Functional characterization of Wiskott-Aldrich syndrome protein and scar homolog (WASH), a bi-modular nucleation-promoting factor able to interact with biogenesis of lysosome-related organelle subunit 2 (BLOS2) and gamma-tubulin.

The Arp2/3 complex is essential for actin filament nucleation in a variety of cellular processes. The activation of the Arp2/3 complex is mediated by nucleation-promoting factors, such as the Wiskott-Aldrich syndrome family proteins, which share a WCA (WH2 domain, central region, acidic region) catalytic module at the C-terminal region, required for Arp2/3 activation, but diverge at the N-terminal region, required for binding to specific activators. Here, we report the characterization of WASH, a new member of the WAS family that has nucleation-promoting factor activity and recently has been demonstrated to play a role in endosomal sorting.

Microdeletion/duplication at the Xq28 IP locus causes a de novo IKBKG/NEMO/IKKgamma exon4_10 deletion in families with Incontinentia Pigmenti.

The Incontinentia Pigmenti (IP) locus contains the IKBKG/NEMO/IKKgamma gene and its truncated pseudogene copy, IKBKGP/deltaNEMO. The major genetic defect in IP is a heterozygous exon4_10 IKBKG deletion (IKBKGdel) caused by a recombination between two consecutive MER67B repeats. We analyzed 91 IP females carrying the IKBKGdel, 59 of whom carrying de novo mutations (65%).

DDX11L: a novel transcript family emerging from human subtelomeric regions.

Background: The subtelomeric regions of human chromosomes exhibit an extraordinary plasticity. To date, due to the high GC content and to the presence of telomeric repeats, the subtelomeric sequences are underrepresented in the genomic libraries and consequently their sequences are incomplete in the finished human genome sequence, and still much remains to be learned about subtelomere organization, evolution and function. Indeed, only in recent years, several studies have disclosed, within human subtelomeres, novel gene family members.

Alterations of the IKBKG locus and diseases: an update and a report of 13 novel mutations.

Mutations in the inhibitor of kappa light polypeptide gene enhancer in B-cells, kinase gamma (IKBKG), also called nuclear factor-kappaB (NF-kB) essential modulator (NEMO), gene are the most common single cause of incontinentia pigmenti (IP) in females and anhydrotic ectodermal dysplasia with immunodeficiency (EDA-ID) in males. The IKBKG gene, located in the Xq28 chromosomal region, encodes for the regulatory subunit of the inhibitor of kappaB (IkB) kinase (IKK) complex required for the activation of the NF-kB pathway. Therefore, the remarkably heterogeneous and often severe clinical presentation reported in IP is due to the pleiotropic role of this signaling transcription pathway.

Phaseless imaging with experimental data: facts and challenges.

Two-dimensional target characterization using inverse profiling approaches with total-field phaseless data is discussed. Two different inversion schemes are compared. In the first one, the intensity-only data are exploited in a minimization scheme, thanks to a proper definition of the cost functional.

MRX87 family with Aristaless X dup24bp mutation and implication for polyAlanine expansions.

Background: Cognitive impairments are heterogeneous conditions, and it is estimated that 10% may be caused by a defect of mental function genes on the X chromosome. One of those genes is Aristaless related homeobox (ARX) encoding a polyA-rich homeobox transcription factor essential for cerebral patterning and its mutations cause different neurologic disorders. We reported on the clinical and genetic analysis of an Italian family with X-linked mental retardation (XLMR) and intra-familial heterogeneity, and provided insight into its molecular defect.

Ovarian dysfunction and FMR1 alleles in a large Italian family with POF and FRAXA disorders: case report.

Background: The association between premature ovarian failure (POF) and the FMR1 repeat number (41> CGGn< 200) has been widely investigated. Current findings suggest that the risk estimation for POF can be calculated in the offspring of women with pre-mutated FMR1 alleles.

Case Presentation: We describe the coexistence in a large Italian kindred of Fragile X syndrome and familial POF in females with ovarian dysfunctions who carried normal or expanded FMR1 alleles.

Functional characterization of the TMLH gene: promoter analysis, in situ hybridization, identification and mapping of alternative splicing variants.

Carnitine is a molecule with well-documented pleiotropic functions whose biosynthesis involves four catalytic steps. Here, we report a detailed analysis of the expression and transcriptional control of TMLH gene, which codifies for the first enzyme of carnitine biosynthesis. TMLH maps at the extreme end of Xq28, a chromosomal region of high genomic instability.

Faithful non-linear imaging from only-amplitude measurements of incident and total fields.

Applicability of inverse scattering based imaging procedures can be broadened by developing new approaches exploiting only amplitude data. As a matter of fact, this can open the way to simpler and less expensive measurement set-ups. In this respect, a two-step based procedure for solving electromagnetic nonlinear inverse scattering problems from only amplitude measurements of the total field has been recently proposed [1,2].

Clinical diagnosis of incontinentia pigmenti in a cohort of male patients.

Eighteen male patients with incontinentia pigmenti (IP) showed the characteristic clinical features and, when examined, histologic skin defects observed in female patients with IP. Six of the patients had neurologic, ophthalmologic, or dental manifestations as well. Three patients showed evidence by polymerase chain reaction analysis of both the normal NEMO gene and the exon 4-10 deletion in NEMO that occurs in the majority of affected girls with IP, confirming postzygotic mosaicism for the NEMO gene.

Inverse scattering from phaseless measurements of the total field on open lines.

A new solution approach to inverse scattering from aspect-limited phaseless measurements of the total field is introduced and discussed. In analogy with the case of measurements on closed curves [J. Opt.

Heterozygosity mapping by quantitative fluorescent PCR reveals an interstitial deletion in Xq26.2-q28 associated with ovarian dysfunction.

Background: Deletions of Xq chromosome are reported for a number of familial conditions exhibiting premature ovarian failure (POF) and early menopause (EM).

Methods And Results: We describe the inheritance of an interstitial deletion of the long arm of the X chromosome associated with either POF or EM in the same family. Cytogenetic studies and heterozygosity mapping by quantitative fluorescent PCR revealed a 46,X,del(X)(q26.

The DNA sequence of the human X chromosome.

The human X chromosome has a unique biology that was shaped by its evolution as the sex chromosome shared by males and females. We have determined 99.3% of the euchromatic sequence of the X chromosome.

Functional analysis of TMLH variants and definition of domains required for catalytic activity and mitochondrial targeting.

epsilon-N-Trimethyllysine hydroxylase (TMLH) (EC 1.14.11.

Molecular analysis of the genetic defect in a large cohort of IP patients and identification of novel NEMO mutations interfering with NF-kappaB activation.

Incontinentia Pigmenti (IP) is an X-linked genodermatosis that is lethal for males and present in females with abnormal skin pigmentation and high variable clinical signs, including retinal detachment, anodontia, alopecia, nail dystrophy and nervous system defects. The NF-kappaB essential modulator (NEMO) gene, responsible for IP, encodes the regulatory subunit of the IkappaB kinase (IKK) complex required for nuclear factor kappaB (NF-kappaB) activation. We analyzed the NEMO gene in 122 IP patients and identified mutations in 83 (36 familiar and 47 sporadic cases).

VAMP subfamilies identified by specific R-SNARE motifs.

In eukaryotes, interactions among the alpha-helical coiled-coil domains (CCDs) of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) play a pivotal role in mediating the fusion among vesicles and target membranes. Surface residues of such CCDs are major candidates to regulate the specificity of membrane fusion, as they may alter local charge at the interaction layers and surface of the fusion complex, possibly modulating its formation and/or the binding of non-SNARE regulatory factors. Based on alternate patterns in surface residues, we have identified two motifs which group vesicular SNAREs in two novel subfamilies: RG-SNAREs and RD-SNAREs.

Inverse scattering from phaseless measurements of the total field on a closed curve.

A new approach for quantitative electromagnetic imaging of scatterers located in free space from phaseless data is proposed and discussed. The procedure splits the problem into two steps. In the first one, we solve a phase-retrieval problem for the total field, thus estimating the amplitude and phase of the scattered field.

Characterization of the human STAT5A and STAT5B promoters: evidence of a positive and negative mechanism of transcriptional regulation.

We recently published the genomic characterization of the STAT5A and STAT5B paralogous genes that are located head to head in the 17q21 chromosome and share large regions of sequence identity. We here demonstrate by transient in vitro transfection that STAT5A and STAT5B promoters are able to direct comparable levels of transcription. The expression of basal promoters is enhanced after Sp1 up-regulation in HeLa and SL2 cells while DNA methylation associated to the recruitment of MeCP2 methyl CpG binding protein down-regulates STAT5A and B promoters by interfering with Sp1-induced transcription.

Transcriptome analysis of mouse stem cells and early embryos.

Understanding and harnessing cellular potency are fundamental in biology and are also critical to the future therapeutic use of stem cells. Transcriptome analysis of these pluripotent cells is a first step towards such goals. Starting with sources that include oocytes, blastocysts, and embryonic and adult stem cells, we obtained 249,200 high-quality EST sequences and clustered them with public sequences to produce an index of approximately 30,000 total mouse genes that includes 977 previously unidentified genes.

Human synaptobrevin-like 1 gene basal transcription is regulated through the interaction of selenocysteine tRNA gene transcription activating factor-zinc finger 143 factors with evolutionary conserved cis-elements.

The synaptobrevin-like 1 (SYBL1) gene is ubiquitously expressed and codes for an unusual member of the v-SNAREs molecules implicated in cellular exocytosis. This X-linked gene has the peculiarity of also being present on the Y chromosome in a transcriptional inactive status. Moreover, although ubiquitous, the function of SYBL1 is prominent in specific tissues, such as brain.

Otosclerosis: exclusion of linkage to the OTSC1 and OTSC2 loci in four Italian families.

Otosclerosis is the single most common cause of hearing impairment among adult caucasians. Little is known about its aetiology and its molecular aspects. Until now, genetic linkage in otosclerosis has been demonstrated in an Indian family and a Belgian family, showing the presence of two otosclerosis loci, OTSC1 and OTSC2, respectively.

High-resolution methylation analysis of the hMLH1 promoter in sporadic endometrial and colorectal carcinomas.

Background: Microsatellite instability (MSI) has been reported in endometrial carcinoma (EC) and in colorectal carcinoma (CRC), primarily as a result of defective DNA mismatch repair (MMR). The MMR gene hMLH1 commonly is inactivated in both EC and CRC. In the current study, epigenetic mechanisms involved in hMLH1 inactivation have been investigated to further elucidate the role of these mechanisms in the pathogenesis of EC and CRC.

Folate treatment and unbalanced methylation and changes of allelic expression induced by hyperhomocysteinaemia in patients with uraemia.

Background: Hyperhomocysteinaemia occurs in several genetically determined and acquired disorders and is highly prevalent in patients with uraemia. In these disorders, homocysteine precursor S-adenosylhomocysteine, a powerful competitive inhibitor of S-adenosylmethionine-dependent methyltransferases, is increased, suggesting unbalanced methylation. We aimed to investigate whether DNA hypomethylation is present in patients with uraemia who also have hyperhomocysteinaemia and whether regulation of specific classes of genes, dependent on DNA methylation, is compromised.