Leishmania replication protein A-1 binds in vivo single-stranded telomeric DNA.
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.
Neto
J L Siqueira
JL
Departamento de Genética, Instituto de Biociências, Universidade Estadual de São Paulo, UNESP, 18618-000 Botucatu, SP, Brazil.
Lira
C B B
CB
Giardini
M A
MA
Khater
L
L
Perez
A M
AM
Peroni
L A
LA
dos Reis
J R R
JR
Freitas-Junior
L H
LH
Ramos
C H I
CH
Cano
M I N
MI
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*
D004268:DNA-Binding Proteins; D051716:Replication Protein A; D004247:DNA