anneal

1. To soften or temper a metal by controlled heating and cooling; the process makes a metal more easily adapted, bent, or swaged, and less brittle. 2. In dentistry, to heat gold leaf preparatory to its insertion into a cavity, in order to remove adsorbed gases and other contaminants. 3. The pairing of complementary single strands of DNA; or of DNA-RNA. 4. The attachment of the ends of two macromolecules; e.g., two microtubules annealing to form one longer microtubule. 5. In molecular biology, annealing is a process in which short sections of single-stranded DNA from one source are bound to a filter and incubated with single-stranded, radioactively conjugated DNA from a second source. Where the two sets of DNA possess complementary sequences of nucleotides, bonding occurs. The degree of relatedness (homology) of the two sets of DNA is then estimated according to the radioactivity level of the filter. This technique plays a central role in the classification of bacteria and viruses. SYN: nucleic acid hybridization. [A.S. anaelan, to burn]

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an·neal ə-'nē(ə)l vt

1) to heat and then cool (as steel or glass) usu. for softening and making less brittle

2) to heat and then cool (double-stranded nucleic acid) in order to separate strands and induce combination at lower temperatures esp. with complementary strands vi to be capable of combining with complementary nucleic acid by a process of heating and cooling <some bacterial nucleic acid \anneals well with eukaryotic DNA>

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an·neal (ə-nēlґ) 1. to heat a material, such as glass or metal, followed by controlled cooling to remove internal stresses and induce a desired degree of toughness, temper, or softness of the material. 2. to homogenize an amalgam alloy ingot by heating it in an oven. 3. to degas; see degassing (def. 2). 4. in molecular biology, to cause the association or reassociation of single-stranded nucleic acids so that double-stranded molecules are formed, often by heating followed by cooling.