Analysing the contribution of nucleic acids to the structure and properties of centric heterochromatin.
A class of repetitive DNA sequences frequently found at centromeric regions are R/Y-satellites showing an asymmetric distribution of residues resulting in one strand being rich in purines (R-strand) while the complementary strand is pyrimidine-rich (Y-strand). The dodeca-satellite of Drosophila belongs to this class of centromeric satellites. In vitro, the dodeca-satellite forms altered DNA structures in which the R-strand forms very stable intramolecular fold-backs that are stabilised by the formation of tandem G x A mismatches. A single-stranded nucleic acids binding protein, DDP1, binds the unstructured dodeca-satellite Y-strand with high affinity. In polytene chromosomes, DDP1 associates with the heterochromatic chromocenter and, at the euchromatic chromosome arms, co-localises with HP1. DDP1 is a vigilin. Vigilins are highly conserved multi-KH-domain proteins. Scp160p, the vigilin from S. cerevisiae, is involved in the control of ploidy. DDP1 complements a deltascp160 deletion.
Departament de Biologia Molecular i Cellular, Institut de Biologia Molecular de Barcelona, CSIC, Jordi Girona Salgado, 18-26, 08034, Barcelona, Spain.
Alfred
A
Cortés
Dori
D
Huertas
Francesc X
FX
Marsellach
Neus
N
Ferrer-Miralles
Miguel
M
Ortiz-Lombardía
Laura
L
Fanti
Sergio
S
Pimpinelli
Benjami
B
Piña
Fernando
F
Azorín
D000595:Amino Acid Sequence; D000818:Animals; D020029:Base Pairing / Q000235:genetics; D002352:Carrier Proteins; D002503:Centromere; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics*; D004276:DNA, Satellite / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D006570:Heterochromatin / Q000235:genetics*; D026901:Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D008969:Molecular Sequence Data; D016601:RNA-Binding Proteins / Q000235:genetics
D002352:Carrier Proteins; D004276:DNA, Satellite; D004268:DNA-Binding Proteins; C491076:Dp1 protein, Drosophila; D029721:Drosophila Proteins; D006570:Heterochromatin; D026901:Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D016601:RNA-Binding Proteins; C118122:TIMM8A protein, human; C075197:high density lipoprotein binding protein; D004247:DNA