Several ligands can bind to the non-canonical G-quadruplex DNA structures thereby stabilizing them. These molecules can act as effective anticancer agents by stabilizing the telomeric regions of DNA or by regulating oncogene expression. In order to better interact with the quartets of G-quadruplex structures, G-binders are generally characterized by a large aromatic core involved in π-π stackin...

T o prevent chromosome segregation errors, cytokinesis in Saccharomyces cerevisiae awaits the arrival of a spindle pole body (SPB) in the bud. On page 335 , Fraschini et al. show that this arrival is announced by the mother-bound SPB, which heralds the onset of cytokinesis and mitotic exit. Mitotic exit relies on a G-protein called Tem1, which activates the destruction of mitotic cyclins. As Te...

INTRODUCTION The enhancement of peak power by means of RF pulse compression has found important application for driving high energy electron linacs, the SLAC linac in particular. The SLAC Energy Doubler [l] (SLED), however, yields a pulse shape in the form of a decaying exponential which lim its the applicability of the method. Two methods of improving this situation have been suggested: binary...

T elomeres are unique protein–DNA structures that comprise the termini of eukaryotic linear chromosomes (for review see references 1, 2). Telomeric DNA does not contain protein-encoding genes but rather consists of G-rich hexanu-cleotide repeats that in vertebrate cells are (TTAGGG) n sequences. Based on studies initially carried out in yeast and other single cell organisms, it appears that tel...

T elomeres are unique protein–DNA structures that comprise the termini of eukaryotic linear chromosomes (for review see references 1, 2). Telomeric DNA does not contain protein-encoding genes but rather consists of G-rich hexanu-cleotide repeats that in vertebrate cells are (TTAGGG) n sequences. Based on studies initially carried out in yeast and other single cell organisms, it appears that tel...

Every time a cell divides, it must duplicate and segregate its chromosomes. Eukaryotic cells carry out these processes with remarkable order and fidelity. For example, in the yeast Saccharomyces cerevisiae, chromosome loss occurs at rates of only-10-5 per cell division. This precision is achieved at four levels. First, chromosomes bear replication origins, centromeres, and telomeres, cis-acting...

Klebba and Galletta et al. reveal that the scaffold protein Asterless (Asl) regulates centriole duplication by controlling turnover of the kinase Plk4. Cells must duplicate their centri-oles once, and only once, per cell cycle. In interphase, the master regulator of centriole duplication, Plk4, triggers its own destruction by homodimerizing and phosphorylating itself. In mitosis, however, the p...

can be inferred in many more species on the basis of characteristic repetitive G-rich telomeric DNA sequences. The near universality of telomerase in eukaryotic species is striking because there are many other solutions, such as protein priming, terminal hairpins, and recombina-Boulder, Colorado 80309-0215 tion, that ensure complete replication of linear DNA in viral and bacterial plasmid genom...