tropoelastin and elastin occurs in the arteries of chicks rendered nutritionally copper-deficient. The process results in part from decreased elastin crosslinking. Repletion of copper-deficient chicks with copper causes a deposition of elastin that is proteinase resistant. Resistance to proteolysis is conferred within 48 h of dietary copper repletion. Deposition of aorta elastin to near normal values occurs after 3-4 days in copper-repleted chicks. Moreover, elastolysis was enhanced when the content of dehydrolysinonorleucine in elastin was abnormally low. The chemical modification of lysyl residue in elastin by citroconylation, however, did not influence the rate of elastolysis. We have shown previously that tropoelastin messenger RNA activity and synthesis are not influenced by dietary copper deprivation (1986, Biochem. J. 236, 17-23). Rather, as demonstrated herein, the decrease in elastin content in arteries of copper-deficient birds appears to be more the result of enhanced degradation. Restoration of normal crosslinking restores deposition and imparts resistance to elastolysis. Moreover, serum appears to be a good source of elastolytic proteinases when the elastin substrate is partially or abnormally crosslinked. 相似文献
108.
109.
Hubert Josien Thomas Bara Murali Rajagopalan John W. Clader William J. Greenlee Leonard Favreau Lynn A. Hyde Amin A. Nomeir Eric M. Parker Lixin Song Lili Zhang Qi Zhang 《Bioorganic & medicinal chemistry letters》2009,19(21):6032-6037
A new class of 2,6-disubstituted morpholine N-arylsulfonamide γ-secretase inhibitors was designed based on the introduction of a morpholine core in lieu or piperidine in our lead series. This resulted in compounds with improved CYP 3A4 profiles. Several analogs that were active at lowering Aβ levels in Tg CRND8 mice upon oral administration were identified. 相似文献
110.
The organization of nucleoprotein within fowlpox virus 总被引:1,自引:0,他引:1