title: Leishmania donovani: characterization and expression of ORFF, a gene amplified from the LDI locus.
abstract: The LD1 locus is a 27.5-kb region of chromosome 35 that is conserved among all species of Leishmania and is amplified in several different isolates. Here, we report the genomic distribution of ORFF, a gene from the LD1 region, and its expression at the RNA and protein levels in two Indian isolates of Leishmania donovani. In both of these isolates, ORFF was present as a single copy on chromosome 35. Densitometric analysis of ORFF mRNA abundance revealed relative abundance of 0.2 and 1.0 in AG83 and S-Lal, respectively. Antiserum against recombinant ORFF protein detected a protein of the predicted size ( approximately 34 kDa) in both strains. The protein is most abundant in mid-log-phase promastigotes and has a nuclear localization. The ORFF protein is preferentially expressed in L. donovani amastigotes but, in contrast, is expressed at higher levels in L. major promastigotes.
authors.affiliation: School of Life Science, Jawaharlal Nehru University, New Delhi, 110067, India.
authors.forename: A
authors.initials: A
authors.lastname: Ghosh
authors.forename: R
authors.initials: R
authors.lastname: Madhubala
authors.forename: P J
authors.initials: PJ
authors.lastname: Myler
authors.forename: K D
authors.initials: KD
authors.lastname: Stuart
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D015153:Blotting, Western; D002467:Cell Nucleus / Q000737:chemistry; D003720:Densitometry; D005784:Gene Amplification; D005786:Gene Expression Regulation; D007893:Leishmania donovani / Q000235:genetics* / Q000378:metabolism; D008163:Luminescent Measurements; D015800:Protozoan Proteins / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D016053:RNA, Protozoan / Q000032:analysis
chemical_list: C402106:ORFF protein, Leishmania; D015800:Protozoan Proteins; D012333:RNA, Messenger; D016053:RNA, Protozoan