400 research outputs found
A novel point mutation within the EDA gene causes an exon dropping in mature RNA in Holstein Friesian cattle breed affected by X-linked anhidrotic ectodermal dysplasia
<p>Abstract</p> <p>Background</p> <p>X-linked anhidrotic ectodermal dysplasia is a disorder characterized by abnormal development of tissues and organs of ectodermal origin caused by mutations in the <it>EDA </it>gene. The bovine <it>EDA </it>gene encodes the ectodysplasin A, a membrane protein expressed in keratinocytes, hair follicles and sweat glands, which is involved in the interactions between cell and cell and/or cell and matrix. Four mutations causing ectodermal dysplasia in cattle have been described so far.</p> <p>Results</p> <p>We identified a new single nucleotide polymorphism (SNP) at the 9<sup>th </sup>base of exon 8 in the <it>EDA </it>gene in two calves of Holstein Friesian cattle breed affected by ectodermal dysplasia. This SNP is located in the exonic splicing enhancer (ESEs) recognized by SRp40 protein. As a consequence, the spliceosome machinery is no longer able to recognize the sequence as exonic and causes exon skipping. The mutation determines the deletion of the entire exon (131 bp) in the RNA processing, causing a severe alteration of the protein structure and thus the disease.</p> <p>Conclusion</p> <p>We identified a mutation, never described before, that changes the regulation of alternative splicing in the <it>EDA </it>gene and causes ectodermal dysplasia in cattle. The analysis of the SNP allows the identification of carriers that can transmit the disease to the offspring. This mutation can thus be exploited for a rational and efficient selection of unequivocally healthy cows for breeding.</p
Recent Advancements in the Hole-Drilling Strain-Gage Method for Determining Residual Stresses
The hole-drilling Strain-Gage method is a widely used and cost-effective technique for the evaluation of residual stresses. The test method is standardized by ASTM E837-13a, which defines the scope, measurement range, minimum requirements of instrumentation, test procedure, and algorithms and coefficients for the computation of uniform and non-uniform stress distribution. However, the standardized test method presents some limitations regarding the scope and measurement range; moreover, some typical errors involved in the measurements are not taken into account, i.e., errors due to the hole eccentricity, the local plasticity, the intermediate thickness, and the hole-bottom chamfer, which can affect the results in some cases. Also, the standard does not provide the user with a complete guide regarding the evaluation of the uncertainty connected with this type of measurement. The paper presents a more general approach that allows the correction of some errors and overcomes and some limitations of the ASTM E837-13a test method, contributing to greater accuracy of the test results
How Do Methyl Groups Enhance the Triplet Chemiexcitation Yield of Dioxetane?
Chemiluminescence is the emission of light as a result of a nonadiabatic
chemical reaction. The present work is concerned with understanding the yield
of chemiluminescence, in particular how it dramatically increases upon
methylation of 1,2-dioxetane. Both ground-state and nonadiabatic dynamics
(including singlet excited states) of the decomposition reaction of various
methyl-substituted dioxetanes have been simulated. Methyl-substitution leads to
a significant increase in the dissociation time scale. The rotation around the
O-C-C-O dihedral angle is slowed; thus, the molecular system stays longer in
the "entropic trap" region. A simple kinetic model is proposed to explain how
this leads to a higher chemiluminescence yield. These results have important
implications for the design of efficient chemiluminescent systems in medical,
environmental, and industrial applications
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