Structural basis for DNA binding by replication initiator Mcm10.
Mcm10 is an essential eukaryotic DNA replication protein required for assembly and progression of the replication fork. The highly conserved internal domain (Mcm10-ID) has been shown to physically interact with single-stranded (ss) DNA, DNA polymerase alpha, and proliferating cell nuclear antigen (PCNA). The crystal structure of Xenopus laevis Mcm10-ID presented here reveals a DNA binding architecture composed of an oligonucleotide/oligosaccharide-fold followed in tandem by a variant and highly basic zinc finger. NMR chemical shift perturbation and mutational studies of DNA binding activity in vitro reveal how Mcm10 uses this unique surface to engage ssDNA. Corresponding mutations in Saccharomyces cerevisiae result in increased sensitivity to replication stress, demonstrating the functional importance of DNA binding by this region of Mcm10 to replication. In addition, mapping Mcm10 mutations known to disrupt PCNA, polymerase alpha, and DNA interactions onto the crystal structure provides insight into how Mcm10 might coordinate protein and DNA binding within the replisome.
Warren
Eric M
EM
Department of Biological Sciences, Vanderbilt University, Nashville, TN 37232, USA.
Vaithiyalingam
Sivaraja
S
Haworth
Justin
J
Greer
Briana
B
Bielinsky
Anja-Katrin
AK
Chazin
Walter J
WJ
Eichman
Brandt F
BF
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D055592:Biophysical Phenomena; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D004252:DNA Mutational Analysis; D004256:DNA Polymerase I / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000737:chemistry*; D064110:Minichromosome Maintenance Proteins; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D019906:Nuclear Magnetic Resonance, Biomolecular; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D016335:Zinc Fingers / Q000235:genetics
D004268:DNA-Binding Proteins; C527642:Mcm10 protein, Xenopus; D018809:Proliferating Cell Nuclear Antigen; D029701:Saccharomyces cerevisiae Proteins; D004247:DNA; D004256:DNA Polymerase I; D064110:Minichromosome Maintenance Proteins