The abnormal expansion of unstable simple sequence DNA repeats can cause human disease through a variety of mechanisms, including gene loss-of-function, toxic gain-of-function of the encoded protein and toxicity of the repeat-containing RNA transcript. Disease-associated unstable DNA repeats display unusual biophysical properties, including the ability to adopt non-B-DNA structures. CAG•CTG tri...

background: expansion of gaa trinucleotide repeats is the molecular basis of friedreich’s ataxia (frda). precise detection of the gaa expansion repeat in frataxin gene has always been a challenge. different molecular methods have been suggested for detection of gaa expansion, including; short-pcr, long-pcr, triplet repeat primed-pcr (tp-pcr) and southern blotting. the aim of study was to evalua...

OBJECTIVE Report the invention and structural analysis of the new model of anterior spinal instrumentation (KKU expandable cage) that is expandable for space filling after vertebral body resection while simultaneously stabilize the upper vertebra with the lower vertebra, to tolerate the thoracolumbar physiologic load and augment the interbody arthrodesis of the spine. MATERIAL AND METHOD The ...

We have studied the contribution of mismatch sequences to the trinucleotide repeat expansion that causes hereditary diseases. Using an oligonucleotide duplex, (CAG)5/(CTG)5, as a template-primer, DNA synthesis was carried out using either Escherichia coli DNA polymerase I (Klenow fragment) or human immunodeficiency virus type I reverse transcriptase (HIV-RT). Both enzymes expanded the repeat se...

The hexamer repeat sequence (TTAGGG)(n), found at the ends of all vertebrate chromosomes, was previously identified as the main building element of one member of a HindIII satellite DNA family characterized in the genome of the bivalve mollusc Donax trunculus. It was also found in 22 perfect tandem repeats in a cloned junction region juxtaposed to the proper satellite sequence, from which the D...

The yeast transcriptional activator HAP1 contains a DNA-binding domain homologous to GAL4, PPR1, and related factors. By selecting random HAP1-binding sites, we found that HAP1, like GAL4, binds to two CGG triplets. Unlike GAL4, the CGGs in the HAP1 consensus are in a direct and not inverted orientation. Sites with inverted CGGs were not recovered, and mutations converting the direct repeat of ...

Sporadic microsatellite mutations are frequently observed in lung, bladder, and head and neck tumors with intact DNA mismatch repair. AAAG tetranucleotide repeats appear to be especially prone to the accumulation of these mutations. We hypothesized that occurrences of microsatellite mutations in these cancers may be linked to DNA damage caused by exposure to carcinogens in tobacco smoke. To tes...

TAL effectors, from the plant-pathogenic bacterial genus Xanthomonas, are DNA binding proteins that can be engineered to bind to almost any sequence of interest. The DNA target of the TAL effector is encoded by a modular central repeat region, with each repeat specifying a single binding site nucleotide. TAL effectors can be targeted to novel DNA sequences by assembling the corresponding repeat...

The mouse c-Ki-ras protooncogene promoter contains a homopurine-homopyrimidine domain that exhibits S1 nuclease sensitivity in vitro. We have studied the structure of this DNA region in a supercoiled state using a number of chemical probes for non-B DNA conformations including diethyl pyrocarbonate, osmium tetroxide, chloroacetaldehyde, and dimethyl sulfate. The results demonstrate that two typ...