Linear amplicons as precursors of amplified circles in methotrexate-resistant Leishmania tarentolae
نویسندگان
چکیده
منابع مشابه
Co-existence of circular and multiple linear amplicons in methotrexate-resistant Leishmania.
Circular and linear amplicons were analyzed in detail in Leishmania tropica cells resistant to methotrexate (MTX). Both types of elements presented sequences related to the H locus and coexisted in resistant cells. The linear amplicons appeared first during the selection process (at 10 microM MTX) and varied with regard to size and structure in cells exposed to increasing concentrations of drug...
متن کاملUnstable DNA amplifications in methotrexate-resistant Leishmania consist of extrachromosomal circles which relocalize during stabilization.
Methotrexate-resistant Leishmania tropica contain two separate regions of DNA amplification, one encoding the bifunctional thymidylate synthetase-dihydrofolate reductase (TS-DHFR) characteristic of protozoans and the other of yet unknown function. The amplified DNAs are initially found as extrachromosomal closed circular forms, which are unstable in the absence of selection. After prolonged cul...
متن کاملRecombinant protein expression in Leishmania tarentolae.
A variety of recombinant protein expression systems have been developed for heterologous genes in both prokaryotic and eukaryotic systems such as bacteria, yeast, mammals, insects, transgenic animals, and plants. Recently Leishmania tarentolae, a trypanosomatid protozoan parasite of the white-spotted wall gecko (Tarentola annularis), has been suggested as candidate for heterologous genes expres...
متن کاملThe status of Leishmania tarentolae/Trypanosoma platydactyli.
Taxonomic studies and classification of Leishmania species have developed rapidly in recent years, but controversy still surrounds the relationships between those species infecting lizards and those infecting mammals. Some authorities maintain that the leishmanias o f lizards form a sufficiently distinct group to be ranked as a separate genus - Sauroleishmania(1,2) - while Wallbanks et al. have...
متن کاملMethotrexate-resistant Leishmania donovani genetically deficient in the folate-methotrexate transporter.
From a mutagenized population of wild type Leishmania donovani promastigotes, a clone was isolated in a single step by virtue of its resistance to 1 mM methotrexate, a potent inhibitor of dihydrofolate reductase. This methotrexate-selected cell line, MTXA5, was cross-resistant to aminopterin but just as sensitive to growth inhibition caused by pyrimethamine, trimethoprim, and cytotoxic purine a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nucleic Acids Research
سال: 1998
ISSN: 0305-1048,1362-4962
DOI: 10.1093/nar/26.14.3370