Tandem arrangement of tubulin genes in the protozoan parasite Leishmania enriettii.

The arrangement of developmentally regulated alpha- and beta-tubulin genes has been studied in the parasitic protozoan Leishmania enriettii by using Southern blot hybridization analysis. The alpha-tubulin genes occur in a tandem repeat whose monomeric unit may be represented by a 2-kilobase PstI fragment. Similarly, the beta-tubulin genes probably occur in a separate tandem repeat consisting of approximately 4-kilobase units unlinked to the alpha-tubulin repeats.

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Structure and arrangement of the beta-tubulin genes of Leishmania tropica

Molecular and Cellular Biology ◽

10.1128/mcb.4.7.1372-1383.1984 ◽

1984 ◽

Vol 4 (7) ◽

pp. 1372-1383

Author(s):

P L Huang ◽

B E Roberts ◽

D M Pratt ◽

J R David ◽

J S Miller

Keyword(s):

Protozoan Parasite ◽

Leishmania Tropica ◽

Beta Tubulin ◽

S1 Nuclease ◽

Alpha Tubulin ◽

Tubulin Genes ◽

Repeat Units ◽

Genes Encoding ◽

Tubulin Mrna ◽

Parasite Leishmania

We studied the organization and arrangement of the genes encoding beta-tubulin in the protozoan parasite Leishmania tropica and examined the structure and orientation of the beta-tubulin mRNA relative to the gene. There were found to be eight to nine beta-tubulin genes arranged in an array of direct tandem repeat units with a length of 3.8 kilobase pairs, and they were extremely homologous, if not identical, in sequence. These repeat units did not contain the alpha-tubulin genes. The transcribed sequences within the beta-tubulin genes were localized, and the orientation of the major alpha-tubulin mRNA was mapped on the gene by S1 nuclease analysis.

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Structure and arrangement of the beta-tubulin genes of Leishmania tropica.

Molecular and Cellular Biology ◽

10.1128/mcb.4.7.1372 ◽

1984 ◽

Vol 4 (7) ◽

pp. 1372-1383 ◽

Cited By ~ 31

Author(s):

P L Huang ◽

B E Roberts ◽

D M Pratt ◽

J R David ◽

J S Miller

Keyword(s):

Protozoan Parasite ◽

Leishmania Tropica ◽

Beta Tubulin ◽

S1 Nuclease ◽

Alpha Tubulin ◽

Tubulin Genes ◽

Repeat Units ◽

Genes Encoding ◽

Tubulin Mrna ◽

Parasite Leishmania

We studied the organization and arrangement of the genes encoding beta-tubulin in the protozoan parasite Leishmania tropica and examined the structure and orientation of the beta-tubulin mRNA relative to the gene. There were found to be eight to nine beta-tubulin genes arranged in an array of direct tandem repeat units with a length of 3.8 kilobase pairs, and they were extremely homologous, if not identical, in sequence. These repeat units did not contain the alpha-tubulin genes. The transcribed sequences within the beta-tubulin genes were localized, and the orientation of the major alpha-tubulin mRNA was mapped on the gene by S1 nuclease analysis.

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Expression of alpha- and beta-tubulin genes during dimorphic-phase transitions of Histoplasma capsulatum

Molecular and Cellular Biology ◽

10.1128/mcb.9.5.2042-2049.1989 ◽

1989 ◽

Vol 9 (5) ◽

pp. 2042-2049

Author(s):

G S Harris ◽

E J Keath ◽

J Medoff

Keyword(s):

Phase Transitions ◽

Histoplasma Capsulatum ◽

Blot Hybridization ◽

Dot Blot ◽

Dimorphic Fungus ◽

Tubulin Gene ◽

Beta Tubulin ◽

Two Dimensional Gel Electrophoresis ◽

Western Blots ◽

Alpha Tubulin

Recent investigations have confirmed the presence of one alpha-tubulin gene (TUB1) and one beta-tubulin gene (TUB2) in the dimorphic fungus Histoplasma capsulatum. In the present study, Northern blot (RNA blot) analyses revealed multiple alpha-tubulin transcripts and a single beta-tubulin transcript in the yeast and mycelial phases of the high-virulence 217B strain and low-virulence Downs strain. S1 nuclease protection assays demonstrated one initiation start site and two major stop sites for the TUB1 transcripts, suggesting that variations in 3' processing generate the alpha-tubulin messages of 2.5 and 2.0 kilobases. Dot blot hybridization experiments indicated that tubulin gene expression is developmentally regulated during the dimorphic phase transitions. alpha- and beta-tubulin mRNAs increased six- to eightfold during the yeast-to-mycelium conversion and decreased two- to threefold during the reverse transition. These changes in tubulin mRNA content coincided with major morphological events associated with H. capsulatum development. Western blots (immunoblots) of H. capsulatum yeast-specific proteins resolved by two-dimensional gel electrophoresis demonstrated a single alpha- and a single beta-tubulin isoform. Multiple tubulin polypeptides expressed in mycelia are probably products of posttranslational modifications.

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Phenotypic consequences of tubulin overproduction in Saccharomyces cerevisiae: differences between alpha-tubulin and beta-tubulin

Molecular and Cellular Biology ◽

10.1128/mcb.10.10.5295-5304.1990 ◽

1990 ◽

Vol 10 (10) ◽

pp. 5295-5304

Author(s):

B Weinstein ◽

F Solomon

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Division ◽

Microtubule Assembly ◽

Beta Tubulin ◽

Alpha Tubulin ◽

Tubulin Genes ◽

Data Support ◽

Cell Biol

Overexpression of alpha- and beta-tubulin genes in Saccharomyces cerevisiae, separately or together, leads to accumulation of large excesses of each of the polypeptides and arrest of cell division. However, other consequences of overexpression of these genes differ in several ways. As shown previously (D. Burke, P. Gasdaska, and L. Hartwell, Mol. Cell. Biol. 9:1049-1059, 1989), overexpression of beta-tubulin leads, at early times, to loss of microtubule structures and loss of viability. Eventually, the excess beta-tubulin forms abnormal structures. We show here that, in contrast, overexpression of alpha-tubulin led to none of these phenotypes and in fact could suppress each of the phenotypes associated with beta-tubulin accumulation. Truncated forms of beta-tubulin that were not competent to carry out microtubule functions also failed to elicit the beta-tubulin-specific phenotypes when overexpressed. The data support the hypothesis that beta-tubulin in excess over alpha-tubulin is uniquely toxic, perhaps because it interferes with normal microtubule assembly.

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The two alpha-tubulin genes of Chlamydomonas reinhardi code for slightly different proteins.

Molecular and Cellular Biology ◽

10.1128/mcb.5.9.2389 ◽

1985 ◽

Vol 5 (9) ◽

pp. 2389-2398 ◽

Cited By ~ 112

Author(s):

C D Silflow ◽

R L Chisholm ◽

T W Conner ◽

L P Ranum

Keyword(s):

Amino Acid ◽

Amino Acid Sequences ◽

Cdna Clones ◽

Gene Products ◽

Beta Tubulin ◽

Alpha Tubulin ◽

Tubulin Genes ◽

Total Complement ◽

Cloned Gene ◽

Net Charges

Full-length cDNA clones corresponding to the transcripts of the two alpha-tubulin genes in Chlamydomonas reinhardi were isolated. DNA sequence analysis of the cDNA clones and cloned gene fragments showed that each gene contains 1,356 base pairs of coding sequence, predicting alpha-tubulin products of 451 amino acids. Of the 27 nucleotide differences between the two genes, only two result in predicted amino acid differences between the two gene products. In the more divergent alpha 2 gene, a leucine replaces an arginine at amino acid 308, and a valine replaces a glycine at amino acid 366. The results predicted that two alpha-tubulin proteins with different net charges are produced as primary gene products. The predicted amino acid sequences are 86 and 70% homologous with alpha-tubulins from rat brain and Schizosaccharomyces pombe, respectively. Each gene had two intervening sequences, located at identical positions. Portions of an intervening sequence highly conserved between the two beta-tubulin genes are also found in the second intervening sequence of each of the alpha genes. These results, together with our earlier report of the beta-tubulin sequences in C. reinhardi, present a picture of the total complement of genetic information for tubulin in this organism.

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Characterization of the pTFI91 -family replicon of Thiobacillus ferrooxidans plasmids

Canadian Journal of Microbiology ◽

10.1139/m95-048 ◽

1995 ◽

Vol 41 (4-5) ◽

pp. 354-365 ◽

Cited By ~ 6

Author(s):

Leena Chakravarty ◽

Thomas J. Zupancic ◽

Beth Baker ◽

Joseph D. Kittle ◽

Ilona J. Fry ◽

...

Keyword(s):

Dna Sequences ◽

Thiobacillus Ferrooxidans ◽

Blot Hybridization ◽

Marker Gene ◽

Southern Blot Hybridization ◽

Structural Features ◽

Broad Host Range ◽

Origin Of Replication ◽

E Coli ◽

Southern Blot Hybridization Analysis

Plasmids found in six strains of Thiobacillus ferrooxidans were mapped and compared in an effort to detect the origin of replication. Four strains yielded an identical 9.8-kb plasmid, pTFI91. Restriction mapping and Southern blot hybridization analysis were used to confirm this finding. Dissimilar plasmids found in two other strains contained a conserved 2.2-kb SacI region common to pTFI91. DNA sequence analysis of this region showed structural features common to bacterial plasmid replicons. A comparison of the pTFI91 origin with those of T. ferrooxidans pTF-FC2 and other broad host range vectors did not show significant homologous DNA sequences. To verify the replication function, a chloramphenicol acetyl transferase marker gene was ligated at the unique sites of pTFI91, and the plasmid was transformed into Escherichia coli DH5α cells but no transformants were identified. To test the replication of pTFI91 independent of DNA polymerase I in E. coli, different restriction fragments of pTFI91 were cloned into pHSG398 (Cmr, ColEI origin) and transformed into the polA1 mutant SF800, but chloramphenicol-resistant transformants were not detected. Electrotransformation of T. ferrooxidans TFI-70 and Pseudomonas putida ATCC 19151 also failed to yield transformants. The results suggested that the pTFI91 plasmid replicon does not function either in E. coli or in P. putida. Since pTFI91 contains the same origin of replication as other plasmids in several other T. ferrooxidans strains, this replicon may be commonly distributed in T. ferrooxidans.Key words: nucleotide sequence, origin of replication, plasmid DNA, replicon, Thiobacillus ferrooxidans.

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Leptospira interrogans serovar sejroe infection in a group of laboratory dogs

Laboratory Animals ◽

10.1258/002367795781088261 ◽

1995 ◽

Vol 29 (3) ◽

pp. 300-306 ◽

Cited By ~ 14

Author(s):

E. Scanziani ◽

L. Crippa ◽

Anna M. Giusti ◽

M. Luini ◽

Maria L. Pacciarini ◽

...

Keyword(s):

Interstitial Nephritis ◽

Urine Analysis ◽

Blot Hybridization ◽

Southern Blot Hybridization ◽

Leptospira Interrogans ◽

Normal Ranges ◽

Southern Blot Hybridization Analysis ◽

Antibody Titres ◽

Renal Infection ◽

Endonuclease Digestion

Interstitial nephritis was seen histologically in 19 (59%) out of 32 pure-breed beagle dogs (16 males and 16 females) subjected to standard safety tests. In these animals no clinical abnormalities were observed and all the tested parameters (haematology, biochemistry and urine analysis) were within the normal ranges. Leptospiral antibody titres ranging from 1:100 to 1:6400, against a serovar ( hardio) belonging to the Sejroe serogroup, were detected by the microscopic agglutination test (MAT) in the serum of the 19 dogs with interstitial nephritis. All animals without renal lesions were seronegative. Leptospiral antigen was detected immunohistochemically in the kidneys of 4 dogs; leptospires were detected in Warthin-Starry stained sections of one dog. Leptospires were isolated from the kidneys of 3 of the 4 dogs examined by bacterial culture. The isolated strains were typed as serovar sejroe by restriction endonuclease digestion and Southern blot hybridization analysis of their DNA. It was concluded that Leptospira interrogans serovar sejroe, was responsible for an asymptomatic chronic renal infection which was widespread in this group of laboratory dogs.

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Genetic Transformation of Garlic (Allium sativum L.) by Particle Bombardment

HortScience ◽

10.21273/hortsci.39.6.1208 ◽

2004 ◽

Vol 39 (6) ◽

pp. 1208-1211 ◽

Cited By ~ 5

Author(s):

Alejandrina Robledo-Paz ◽

José Luis Cabrera-Ponce ◽

Víctor Manuel Villalobos-Arámbula ◽

Luis Herrera-Estrella ◽

Alba Estela Jofre-Garfias

Keyword(s):

Transgenic Plants ◽

Plasmid Dna ◽

Allium Sativum ◽

Microprojectile Bombardment ◽

Blot Hybridization ◽

Southern Blot Hybridization ◽

Hygromycin B ◽

Gus Histochemical Assay ◽

Embryogenic Calluses ◽

Southern Blot Hybridization Analysis

Microprojectile bombardment was used to introduce DNA into embryogenic callus of garlic (Allium sativum L.) and produce stably transformed garlic plants. Embryogenic calluses, derived from garlic cultivar `GT96-1', were bombarded with plasmid DNA containing genes coding for hygromycin phosphotransferase and β-glucuronidase. Putatively transformed calluses were identified in the bombarded tissue after 4 months of selection on 20 mg·L-1 hygromycin B. The transgenic nature of the selected material was demonstrated by GUS histochemical assay and Southern blot hybridization analysis, and twenty transgenic plants were regenerated.

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