DNA replication (DNA synthesis)
The process by which a DNA molecule is copied.
(1) The conversion of a normal animal cell to a cancerous cell (2) A change in genotype and phenotype due to the assimilation of external DNA by a cell. When the external DNA is from a member of a different species, this results in horizontal gene transfer.
A virus that infects bacteria; also called a phage.
A virus that infects bacteria; also called a bacteriophage.
The form of native DNA, referring to its two adjacent antiparallel polynucleotide strands wound around an imaginary axis into a spiral shape.
Reffering to the arrangment of the sugar-phosphate backbones in a DNA double helix (they run in opposite 5' → 3' directions).
Type of DNA replication in which the replicated double helix consists of one old strand, derived form the parental molecule, and one newly made strand.
origin of replication
Site where the replication of a DNA molecule begins, consisting of a specific sequence of nucleotides.
A Y-shaped region on a replicating DNA molecule where the parental strands are being unwound and new strands are being synthesized.
An enzyme that untwists the double helix of DNA at replication forks, separating the two strands and making them available as template strands.
single-strand binding protein
A protein that binds to the unpaired DNA strands during DNA replication, stabilizing them and holding them apart while they serve as templates for the synthesis of complementary strands of DNA.
A protein that breaks, swivels, and rejoins DNA strands. During DNA replication, topoisomerase helps to relieve strain in the double helix ahead of the replication fork.
A short stretch of RNA with a free 3' end, bound by complementary base pairing to the template strand and elongated with DNA nucleotides during DNA replication.
An enzyme that joins RNA nucleotides to make a primer during DNA replication, using the parental DNA strand as a template.
An enzyme that catalyzes the elongation of new DNA (for example, at a replication fork) by the addition of nucleotides to the 3' end of an existing chain. There are several different ones.
The new complementary DNA strand synthesized continuously along the template strand toward the replication fork in the mandatory 5' → 3' direction.
A discontinuously synthesized DNA strand that elongates by means of Okazaki fragments, each synthesized in a 5' → 3' direction away from the replication fork.
A short segment of DNA synthesize away from the replication fork on a template strand during DNA replication. Many such segments are joined together to make up the lagging strand of newly synthesized DNA.
A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of one DNA fragment (such as an Okazaki fragment) to the 5' end of another DNA fragment (such as a growing DNA chain).
The cellular process that uses specific enzymes to remove and replace incorrectly paired nucleotides.
An enzyme that cuts DNA or RNA, either removing one or a few bases or hydrolyzing the DNA or RNA completely into its component nucleotides.
nucleotide excision repair
A repair system that removes and then correctly replaces a damaged segment of DNA using the undamaged strand as a guide.
The tandemly repetitive DNA at the end of a eukaryotic chromosome's DNA molecule. They protect the organism's genes from being eroded during successive rounds of replication.
An enzyme that catalyzes the lengthening of telomeres in eukaryotic germ cells.
A non-membrane-bounded region in a prokaryotic cell where the DNA is concentrated.
The complex of DNA and proteins that makes up eukaryotic chromosomes. When the cell is not dividing, it exists in its dispersed form, as a mass of very long, thin fibers that are not visible with a light microscope.
A small protein with a high proportion of positively charged amino acids that binds to the negatively charged DNA and plays a key role in chromatin structure.
The basic, bead-like unit of DNA packing in eukaryotes, consisting of a segment of DNA wound around a protein core composed of two copies of each of four types of histone.
Eukaryotic chromatin that remains highly compacted during interphase and is generally not transcribed.
The less condensed form of eukaryotic chromatin that is available for transcription.