Pericentric heterochromatin reprogramming by new histone variants during mouse spermiogenesis.
During male germ cell postmeiotic maturation, dramatic chromatin reorganization occurs, which is driven by completely unknown mechanisms. For the first time, we describe a specific reprogramming of mouse pericentric heterochromatin. Initiated when histones undergo global acetylation in early elongating spermatids, this process leads to the establishment of new DNA packaging structures organizing the pericentric regions in condensing spermatids. Five new histone variants were discovered, which are expressed in late spermiogenic cells. Two of them, which we named H2AL1 and H2AL2, specifically mark the pericentric regions in condensing spermatids and participate in the formation of new nucleoprotein structures. Moreover, our investigations also suggest that TH2B, an already identified testis-specific H2B variant of unknown function, could provide a platform for the structural transitions accompanying the incorporation of these new histone variants.
Govin
Jérôme
J
Institut National de la Santé et de la Recherche Médicale, U309, Institut Albert Bonniot, F-38700 Grenoble, France.
Escoffier
Emmanuelle
E
Rousseaux
Sophie
S
Kuhn
Lauriane
L
Ferro
Myriam
M
Thévenon
Julien
J
Catena
Raffaella
R
Davidson
Irwin
I
Garin
Jérôme
J
Khochbin
Saadi
S
Caron
Cécile
C
D000107:Acetylation; D000595:Amino Acid Sequence; D000818:Animals; D019281:Dimerization; D006570:Heterochromatin / Q000502:physiology*; D006657:Histones / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008540:Meiosis / Q000502:physiology; D051379:Mice; D008969:Molecular Sequence Data; D009698:Nucleoproteins / Q000502:physiology; D013087:Spermatids / Q000166:cytology / Q000502:physiology; D013091:Spermatogenesis / Q000502:physiology*
D006570:Heterochromatin; D006657:Histones; D009698:Nucleoproteins