DNA-binding activity of the C2 protein of tomato yellow leaf curl geminivirus.
The in vitro DNA-binding activity of the C2 protein of tomato yellow leaf curl geminivirus (TYLCV) was studied following its expression in Escherichia coli as a fusion protein with an His tag N-terminal extension (His-C2). Southwestern blotting experiments demonstrated that the C2 protein is able to bind both single-stranded and double-stranded DNA probes. In electrophoretic mobility shift assays performed using purified protein and single-stranded DNA probes several shifted complexes were formed. The presence of NaCl (up to 800 mM) did not substantially affect binding profiles, demonstrating a stable interaction. His-C2 appeared to bind single-stranded DNA in a sequence-nonspecific manner, with a preference for single-stranded compared to double-stranded DNA. Deletion mutants demonstrated that the central core of C2 (amino acids 33 to 104), which contains a Cys-His rich region, is sufficient for conferring binding activity. The potential significance of this DNA-binding activity with respect to possible biological functions of TYLCV C2 protein is discussed.
Noris
E
E
Istituto di Fitovirologia Applicata, CNR, Torino, Italy.
Jupin
I
I
Accotto
G P
GP
Gronenborn
B
B
D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism*; D017791:Geminiviridae / Q000235:genetics*; D018551:Solanum lycopersicum; D008969:Molecular Sequence Data; D014764:Viral Proteins / Q000378:metabolism*
D017931:DNA Primers; D004268:DNA-Binding Proteins; D014764:Viral Proteins