title: Developmental expression pattern of histone H4 gene associated to DNA synthesis in the endoparasitic platyhelminth Mesocestoides corti.
abstract: In higher eukaryotes, histone gene expression is coupled to DNA replication during the S-phase of the cell cycle. This coupling is primarily controlled at the transcriptional level. Considering the basal phylogenic position of platyhelminthes in the bilateria phylum, we have cloned a partial sequence of the histone H4 gene of Mesocestoides corti and studied its expression during the post larval development of this endoparasitic platyhelminth. In in vitro trypsin-induced tetrathyridia development to segmented adult worm, we found that histone H4 is expressed concomitantly with DNA synthesis throughout all stages of development. DNA synthesis and histone H4 mRNA levels were sharply increased at 24 h after inducing development. Afterwards, tetrathyridia grew in length from days 4 to 12 of development as proliferative cells gradually increased in number. Consequently, during this period of development histone H4 mRNA levels were upregulated. Taken together these results suggest that a replication-dependent expression pattern of histone H4 occurs in ancient bilateria, such as platyhelminthes, as previously observed in higher eukaryotes.
authors.affiliation: Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (I.C.B.M.), Facultad de Medicina, Universidad de Chile, 8389100 Independencia, Santiago, Chile.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Espinoza
authors.forename: Christian R
authors.initials: CR
authors.lastname: Gomez
authors.forename: Mario
authors.initials: M
authors.lastname: Galindo
authors.forename: Norbel
authors.initials: N
authors.lastname: Galanti
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004261:DNA Replication / Q000502:physiology*; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D015801:Helminth Proteins / Q000096:biosynthesis / Q000235:genetics; D006657:Histones / Q000096:biosynthesis* / Q000235:genetics*; D008297:Male; D008645:Mesocestoides / Q000196:embryology / Q000235:genetics* / Q000254:growth & development; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data
chemical_list: D015801:Helminth Proteins; D006657:Histones