A distinct neurodevelopmental syndrome with intellectual disability, autism spectrum disorder, characteristic facies, and macrocephaly is caused by defects in CHD8.

A decade ago, we described novel de novo submicroscopic deletions of chromosome 14q11.2 in three children with developmental delay, cognitive impairment, and similar dysmorphic features, including widely-spaced eyes, short nose with flat nasal bridge, long philtrum, prominent Cupid's bow of the upper lip, full lower lip, and auricular anomalies. We suggested that this constituted a new multiple congenital anomaly-intellectual disability syndrome due to defects in CHD8 and/or SUPT16H. The three patients in our original cohort were between 2 years and 3 years of age at the time. Here we present a fourth patient and clinical updates on our previous patients. To document the longitudinal course more fully, we integrate published reports of other patients and describe genotype-phenotype correlations among them. Children with the disorder present with developmental delay, intellectual disability, and/or autism spectrum disorder in addition to characteristic facies. Gastrointestinal and sleep problems are notable. The identification of multiple patients with the same genetic defect and characteristic clinical phenotype, confirms our suggestion that this is a syndromic disorder caused by haploinsufficiency or heterozygous loss of function of CHD8.

Signaling pathways coordinating the alkaline pH response confer resistance to the hevein-type plant antimicrobial peptide Pn-AMP1 in Saccharomyces cerevisiae.

MAIN CONCLUSION: Genome-wide screening of Saccharomyces cerevisiae revealed that signaling pathways related to the alkaline pH stress contribute to resistance to plant antimicrobial peptide, Pn-AMP1. Plant antimicrobial peptides (AMPs) are considered to be promising candidates for controlling phytopathogens. Pn-AMP1 is a hevein-type plant AMP that shows potent and broad-spectrum antifungal activity. Genome-wide chemogenomic screening was performed using heterozygous and homozygous diploid deletion pools of Saccharomyces cerevisiae as a chemogenetic model system to identify genes whose deletion conferred enhanced sensitivity to Pn-AMP1. This assay identified 44 deletion strains with fitness defects in the presence of Pn-AMP1. Strong fitness defects were observed in strains with deletions of genes encoding components of several pathways and complex known to participate in the adaptive response to alkaline pH stress, including the cell wall integrity (CWI), calcineurin/Crz1, Rim101, SNF1 pathways and endosomal sorting complex required for transport (ESCRT complex). Gene ontology (GO) enrichment analysis of these genes revealed that the most highly overrepresented GO term was "cellular response to alkaline pH". We found that 32 of the 44 deletion strains tested (72 %) showed significant growth defects compared with their wild type at alkaline pH. Furthermore, 9 deletion strains (20 %) exhibited enhanced sensitivity to Pn-AMP1 at ambient pH compared to acidic pH. Although several hundred plant AMPs have been reported, their modes of action remain largely uncharacterized. This study demonstrates that the signaling pathways that coordinate the adaptive response to alkaline pH also confer resistance to a hevein-type plant AMP in S. cerevisiae. Our findings have broad implications for the design of novel and potent antifungal agents.

Lichen-forming fungus Caloplaca flavoruscens inhibits transcription factors and chromatin remodeling system in fungi.

Lichen-forming fungi and extracts derived from them have been used as alternative medicine sources for millennia and recently there has been a renewed interest in their known bioactive properties for anticancer agents, cosmetics and antibiotics. Although lichen-forming fungus-derived compounds are biologically and commercially valuable, few studies have been performed to determine their modes of action. This study used chemical-genetic and chemogenomic high-throughput analyses to gain insight into the modes of action of Caloplaca flavoruscens extracts. High-throughput screening of 575 lichen extracts was performed and 39 extracts were identified which inhibited yeast growth. A C. flavoruscens extract was selected as a promising antifungal and was subjected to genome-wide haploinsufficiency profiling and homozygous profiling assays. These screens revealed that yeast deletion strains lacking Rsc8, Pro1 and Toa2 were sensitive to three concentrations (IC25.5, IC25 and IC50, respectively) of C. flavoruscens extract. Gene-enrichment analysis of the data showed that C. flavoruscens extracts appear to perturb transcription and chromatin remodeling.