TY - JOUR
T1 - The histone H3.3 chaperone HIRA is essential for chromatin assembly in the male pronucleus
AU - Loppin, Benjamin
AU - Bonnefoy, Emilie
AU - Anselme, Caroline
AU - Laurencon, Anne
AU - Karr, Timothy L.
AU - Couble, Pierre
N1 - ID number: ISI:000232829100060
PY - 2005/10/27
Y1 - 2005/10/27
N2 - In sexually reproducing animals, a crucial step in zygote formation is the decondensation of the fertilizing spermnucleus into a DNA replication-competent male pronucleus. Genome-wide nucleosome assembly on paternal DNA implies the replacement of sperm chromosomal proteins, such as protamines, by maternally provided histones(1,2). This fundamental process is specifically impaired in sesame (ssm), a unique Drosophila maternal effect mutant that prevents male pronucleus formation(3). Here we show that ssm is a point mutation in the Hira gene, thus demonstrating that the histone chaperone protein HIRA is required for nucleosome assembly during sperm nucleus decondensation. In vertebrates, HIRA has recently been shown to be critical for a nucleosome assembly pathway independent of DNA synthesis that specifically involves the H3.3 histone variant(4,5). We also show that nucleosomes containing H3.3, and not H3, are specifically assembled in paternal Drosophila chromatin before the first round of DNA replication. The exclusive marking of paternal chromosomes with H3.3 represents a primary epigenetic distinction between parental genomes in the zygote, and underlines an important consequence of the critical and highly specialized function of HIRA at fertilization.
AB - In sexually reproducing animals, a crucial step in zygote formation is the decondensation of the fertilizing spermnucleus into a DNA replication-competent male pronucleus. Genome-wide nucleosome assembly on paternal DNA implies the replacement of sperm chromosomal proteins, such as protamines, by maternally provided histones(1,2). This fundamental process is specifically impaired in sesame (ssm), a unique Drosophila maternal effect mutant that prevents male pronucleus formation(3). Here we show that ssm is a point mutation in the Hira gene, thus demonstrating that the histone chaperone protein HIRA is required for nucleosome assembly during sperm nucleus decondensation. In vertebrates, HIRA has recently been shown to be critical for a nucleosome assembly pathway independent of DNA synthesis that specifically involves the H3.3 histone variant(4,5). We also show that nucleosomes containing H3.3, and not H3, are specifically assembled in paternal Drosophila chromatin before the first round of DNA replication. The exclusive marking of paternal chromosomes with H3.3 represents a primary epigenetic distinction between parental genomes in the zygote, and underlines an important consequence of the critical and highly specialized function of HIRA at fertilization.
UR - http://dx.doi.org/10.1038/nature04059
U2 - 10.1038/nature04059
DO - 10.1038/nature04059
M3 - Article
SN - 0028-0836
VL - 437
SP - 1386
EP - 1390
JO - Nature
JF - Nature
IS - 7063
ER -