title: Trypanosoma cruzi histone H1 is phosphorylated in a typical cyclin dependent kinase site accordingly to the cell cycle.
abstract: Histone H1 of most eukaryotes is phosphorylated during the cell cycle progression and seems to play a role in the regulation of chromatin structure, affecting replication and chromosome condensation. In trypanosomatids, histone H1 lacks the globular domain and is shorter when compared with the histone of other eukaryotes. We have previously shown that in Trypanosoma cruzi, the agent of Chagas' disease, histone H1 is phosphorylated and this increases its dissociation from chromatin. Here, we demonstrate using mass spectrometry analysis that T. cruzi histone H1 is only phosphorylated at the serine 12 in the sequence SPKK, a typical cyclin-dependent kinase site. We also found a correlation between the phosphorylation state of histone H1 and the cell cycle. Hydroxyurea and lactacystin, which, respectively, arrest parasites at the G1/S and G2/M stages of the cell cycle, increased the level of histone H1 phosphorylation. Cyclin-dependent kinase-related enzymes TzCRK3, and less intensely the TzCRK1 were able to phosphorylate histone H1 in vitro. Histone H1 dephosphorylation was prevented by treating the parasites with okadaic acid but not with calyculin A. These findings suggest that T. cruzi histone H1 phosphorylation is promoted by cyclin dependent kinases, present during S through G2 phase of the cell cycle, and its dephosphorylation is promoted by specific phosphatases.
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, R. Botucatu 862-8(a), EPM-UNIFESP, São Paulo, SP 04023-062, Brazil.
authors.forename: Julia Pinheiro Chagas
authors.initials: JP
authors.lastname: da Cunha
authors.forename: Ernesto S
authors.initials: ES
authors.lastname: Nakayasu
authors.forename: Maria Carolina
authors.initials: MC
authors.lastname: Elias
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Pimenta
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Téllez-Iñón
authors.forename: Federico
authors.initials: F
authors.lastname: Rojas
authors.forename: Manuel J
authors.initials: MJ
authors.lastname: Muñoz
authors.forename: Muñoz
authors.initials: M
authors.lastname: Manuel
authors.forename: Igor C
authors.initials: IC
authors.lastname: Almeida
authors.forename: Sergio
authors.initials: S
authors.lastname: Schenkman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D016203:CDC2 Protein Kinase; D002453:Cell Cycle; D002460:Cell Line; D018844:Cyclin-Dependent Kinases / Q000378:metabolism* / Q000494:pharmacology; D006657:Histones / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D019319:Okadaic Acid / Q000494:pharmacology; D010766:Phosphorylation; D015800:Protozoan Proteins; D016415:Sequence Alignment; D014349:Trypanosoma cruzi / Q000378:metabolism*
chemical_list: D006657:Histones; D015800:Protozoan Proteins; D019319:Okadaic Acid; D016203:CDC2 Protein Kinase; D018844:Cyclin-Dependent Kinases