ATP-facilitated chromatin assembly with a nucleoplasmin-like protein from Drosophila melanogaster.
To gain a better understanding of the factors that can mediate chromatin assembly, we have purified and cloned a core histone-binding protein from Drosophila melanogaster embryos. This protein resembles Xenopus laevis nucleoplasmin, and it has therefore been termed dNLP, for Drosophila nucleoplasmin-like protein. dNLP is a nuclear protein that is present throughout development. Both purified native and recombinant dNLP bind to core histones and can function in the assembly of approximately regularly spaced nucleosomal arrays in a reaction that additionally requires DNA, purified core histones, ATP, and a partially purified fraction (containing at least one other assembly activity). We also analyzed the properties of an N-terminally truncated version of dNLP, termed dNLP-S, and found that the deletion of the N-terminal 31 residues of dNLP results in a loss of the specificity of the interaction of dNLP with core histones. We then compared the abilities of dNLP and Drosophila nucleosome assembly protein-1 (dNAP-1) to promote the decondensation of Xenopus sperm chromatin, a process that can be mediated by nucleoplasmin. We observed that dNAP-1, but not dNLP, was able to promote the decondensation of sperm chromatin. These and other data collectively suggest that dNLP may participate in parallel with other histone-binding proteins such as dNAP-1 in the assembly of chromatin.
Ito
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Department of Biology and Center for Molecular Genetics, University of California, San Diego, La Jolla, California 92093-0347, USA.
Tyler
J K
JK
Bulger
M
M
Kobayashi
R
R
Kadonaga
J T
JT
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002843:Chromatin / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000196:embryology / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D056489:Nucleoplasmins; D010750:Phosphoproteins; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000378:metabolism
D002843:Chromatin; D018076:DNA, Complementary; D029721:Drosophila Proteins; D006657:Histones; C533549:Nlp protein, Drosophila; D009687:Nuclear Proteins; D056489:Nucleoplasmins; D010750:Phosphoproteins; D000255:Adenosine Triphosphate