Search results for "MUTATION"
showing 10 items of 2830 documents
Laser Pressure Catapulting (LPC): Optimization LPC-System and Genotyping of Colorectal Carcinomas
2005
Genotype analysis is becoming more and more useful in clinical practice, since specific mutations in tumors often correlate with prognosis and/or therapeutic response. Unfortunately, current molecular analytical techniques often require time-consuming and costly steps of analysis, thus making their routine clinical use difficult. Moreover, one of the most difficult problems arising during tumor research is that of their cell heterogeneity, which depends on their clear molecular heterogeneity. SSCP analysis discriminates by means of aberrant electrophoresis migration bands, mutated alleles which may represent as little as 15-20% of their total number. Nevertheless, in order to identify by se…
Mutational analysis of eggplant latent viroid RNA processing in Chlamydomonas reinhardtii chloroplast.
2009
Viroids of the family Avsunviroidae, such as eggplant latent viroid (ELVd), contain hammerhead ribozymes and replicate in the chloroplasts of the host plant through an RNA-based symmetrical rolling-circle mechanism in which oligomeric RNAs of both polarity are processed to monomeric linear RNAs (by cleavage) and to monomeric circular RNAs (by ligation). Using an experimental system consisting of transplastomic lines of the alga Chlamydomonas reinhardtii, a mutational analysis of sequence and structural elements in the ELVd molecule that are involved in transcript processing in vivo in a chloroplastic context was carried out. A collection of six insertion and three deletion ELVd mutants was …
Sequence characterization of the melanocortin 1 receptor (MC1R) gene in sheep with different coat colour and identification of the putative e allele …
2010
Abstract Sequence of the melanocortin 1 receptor (MC1R) gene (the Extension locus) was obtained from a panel of 73 animals belonging to 9 Italian sheep breeds or populations (Appenninica, Bergamasca, Comisana, Cornigliese-like, Delle Langhe, Massese, Merinizzata Italiana, Sarda and Valle del Belice) with different coat colours. Evaluation of the identified polymorphisms on this phenotype was reported with in silico predictions and comparative approaches within and across breeds and across species. Five novel single nucleotide polymorphisms (SNPs), organized in three haplotypes, were detected. Another haplotype, including the two missense mutations already described for the ED allele, was id…
Next generation sequencing of HCC from European and Asian HCC cohorts. Back to p53 and Wnt/β-catenin
2013
Hepatocellular carcinoma (HCC) is the most common pri- mary liver malignancy. Here, we performed high-resolution copy- number analysis on 125 HCC tumors and whole-exome sequencing on 24 of these tumors. We identified 135 homozygous deletions and 994 somatic mutations of genes with predicted functional conse- quences. We found new recurrent alterations in four genes (ARID1A, RPS6KA3, NFE2L2 and IRF2) not previously described in HCC. Func- tional analyses showed tumor suppressor properties for IRF2, whose inactivation, exclusively found in hepatitis B virus (HBV)-related tumors, led to impaired TP53 function. In contrast, inactivation of chromatin remodelers was frequent and predominant in al…
Complementation among developmental mutants in Aspergillus nidulans.
1973
In heterokaryons between pairs of aconidial mutants of Aspergillus nidulans one of the component strains usually shows a striking prevalance in the contribution to the conidial crop. By assuming that the prevailing strain is blocked earlier and the succumbent one later in the process of differentiation, a series of mutations can be arranged in a consistent order. Some mutant strains do not fit the scheme exactly but show a general tendency to be succumbent to “early” mutants and prevalent over the “late” ones. A criterion for arraying genes involved in differentiation according to the order of their physiological action is proposed.
Self-diploidization in Saccharomyces cerevisiae kar2 heterokaryons
1993
Zygotes isolated by micromanipulation from crosses of Saccharomyces cerevisiae strains, one of which carries a kar mutation, give rise most frequently to cytoductant colonies showing the nuclear constitution of either one of the two haploid parental strains. In crosses of kar2-1 strains to wild-type, about 10% of the cytoductants of both mating types are homozygous autodiploids. There is evidence indicating that self-diploidization occurs by fusion between sibling nuclei in the heterokaryotic zygote. Here we describe this phenomenon and propose to take advantage of it for the construction of genotypically-defined diploids able to mate, and of polyploid strains, which are useful tools in gen…
Molecular Genetic Investigations in Autosomal Dominant Polycystic Kidney Disease. Gene Mutation Detection, Linkage Analysis, and Preliminary ACE Gene…
1997
Distinctive Patterns of Intraclonal Diversification In IGHV1-2*04 Immunoglobulin Receptors of Patients with Splenic Marginal Zone Lymphoma: A of Ongo…
2011
Abstract Abstract 2638 We recently demonstrated that over 30% of cases with splenic marginal-zone lymphoma (SMZL) express distinctive immunoglobulin (IG) receptors that utilize a single polymorphic variant of the IGHV1-2 gene (IGHV1-2*04) and also exhibit restricted antigen-binding site motifs and precise targeting of somatic hypermutation (SHM). On these grounds, we proposed the existence of molecular subtypes of SMZL defined by immunogenetic analysis of the IG receptors with implications for selection by specific (super) antigenic element(s) in the development of at least a major subset of SMZL. In order to gain insight as to whether antigen involvement is relevant only prior to the malig…
Clonal Interference and the Evolution of RNA Viruses
1999
In asexual populations, beneficial mutations that occur in different lineages compete with one another. This phenomenon, known as clonal interference, ensures that those beneficial mutations that do achieve fixation are of large effect. Clonal interference also increases the time between fixations, thereby slowing the adaptation of asexual populations. The effects of clonal interference were measured in the asexual RNA virus vesicular stomatitis virus; rates and average effects of beneficial mutations were quantified.