Purification and characterization of a mitochondrial DNA-binding protein that binds to double-stranded and single-stranded sequences of Paracentrotus lividus mitochondrial DNA.
A mitochondrial protein, able to specifically bind two double-stranded homologous sequences of sea-urchin mitochondrial DNA, has been partially purified from Paracentrotus lividus eggs. This protein, present at a low concentration, is a polypeptide of 40 kDa. One of the binding sequences, located in the main non-coding region, contains the replication origin of the mitochondrial DNA H-strand. By a combination of band-shift, DNase footprinting, and modification interference analyses with homologous and heterologous probes we identified YCYYATCAN(A/T)RC as the minimum sequence required for the binding. The protein also shows a single-stranded DNA-binding activity, as it is able to specifically interact with one of the strands of the binding sites. These features are consistent with a function of the protein in the modulation of sea-urchin mitochondrial DNA replication during the development stages.
Polosa
P L
PL
Dipartimento di Biochimica e Biologia Molecolare, Università di Bari, Italy.
Roberti
M
M
Mustich
A
A
Gadaleta
M N
MN
Cantatore
P
P
D000818:Animals; D001483:Base Sequence; D004261:DNA Replication; D004272:DNA, Mitochondrial / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000302:isolation & purification* / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D012617:Sea Urchins / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D004272:DNA, Mitochondrial; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins