Grawunder U, West R B, Lieber M R
Department of Pathology, University of Southern California School of Medicine, Los Angeles 90033, USA.
Curr Opin Immunol. 1998 Apr;10(2):172-80. doi: 10.1016/s0952-7915(98)80246-x.
Two specialized forms of site-directed double-strand (ds) DNA breakage and rejoining are part of the physiologic program of lymphocytes. One is recombination of the V, D and J gene sequences, termed V(D)J recombination, occurring during early B- and T-cell development, and the other is class-switch recombination occurring exclusively in mature B cells. For V(D)J recombination significant progress has been made recently elucidating the biochemistry of the reaction. In particular our understanding of how DNA ds breaks are both generated and rejoined has increased. For class-switch recombination no definitive information is known about the nucleases required for making the ds breaks, but recent evidence suggests that the joining phase shares activities also required for V(D)J recombination and general DNA ds break repair.
位点特异性双链（ds）DNA断裂与重新连接的两种特殊形式是淋巴细胞生理程序的一部分。一种是V、D和J基因序列的重组，称为V（D）J重组，发生在早期B细胞和T细胞发育过程中；另一种是类别转换重组，仅发生在成熟B细胞中。对于V（D）J重组，最近在阐明该反应的生物化学方面取得了重大进展。特别是，我们对DNA双链断裂如何产生和重新连接的理解有所增加。对于类别转换重组，关于产生双链断裂所需的核酸酶尚无确切信息，但最近的证据表明，连接阶段具有V（D）J重组和一般DNA双链断裂修复所需的共同活性。
