Shima-Rich E A, Harden A M, McKeithan T W, Rowley J D, Diaz M O
Department of Pathology, University of Chicago, Illinois, USA.
Genes Chromosomes Cancer. 1997 Dec;20(4):363-71. doi: 10.1002/(sici)1098-2264(199712)20:4<363::aid-gcc7>3.0.co;2-#.
The MOLT-16 cell line was established from the leukemic cells of a patient with T-cell acute lymphoblastic leukemia and contains a t(8;14)(q24;q11) resulting in juxtaposition of sequences downstream of the MYC gene on chromosome 8 and the J region of the T-cell receptor alpha chain gene (TCRA) on chromosome 14. The reciprocal translocation involved a complex rearrangement with two chromosome breakpoints within the TCRAJ region on chromosome 14, resulting in inversion of a 1.4 kb DNA fragment between the two breakpoints. The 5' border of the inversion joints with another segment of chromosome 14, whereas the 3' border joins with a region of chromosome 8 located at least 257 kb downstream of MYC. Extensive deletions have occurred on both chromosomes 8 and 14 in conjunction with the translocation. To investigate the possible involvement of the V(D)J recombinase in this translocation, we analyzed the nucleotide sequences surrounding the translocation breakpoints. The breakpoint on chromosome 14 occurs between a segment coding for a TCRAJ sequence and its hepatamer-nonamer signal. Heptamer-nonamer consensus sequences are also identified on chromosome 8 adjacent to the breakpoint. Inserted N and P nucleotides are observed at the breakpoint junctions.
MOLT-16细胞系源自一名T细胞急性淋巴细胞白血病患者的白血病细胞，含有t(8;14)(q24;q11)，导致8号染色体上MYC基因下游的序列与14号染色体上T细胞受体α链基因（TCRA）的J区域并列。相互易位涉及复杂重排，在14号染色体的TCRAJ区域内有两个染色体断点，导致两个断点之间1.4 kb DNA片段发生倒位。倒位的5'边界与14号染色体的另一段相连，而3'边界与8号染色体上位于MYC下游至少257 kb的区域相连。8号和14号染色体上均发生了广泛的缺失，与易位同时出现。为了研究V(D)J重组酶在这种易位中可能的作用，我们分析了易位断点周围的核苷酸序列。14号染色体上的断点出现在编码TCRAJ序列的片段与其七聚体-九聚体信号之间。在8号染色体上靠近断点处也鉴定出七聚体-九聚体共有序列。在断点连接处观察到插入的N和P核苷酸。
