The immunoglobulin kappa light chain intronic enhancer (iEkappa) activates kappa rearrangement and is required to maintain the earlier or more efficient rearrangement of kappa versus lambda (lambda). To understand the mechanism of how iEkappa regulates kappa rearrangement, we employed homologous recombination to mutate individual functional motifs within iE(kappa) in the endogenous kappa locus,...

We detected a rearrangement in the N-myc gene region in a neuroblastoma from a 9-month-old girl. In this case, the N-myc gene was amplified 50-fold in the primary tumor, the lymph node metastasis, and the hepatic metastasis. The rearrangement was detected only in the primary tumor and the lymph node metastasis, whereas N-myc RNA and protein expression were detected only in the primary tumor and...

The classical Hausdorff-Young theorem is extended to the setting of rearrangement-invariant spaces. More precisely, if 1 ^ V ̂ 2, p~ + q= 1, and if X is a rearrangement-invariant space on the circle T with indices equal to p~ι9 it is shown that there is a rearrangement-invariant space X on the integers Z with indices equal to ςr such that the Fourier transform is a bounded linear operator from X...

The study of genome rearrangement is much harder than the corresponding problems on DNA and protein sequences, because of the occurrences of numerous combinatorial structures. By explicitly exploring these combinatorial structures, the recently developed adequate subgraph theory shows that a family of these structures, adequate subgraphs, are informative in finding the optimal solutions to the ...

Somatic rearrangement of immunoglobulin (Ig) genes is a key step during B cell development. Using pro-B cells lacking the phosphatase Pten (phosphatase and tensin homolog), which negatively regulates phosphoinositide-3-kinase (PI3K) signaling, we show that PI3K signaling inhibits Ig gene rearrangement by suppressing the expression of the transcription factor Ikaros. Further analysis revealed th...

The human pre-B acute lymphoblastic leukemia cell line, BLIN-1, has been previously shown to undergo kappa light chain rearrangement in vitro, making it a valuable resource for analyzing pre-B to B cell differentiation. We have examined the recombination potential of BLIN-1 by characterizing several independently derived kappa-expressing subclones for DNA rearrangement and V kappa gene usage. A...

Glioblastoma multiforme (GBM) is the most aggressive type of brain tumor, and the prognosis remains poor. Rearrangement of ROS1 gene, which was shown to have an oncogenic potential, was previously discovered in GBM cell lines. In this pilot study, we aimed to identify the incidence of ROS1 rearrangement in GBM patient tissues to explore novel biomarkers for therapeutic strategy. Formalin-fixed ...

Analysis of TCR rearrangement profiles of well-defined thymocyte populations in a number of individual thymi provides evidence for a new pathway of lineage commitment. In all of the thymi analyzed, alphabeta thymocytes have rearrangements in the delta locus that are enhanced for out-of-frame rearrangements. Thus, not only did alphabeta thymocytes pass through a stage in differentiation that inc...

Continued antibody gene rearrangement, termed receptor editing, is an important mechanism of central B cell tolerance that may be defective in some autoimmune individuals. We describe a quantitative assay for recombining sequence (RS) rearrangement that we use to estimate levels of antibody light chain receptor editing in various B cell populations. RS rearrangement is a recombination of a nonc...

Immunophenotyping disclosed CD10 negativity in 70 of 2,408 cases of B-lineage acute lymphoblastic leukemia (ALL), although other criteria followed classification of pre-B ALL (e.g., cytoplasmic immunoglobulin positivity). These blasts showed high myeloid antigen expression (60% CD65-positivity) and reacted with antibody 7.1 in 95% of the cases. MLL-AF4 fusion transcripts and/or an 11q23/MLL rea...