How do checkpoint proteins Rad9 and Hus1 act to maintain genome stability in the protozoan Leishmania major?

Abstract

Our laboratory has contributed to the understanding of DNA damage signaling pathways in the protozoan parasite Leishmania. The study of the detection and signaling of DNA damage in an early-diverging eukaryote can further our understanding of how DNA Damage Response (DDR) has been established in the eukaryotic line. Based on the identification and characterization of checkpoint proteins Rad9 and Hus1 in Leishmania, reported by our group, we intend to investigate the involvement of these proteins in more specific aspects of the peculiar biology of these organisms. Thus, the general objective of this proposal is (i) to use deficient or null cell lines for Rad9 or Hus1 to characterize the role of these proteins in the control of copy numbers in the L. major genome; (ii) to use ChIP and ChIP-seq to investigate the complexes containing Hus1 or Rad9 and the loci to which Hus1 associates in L. major in response to replicative stress; and (iii) to use truncated versions of Rad9 from L. major to characterize the role of its C-terminal domain. (AU)