A commutable cytomegalovirus calibrator is required to improve the agreement of viral load values between laboratories.

Background: Viral load testing for cytomegalovirus (CMV) is an important diagnostic tool for the management of transplant recipients and immunocompromised individuals; however, inconsistency among laboratories in quantitative measurements of viral load limits interinstitutional comparisons. These inconsistencies stem from the lack of assays cleared by the US Food and Drug Administration, the absence of international standards, the wide variety of CMV-extraction and -detection methods, and differences in materials used for calibration. A critical component of standardization is the use of calibrators that are traceable and commutable.

Functions of site-specific histone acetylation and deacetylation.

Histone acetylation regulates many cellular processes, and specific acetylation marks, either singly or in combination, produce distinct outcomes. For example, the acetylation pattern on newly synthesized histones is important for their assembly into nucleosomes by histone chaperones. Additionally, the degree of chromatin compaction and folding may be regulated by acetylation of histone H4 at lysine 16.

Histone H2B ubiquitylation controls processive methylation but not monomethylation by Dot1 and Set1.

Methylation is a relatively stable histone modification, yet regulation of the transition between mono-, di-, and trimethylation of lysine (K) residues may control dynamic processes such as transcription and DNA repair. Identifying factors that regulate the ability of methyltransferases to perform successive rounds of methylation on the same lysine residue is important for understanding the functions of histone methylation. Previous reports have indicated that ubiquitylation of histone H2B K123 is required for methylation of lysines 4 and 79 of histone H3 by the methyltransferases Set1 and Dot1, respectively.

Reduced proportion of Purkinje cells expressing paternally derived mutant Mecp2308 allele in female mouse cerebellum is not due to a skewed primary pattern of X-chromosome inactivation.

Rett syndrome (RTT) is an X-linked disorder caused by mutations in the methyl CpG binding protein 2 (MECP2) gene. The pattern of X-chromosome inactivation (XCI) is thought to play a role in phenotypic severity. In the present study, patterns of XCI were assessed by lacZ staining of embryos and adult brains of mice heterozygous for a X-linked Hmgcr-nls-lacZ transgene on a mutant mouse model of RTT.

Balanced X chromosome inactivation patterns in the Rett syndrome brain.

In Rett syndrome (RTT), an X-linked disorder essentially limited to females, neurological development goes awry. Causing this disarray in neuronal function is a mutated form of a protein known as methyl-CpG-binding protein 2 (MeCP2). Because the MECP2 gene is subject to X chromosome inactivation (XCI) in females, a number of studies have addressed whether the percentage of cells inactivating the normal vs.

Infantile hypotonia as a presentation of Rett syndrome.

Rett syndrome (RTT) is classically defined by meeting certain clinical diagnostic criteria. It affects mostly females, and one possible pathogenic mechanism was considered to involve mitochondrial function. This was based on the finding of ultrastructural alterations in the mitochondria and decreased respiratory chain enzyme activity.

Insight into Rett syndrome: MeCP2 levels display tissue- and cell-specific differences and correlate with neuronal maturation.

Rett syndrome (RTT) is a neurodevelopmental disorder caused by mutations in the methyl-CpG-binding protein 2 (MECP2) gene. Previous data have shown that MECP2 RNA is present in all mouse and human tissues tested, but the timing of expression and regional distribution have not been explored. We investigated the spatial and temporal distribution of the MeCP2 protein during mouse and human development.