Organization of a cloned repetitive DNA fragment in mosquito genomes (Diptera: Culicidae)

The structure and genomic organization of a cloned 5.2-kb repetitive DNA fragment, H-85, isolated from the Aedes albopictus genome have been examined. In situ hybridization of the 3H-labeled H-85 DNA to the meiotic and mitotic chromosome preparations of Ae. albopictus shows that the sequences homologous to H-85 DNA are dispersed throughout the length of all three pairs of chromosomes. A similar pattern of in situ hybridization appears in Aedes seatoi, Aedes flavopictus, and Aedes aegypti. The study shows that the arrangement of sequences in the cloned 5.2-kb fragment is rare in the Ae. albopictus genome. Dot-blot hybridization reveals that the sequences homologous to H-85 DNA are present in 12 species of mosquitoes examined, belonging to six genera in subfamilies Culicinae ad Anophelinae. The H-85 sequences are also present in the genome of Mochlonyx velutinus of the nematocerous family Chaoboridae, earlier proposed as the ancestor of the mosquito family Culicidae. Although the sequences homologous to H-85 DNA are present in different species of mosquitoes, they have diverged in their structure and organization. The cloned 5.2-kb fragment is composed of elements of different and independently evolving repetitive DNA families.Key words: repetitive DNA, organization, mosquitoes.

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Detection of hepatopancreatic parvovirus in Thai shrimp Penaeus monodon by in situ hybridization, dot blot hybridization and PCR amplification

Diseases of Aquatic Organisms ◽

10.3354/dao051227 ◽

2002 ◽

Vol 51 ◽

pp. 227-232 ◽

Cited By ~ 31

Author(s):

J Phromjai ◽

V Boonsaeng ◽

B Withyachumnarnkul ◽

TW Flegel

Keyword(s):

In Situ Hybridization ◽

Blot Hybridization ◽

Penaeus Monodon ◽

Pcr Amplification ◽

Dot Blot ◽

Dot Blot Hybridization ◽

Hepatopancreatic Parvovirus

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Biotinylated probes to detect Leptospira interrogans on dot blot hybridization or by in situ hybridization

Letters in Applied Microbiology ◽

10.1111/j.1472-765x.1991.tb00532.x ◽

1991 ◽

Vol 12 (5) ◽

pp. 171-176 ◽

Cited By ~ 1

Author(s):

P. Fach ◽

Daniele Trap ◽

J.P. Guillou

Keyword(s):

In Situ Hybridization ◽

Blot Hybridization ◽

Leptospira Interrogans ◽

Dot Blot ◽

Dot Blot Hybridization ◽

Biotinylated Probes

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Human Papillomavirus DNA in Anal CarcinomasComparison of In Situ and Dot Blot Hybridization

American Journal of Clinical Pathology ◽

10.1093/ajcp/96.3.318 ◽

1991 ◽

Vol 96 (3) ◽

pp. 318-325 ◽

Cited By ~ 11

Author(s):

MÁire A. Duggan ◽

Valerie F. Boras ◽

Masafumi Inoue ◽

S. Elizabeth McGregor

Keyword(s):

Human Papillomavirus ◽

Blot Hybridization ◽

Dot Blot ◽

Dot Blot Hybridization ◽

Papillomavirus Dna

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Molecular Epidemiology of Oral Treponemes Associated with Periodontal Disease

Journal of Clinical Microbiology ◽

10.1128/jcm.36.5.1399-1403.1998 ◽

1998 ◽

Vol 36 (5) ◽

pp. 1399-1403 ◽

Cited By ~ 79

Author(s):

Annette Moter ◽

Carina Hoenig ◽

Bong-Kyu Choi ◽

Birgit Riep ◽

Ulf B. Göbel

Keyword(s):

In Situ Hybridization ◽

Alveolar Bone ◽

Blot Hybridization ◽

Dark Field ◽

Causative Role ◽

Oligonucleotide Probes ◽

Dot Blot ◽

Dark Field Microscopy ◽

Healthy Control

Periodontitis, a disease responsible for tooth loss worldwide, is characterized by chronic inflammation of the periodontium, eventually leading to destruction of periodontal ligaments and supporting alveolar bone. Spirochetes, identified by dark-field microscopy as being the most predominant bacteria in advanced lesions, are thought to play a causative role. Various spirochetal morphotypes were observed, but most of these morphotypes are as yet uncultivable. To assess the role of these organisms we designed oligonucleotide probes for the identification of both cultivable and so far uncultivable spirochetes in periodontitis patients. Subgingival plaque specimens taken from diseased sites (n = 200) and healthy control sites (n = 44) from 53 patients with rapidly progressive periodontitis (RPP) were submitted to direct in situ hybridization or dot blot hybridization after prior amplification with eubacterial primers. Spirochetes were found in all patients, but their distributions varied considerably. Parallel use of oligonucleotide probes specific for cultivable or so far uncultivable treponemes suggested the presence of novel yet unknown organisms at a high frequency. These uncultivable treponemes were visualized by fluorescence in situ hybridization, and their morphologies, sizes, and numbers could be estimated. All RPP patients included in this study harbored oral treponemes that represent either novel species, e.g.,Treponema maltophilum, or uncultivable phylotypes. Therefore, it is necessary to include these organisms in etiologic considerations and to strengthen efforts to cultivate these as yet uncultivable treponemes.

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Tandem repeat DNA localizing on the proximal DAPI bands of chromosomes in Larix, Pinaceae

Genome ◽

10.1139/g02-041 ◽

2002 ◽

Vol 45 (4) ◽

pp. 777-783 ◽

Cited By ~ 9

Author(s):

Masahiro Hizume ◽

Fukashi Shibata ◽

Ayako Matsumoto ◽

Yukie Maruyama ◽

Eiji Hayashi ◽

...

Keyword(s):

In Situ Hybridization ◽

Fluorescence In Situ Hybridization ◽

Repetitive Dna ◽

Genomic Dna ◽

Repeat Unit ◽

Blot Hybridization ◽

Southern Blot Hybridization ◽

Repeat Sequence ◽

Proximal Region

Repetitive DNA was cloned from HindIII-digested genomic DNA of Larix leptolepis. The repetitive DNA was about 170 bp long, had an AT content of 67%, and was organized tandemly in the genome. Using fluorescence in situ hybridization and subsequent DAPI banding, the repetitive DNA was localized in DAPI bands at the proximal region of one arm of chromosomes in L. leptolepis and Larix chinensis. Southern blot hybridization to genomic DNA of seven species and five varieties probed with cloned repetitive DNA showed that the repetitive DNA family was present in a tandem organization in genomes of all Larix taxa examined. In addition to the 170-bp sequence, a 220-bp sequence belonging to the same DNA family was also present in 10 taxa. The 220-bp repeat unit was a partial duplication of the 170-bp repeat unit. The 220-bp repeat unit was more abundant in L. chinensis and Larix potaninii var. macrocarpa than in other taxa. The repetitive DNA composed 2.03.4% of the genome in most taxa and 0.3 and 0.5% of the genome in L. chinensis and L. potaninii var. macrocarpa, respectively. The unique distribution of the 220-bp repeat unit in Larix indicates the close relationship of these two species. In the family Pinaceae, the LPD (Larix proximal DAPI band specific repeat sequence family) family sequence is widely distributed, but their amount is very small except in the genus Larix. The abundant LPD family in Larix will occur after its speciation.Key words: AT-rich tandem repetitive DNA, fluorescence in situ hybridization, Larix, proximal DAPI band.

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Species-specific DNA probes for the identification of African trypanosomes in tsetse flies

Parasitology ◽

10.1017/s0031182000066749 ◽

1988 ◽

Vol 97 (1) ◽

pp. 63-73 ◽

Cited By ~ 84

Author(s):

W. C. Gibson ◽

P. Dukes ◽

J. K. Gashumba

Keyword(s):

Repeat Unit ◽

Blot Hybridization ◽

Dna Probes ◽

Tsetse Flies ◽

Dot Blot ◽

Specific Group ◽

African Trypanosomes ◽

Dot Blot Hybridization ◽

Species Specific

SUMMARYWe have obtained 5 specific DNA probes for African trypanosomes of the subgenera Trypanozoon and Nannomonas. Each probe consists of one repeat unit of the major repetitive DNA (satellite DNA) of each species or intra-specific group. One probe hybridized with all members of subgenus Trypanozoon (except T. equiperdum which was not tested). In subgenus Nannomonas, one probe recognized T. simiae, but 3 probes were needed to identify all stocks of T. congolense available. Each of the 3 latter probes recognized trypanosomes from one of the 3 major groups of T. congolense previously defined by isoenzyme characterization, i.e. savannah, forest and Kenya coast types. As few as 100 trypanosomes could be unequivocally identified by dot blot hybridization and individual trypanosomes could be identified by in situ hybridization. We show how this simple methodology can be used in the field for the identification of immature and mature trypanosome infections in tsetse.

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Variations of Bacterial Populations in Human Feces Measured by Fluorescent In Situ Hybridization with Group-Specific 16S rRNA-Targeted Oligonucleotide Probes

Applied and Environmental Microbiology ◽

10.1128/aem.64.9.3336-3345.1998 ◽

1998 ◽

Vol 64 (9) ◽

pp. 3336-3345 ◽

Cited By ~ 736

Author(s):

Alison H. Franks ◽

Hermie J. M. Harmsen ◽

Gerwin C. Raangs ◽

Gijsbert J. Jansen ◽

Frits Schut ◽

...

Keyword(s):

In Situ Hybridization ◽

16S Rrna ◽

Fluorescent In Situ Hybridization ◽

Blot Hybridization ◽

Dry Weight ◽

Oligonucleotide Probes ◽

Fecal Flora ◽

Dot Blot ◽

Clostridium Histolyticum

ABSTRACT Six 16S rRNA-targeted oligonucleotide probes were designed, validated, and used to quantify predominant groups of anaerobic bacteria in human fecal samples. A set of two probes was specific for species of the Bacteroides fragilis group and the speciesBacteroides distasonis. Two others were designed to detect species of the Clostridium histolyticum and theClostridium lituseburense groups. Another probe was designed for the genera Streptococcus andLactococcus, and the final probe was designed for the species of the Clostridium coccoides-Eubacterium rectalegroup. The temperature of dissociation of each of the probes was determined. The specificities of the probes for a collection of target and reference organisms were tested by dot blot hybridization and fluorescent in situ hybridization (FISH). The new probes were used in initial FISH experiments to enumerate human fecal bacteria. The combination of the two Bacteroides-specific probes detected a mean of 5.4 × 1010 cells per g (dry weight) of feces; the Clostridium coccoides-Eubacterium rectalegroup-specific probe detected a mean of 7.2 × 1010cells per g (dry weight) of feces. The Clostridium histolyticum, Clostridium lituseburense, andStreptococcus-Lactococcus group-specific probes detected only numbers of cells ranging from 1 × 107 to 7 × 108 per g (dry weight) of feces. Three of the newly designed probes and three additional probes were used in further FISH experiments to study the fecal flora composition of nine volunteers over a period of 8 months. The combination of probes was able to detect at least two-thirds of the fecal flora. The normal biological variations within the fecal populations of the volunteers were determined and indicated that these variations should be considered when evaluating the effects of agents modulating the flora.

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Cytogenetic manifestations associated with the reversion, by gene amplification, at the HGPRT locus in V79 Chinese hamster cells

Genetics Research ◽

10.1017/s0016672300028172 ◽

1989 ◽

Vol 53 (3) ◽

pp. 201-206

Author(s):

A. Di Leonardo ◽

C. Agnese ◽

P. Cavolina ◽

A. Maddalena ◽

G. Sciandrello ◽

...

Keyword(s):

Gene Amplification ◽

Cytogenetic Analysis ◽

Blot Hybridization ◽

Chinese Hamster ◽

Mutant Line ◽

Dot Blot ◽

Chinese Hamster Cells ◽

Dot Blot Hybridization ◽

Clonal Origin

SummarySome HGPRT spontaneous revertants were isolated from a mutant line (E2) of V79 Chinese hamster cells and phenotypically characterized. Dot–Blot hybridization with a 32P-Iabelled HGPRT probe revealed an increase in the number of HGPRT sequences in some of these revertants, suggesting the occurrence of gene amplification. Cytogenetic analysis performed in three of these revertants showed a characteristic abnormally banding region (ABR) on the elongated p arm of the X chromosome. In Situ hybridization in one revertant (RHE2) showed that the amplified sequences reside on the p+ arm of the X chromsome in two different localizations. Because of the very probable clonal origin of the revertant, these features indicate that the amplified sequences might rearrange after their integration into the chromosome.

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Repetitive DNA sequences in Crocus vernus Hill (Iridaceae): The genomic organization and distribution of dispersed elements in the genus Crocus and its allies

Genome ◽

10.1139/g00-044 ◽

2000 ◽

Vol 43 (5) ◽

pp. 902-909 ◽

Cited By ~ 14

Author(s):

S Frello ◽

J S Heslop-Harrison

Keyword(s):

In Situ Hybridization ◽

Sequence Analysis ◽

Repetitive Dna ◽

Dna Sequences ◽

Southern Hybridization ◽

Genomic Organization ◽

Organizer Region ◽

Nucleolar Organizer Region ◽

Taxonomic Structure

Eight clones of repetitive DNA were isolated from Crocus vernus Hill. The genomic organization of the clones was analyzed by in situ hybridization to C. vernus and Southern hybridization to a range of Crocus and other species. Seven clones were used for in situ hybridization. Sequence analysis showed that all eight clones were nonhomologous, and thus represented eight different sequence-families. In situ hybridization showed that six were dispersed in high copy numbers on all chromosomes of the C. vernus genome, whereas one was localized proximal to the secondary constriction, at the NOR (nucleolar organizer region) and was not further analyzed, as it was considered part of the 18S-25S rDNA repeat. Except for short palindromes, none of the sequences showed notable internal structures. Clone pCvKB4 showed homology to the reverse transcriptase gene of Ty1-copia-like retrotransposons; the others showed no homology to known sequences. When used as probes for Southern hybridization, four showed a ladder of 3-4 bands superimposed by irregular patterns, indicating organization in short tandem arrays. Each clone had a unique distribution among Crocus species (12-16 species analyzed with each clone) and six species of Iridaceae, Liliaceae, and Amaryllidaceae; all seven investigated sequences were Iridaceae specific and four were Crocus specific. The species distribution of these seven clones showed notable discrepancies with the taxonomic subdivision of the genus at the subgenus, section, and series levels. The results suggest that the phylogeny and taxonomic structure of the genus Crocus might need reconsideration. The analysis of repetitive DNA as a major and rapidly evolving part of the genome could contribute to the study of species relationships and evolution.Key words: phylogeny, evolution, in situ hybridization, sequence analysis, dispersed elements.

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