Coding sequence composition flanking either signal element alters V(D)J recombination efficiency.
نویسندگان
چکیده
Lymphoid V(D)J rearrangement is targeted by recombination signal sequences (RSS) bordering V, D or J exons. We demonstrate that the DNA composition of flanking coding positions, particularly poly(A) or poly(T) stretches at one or both RSS, diminishes V(D)J recombination up to 100-fold. Positionally correct cleavages occur in the inhibited reactions, since the junctions formed show the same frequency of precision as uninhibited reactions. Open/shut cleavage/rejoining is not increased at a normal RSS in substrates containing inhibitory A/T homopolymers versus random sequence at a second RSS. Thus recombinase action at both cleavage sites is severely disrupted by modified coding sequences.
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ورودعنوان ژورنال:
- Nucleic acids research
دوره 23 6 شماره
صفحات -
تاریخ انتشار 1995