%0 Journal Article %A Davoudi, Noushin %A Mahboudi, Fereidoun %A Azizi, Mohammad %A Adeli, Ahmad %A McMaster, Robert. W %T Introduction of Three Independent Selection Markers in Leishmania %J Iranian Biomedical Journal %V 7 %N 1 %U http://ibj.pasteur.ac.ir/article-1-547-en.html %R %D 2003 %K HSV-thymidine kinase (HSV-TK), Cytosine deaminase (CD), ganciclovir (GCV), 5-fluorocytosine (5-FC), nourseothericin (Ns), %X The pLE2SCX vector was developed for the stable expression of exogenous genes in the protozoan parasite Leishmania. The pLE2SCX construct contains three independent selection markers: herpes simplex virus thymidine kinase (HSV-TK), cytosine deaminase (CD) and streptothericin acetyltransferase gene (sat) in multiple cloning site, flanking by 5’ and 3’ untranslated regions of the previously cloned Leishmania major hexa-binding protein gene. Selection was based on resistance to the nourseothericin (Ns) which corresponds to sat gene. The two negative selection HSV-TK and CD genes, make the transformed cell sensitive to ganciclovir (GCV) and 5-fluorocytosine (5-FC). The vector was introduced into Leishmania promastigotes by electroporation and maintained as circular form. The selected transfectants were not grown on media with GCV or 5-FC. Using two drug sensitive selectable markers together on a vector is a novel strategy in gene cloning in Leishmania. This stable transfection vector has allowed the permanently expression of several different exogenous genes at the same time in Leishmania %> http://ibj.pasteur.ac.ir/article-1-547-en.pdf %P 13-18 %& 13 %! %9 Full Length/Original Article %L A-10-1-281 %+ %G eng %@ 1028-852X %[ 2003