title: Leishmania replication protein A-1 binds in vivo single-stranded telomeric DNA.
abstract: Replication protein A (RPA) is a highly conserved heterotrimeric single-stranded DNA-binding protein involved in different events of DNA metabolism. In yeast, subunits 1 (RPA-1) and 2 (RPA-2) work also as telomerase recruiters and, in humans, the complex unfolds G-quartet structures formed by the 3' G-rich telomeric strand. In most eukaryotes, RPA-1 and RPA-2 bind DNA using multiple OB fold domains. In trypanosomatids, including Leishmania, RPA-1 has a canonical OB fold and a truncated RFA-1 structural domain. In Leishmania amazonensis, RPA-1 alone can form a complex in vitro with the telomeric G-rich strand. In this work, we show that LaRPA-1 is a nuclear protein that associates in vivo with Leishmania telomeres. We mapped the boundaries of the OB fold DNA-binding domain using deletion mutants. Since Leishmania and other trypanosomatids lack homologues of known telomere end binding proteins, our results raise questions about the function of RPA-1 in parasite telomeres.
authors.affiliation: Departamento de Genética, Instituto de Biociências, Universidade Estadual de São Paulo, UNESP, 18618-000 Botucatu, SP, Brazil.
authors.forename: J L Siqueira
authors.initials: JL
authors.lastname: Neto
authors.forename: C B B
authors.initials: CB
authors.lastname: Lira
authors.forename: M A
authors.initials: MA
authors.lastname: Giardini
authors.forename: L
authors.initials: L
authors.lastname: Khater
authors.forename: A M
authors.initials: AM
authors.lastname: Perez
authors.forename: L A
authors.initials: LA
authors.lastname: Peroni
authors.forename: J R R
authors.initials: JR
authors.lastname: dos Reis
authors.forename: L H
authors.initials: LH
authors.lastname: Freitas-Junior
authors.forename: C H I
authors.initials: CH
authors.lastname: Ramos
authors.forename: M I N
authors.initials: MI
authors.lastname: Cano
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D004247:DNA / Q000737:chemistry* / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D007891:Leishmania / Q000502:physiology*; D008969:Molecular Sequence Data; D011485:Protein Binding; D051716:Replication Protein A / Q000737:chemistry* / Q000378:metabolism*; D016615:Telomere / Q000235:genetics*
chemical_list: D004268:DNA-Binding Proteins; D051716:Replication Protein A; D004247:DNA