Remodeling sperm chromatin in Xenopus laevis egg extracts: the role of core histone phosphorylation and linker histone B4 in chromatin assembly.
We find that the remodeling of the condensed Xenopus laevis sperm nucleus into the paternal pronucleus in egg extracts is associated with phosphorylation of the core histones H2A, H2A.X and H4, and uptake of a linker histone B4 and a HMG 2 protein. Histone B4 is required for the assembly of chromatosome structures in the pronucleus. However neither B4 nor core histone phosphorylation are required for the assembly of spaced nucleosomal arrays. We suggest that the spacing of nucleosomal arrays is determined by interaction between adjacent histone octamers under physiological assembly conditions.
Dimitrov
S
S
Laboratory of Molecular Embryology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892.
Dasso
M C
MC
Wolffe
A P
AP
D000818:Animals; D001483:Base Sequence; D002457:Cell Extracts; D002843:Chromatin / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D004261:DNA Replication; D006657:Histones / Q000378:metabolism*; D015151:Immunoblotting; D008297:Male; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism*; D010766:Phosphorylation; D013094:Spermatozoa / Q000378:metabolism*; D014982:Xenopus laevis
D002457:Cell Extracts; D002843:Chromatin; D006657:Histones; D009707:Nucleosomes; D004247:DNA