+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Physical and genetic mapping of cloned ribosomal DNA from Toxoplasma gondii: primary and secondary structure of the 5S gene



Physical and genetic mapping of cloned ribosomal DNA from Toxoplasma gondii: primary and secondary structure of the 5S gene



Gene 114(2): 165-171



The ribosomal DNA (rDNA encoding rRNA) of the obligately intracellular protozoan parasite, Toxoplasma gondii, was identified, cloned, physically mapped, its copy number determined, and the 5S gene sequenced. Using total RNA as a probe, a collection of recombinant .lambda. phages containing copies of rDNA were isolated from a .lambda.2001 tachyzoite genomic library. Northern gel hybridization confirmed specific homology of the 7.5-kb rDNA unit, subcloned into pTZ18R, to T. gondii rRNA. The mapped rDNA found in pTOX1 contained small ribosomal subunit (SS; 18S)- and large ribosomal subunit (LS; 26S)-encoding genes localized using intragenic heterologous probes from the conserved sequences of the SS(18S) and LS(28S) Xenopus laevis genes. The physical mapping data, together with partial digestion experiments and Southern gel hybridization, confirmed a 7.5-kb rDNA unit arranged in a simple head-to-tail fashion that is tandemly repeated. We estimated the rDNA repeat copy number in T. gondii to be 110 copies per haploid tachyzoite genome. Parts of the SS gene and the complete 5S gene were sequenced. The 5S gene was found to be within the rDNA locus, a rare occurrence found only in some fungi and protozoa. Secondary-structure analysis revealed an organization remarkably similar to the 5S RNA of eukaryotes.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 007655369

Download citation: RISBibTeXText

PMID: 1601300

DOI: 10.1016/0378-1119(92)90570-f


Related references

Toxoplasma gondii and hammondia hammondi dna comparison using cloned ribosomal rna gene probes. Experimental Parasitology 63(3): 272-278, 1987

Secondary structure of Toxoplasma gondii ribosomal RNA elements. Abstracts of the General Meeting of the American Society for Microbiology 93: 207, 1993

Cloning primary structure and analysis of the large subunit ribosomal dna lsu from the parasite toxoplasma gondii. Abstracts of the General Meeting of the American Society for Microbiology 92: 198, 1992

The effect of toxoplasma antibodies after re infection with toxoplasma gondii part 2 communication investigations of the incidence of toxoplasma in peripheral blood after primary and secondary infection. Zentralblatt fuer Bakteriologie Parasitenkunde Infektionskrankheiten und Hygiene Erste Abteilung Originale Reihe A Medizinische Mikrobiologie und Parasitologie 238(1): 122-127, 1977

Primary structure of the dihydrofolate reductase-thymidylate synthase gene from Toxoplasma gondii. Journal of Biological Chemistry 268(9): 6269-6280, 1993

Primary structure of mature SAG1 gene of an Indonesian Toxoplasma gondii and comparison with other strains. Journal of Veterinary Science 7(3): 263-270, 2006

The effect of Toxoplasma antibodies after reinfection with T. gondii. II. Communication: investigations on the incidence of Toxoplasma in the peripheral blood after primary and secondary infection. Zentralblatt fur Bakteriologie, Parasitenkunde, Infektionskrankheiten und Hygiene, Abteilung 1, Originale, A 238(1): 122-127, 1977

The effect of toxoplasma antibodies after reinfection with T. gondii. II. Communication: investigations over the incidence of toxoplasma in peripheral blood after primary and secondary infection. Zentralblatt für Bakteriologie Parasitenkunde Infektionskrankheiten und Hygiene. Erste Abteilung Originale. Reihe A: Medizinische Mikrobiologie und Parasitologie 238(1): 122-127, 1977

Secondary structures and features of the 18S, 5.8S and 26S ribosomal RNAs from the apicomplexan parasite Toxoplasma gondii. Gene (Amsterdam) 173(2): 129-135, 1996

Isolation cloning and primary structure of the hypoxanthine guanine phosphoribosyltransferase hgprt gene from the parasite toxoplasma gondii. Program & Abstracts of the Interscience Conference on Antimicrobial Agents & Chemotherapy 32: 129, 1992

Toxoplasma gondii and Hammondia hammondi: DNA comparison using cloned rRNA gene probes. Experimental Parasitology 633: 272-278, 1987

Toxoplasma gondii: structure and characterization of the 26S ribosomal RNA and peptidyl transferase domain. Experimental Parasitology 83(3): 346-351, 1996

Determination of the primary structure and transcriptional activity of cloned oocyte 5s ribosomal rna gene variants revealed their intragenomic polymorphism. Molekulyarnaya Biologiya 23(5): 1295-1308, 1989