The mre11A470T mutation and homeologous interactions increase error-prone BIR.

In the absence of the RNA-templated reverse transcriptase, telomerase, the predominant means of terminal addition, arises from break-induced replication (BIR) at multiple homologous subtelomeric Y' loci and among internal homeologous (imperfect) (polyG1-3T) tracts. These last tracts are interspersed between subtelomeric Y' direct repeats. One major survivor class contains very short (~50 bp) terminal telomere repeats.

The louisiana clinical data research network: leveraging regional and national resources to improve clinical research efficiency.

Background: Mapping of the human genome and technological advancements allowing storage and rapid retrieval of healthcare data have heralded a new phase in clinical medicine and have served as a catalyst for the advent of personalized medicine. The use of health information databases provides a unique opportunity to investigate questions of great complexity and real-world application in a way that is most useful in providing high quality, safe, and cost-effective clinical care to patients.

Methods: The Louisiana Clinical Data Research Network (LACDRN) aims to streamline the workflow of multiinstitutional clinical studies and to dramatically expand the clinical research resources available to local investigators.

The Ctf18RFC clamp loader is essential for telomere stability in telomerase-negative and mre11 mutant alleles.

The function of the replication clamp loaders in the semi-conservative telomere replication and their relationship to telomerase- and recombination mechanisms of telomere addition remains ambiguous. We have investigated the variant clamp loader Ctf18 RFC (Replication Factor C). To understand the role of Ctf18 at the telomere, we first investigated genetic interactions after loss of Ctf18 and TLC1 (the yeast telomerase RNA).

Allosteric drug discrimination is coupled to mechanochemical changes in the kinesin-5 motor core.

Essential in mitosis, the human Kinesin-5 protein is a target for >80 classes of allosteric compounds that bind to a surface-exposed site formed by the L5 loop. Not established is why there are differing efficacies in drug inhibition. Here we compare the ligand-bound states of two L5-directed inhibitors against 15 Kinesin-5 mutants by ATPase assays and IR spectroscopy.

ATP hydrolysis in Eg5 kinesin involves a catalytic two-water mechanism.

Motor proteins couple steps in ATP binding and hydrolysis to conformational switching both in and remote from the active site. In our kinesin.AMPPPNP crystal structure, closure of the active site results in structural transformations appropriate for microtubule binding and organizes an orthosteric two-water cluster.

Crystal structure of the GTPase-activating protein-related domain from IQGAP1.

IQGAP1 is a 190-kDa molecular scaffold containing several domains required for interaction with numerous proteins. One domain is homologous to Ras GTPase-activating protein (GAP) domains. However, instead of accelerating hydrolysis of bound GTP on Ras IQGAP1, using its GAP-related domain (GRD) binds to Cdc42 and Rac1 and stabilizes their GTP-bound states.