We previously performed targeted sequencing of autism risk genes in probands from the Autism Clinical and Genetic Resources in China (ACGC) (phase I). Here, we expand this analysis to a larger cohort of patients (ACGC phase II) to better understand the prevalence, inheritance, and genotype–phenotype correlations of likely gene-disrupting (LGD) mutations for autism candidate genes originally identified in cohorts of European descent. We sequenced 187 autism candidate genes in an additional 784 probands and 85 genes in 599 probands using single-molecule molecular inversion probes. We tested the inheritance of potentially pathogenic mutations, performed a meta-analysis of phase I and phase II data and combined our results with existing exome sequence data to investigate the phenotypes of carrier parents and patients with multiple hits in different autism risk genes. We validated recurrent, LGD, de novo mutations (DNMs) in 13 genes. We identified a potential novel risk gene (ZNF292), one novel gene with recurrent LGD DNMs (RALGAPB), as well as genes associated with macrocephaly (GIGYF2 and WDFY3). We identified the transmission of private LGD mutations in genes predominantly associated with DNMs and showed that parental carriers tended to share milder autism-related phenotypes. Patients that carried DNMs in two or more candidate genes show more severe phenotypes. We identify new risk genes and transmission of deleterious mutations in genes primarily associated with DNMs. The fact that parental carriers show milder phenotypes and patients with multiple hits are more severe supports a multifactorial model of risk.
1 February 2020 in Oxidative Medicine and Cellular Longevity
The ubiquitin-proteasome pathway and autophagy-lysosome pathway are two major routes for clearance of aberrant cellular components to maintain protein homeostasis and normal cellular functions. Accumulating evidence shows that these two pathways are impaired during cerebral ischemia, which contributes to ischemic-induced neuronal necrosis and apoptosis. This review aims to critically discuss current knowledge and controversies on these two pathways in response to cerebral ischemic stress. We also discuss molecular mechanisms underlying the impairments of these protein degradation pathways and how such impairments lead to neuronal damage after cerebral ischemia. Further, we review the recent advance on the understanding of the involvement of these two pathways in the pathological process during many therapeutic approaches against cerebral ischemia. Despite recent advances, the exact role and molecular mechanisms of these two pathways following cerebral ischemia are complex and not completely understood, of which better understanding will provide avenues to develop novel therapeutic strategies for ischemic stroke.
Stress granules (SGs) are cytoplasmic assemblies in response to a variety of stressors. We report a new neurodevelopmental disorder (NDD) with common features of language problems, intellectual disability, and behavioral issues caused by de novo likely gene-disruptive variants in UBAP2L , which encodes an essential regulator of SG assembly. Ubap2l haploinsufficiency in mouse led to social and cognitive impairments accompanied by disrupted neurogenesis and reduced SG formation during early brain development. On the basis of data from 40,853 individuals with NDDs, we report a nominally significant excess of de novo variants within 29 genes that are not implicated in NDDs, including 3 essential genes ( G3BP1 , G3BP2 , and UBAP2L ) in the core SG interaction network. We validated that NDD-related de novo variants in newly implicated and known NDD genes, such as CAPRIN1 , disrupt the interaction of the core SG network and interfere with SG formation. Together, our findings suggest the common SG pathology in NDDs.
Background Autophagy is a highly conserved mechanism for degradation and recycling of long-lived proteins and damaged organelle to maintain cell homeostasis. Deregulation of autophagy has been associated with tumorigenesis. Beclin 1 is an essential autophagy protein and its upregulation has been observed in most colorectal cancer tissues. However, there is a small population of colorectal cancers with downregulation of Beclin 1. Aim The purpose of this study was to investigate the role autophagy plays in colorectal cancers with downregulaion of Beclin 1. Methods LC3 protein, an autophagosome marker, was assessed by ICH and WB in colorectal cancers tissues. An anti-tumor effect of Beclin 1 was examined by introducing exogenous Beclin 1 in vitro. Colony formation assay, growth curves and mouse xenograft were analysed. Results Our results showed that LC3 was suppressed in the colorectal cancers (9.86 %) with downregulation of Beclin 1. Moreover, overexpression of Beclin 1 inhibited colorectal cancer cell growth and enhanced the rapamycin-induced antitumor effect in vitro. Conclusion Downregulation of Beclin 1 and autophagy inhibition play an important role in a part of colorectal cancers. Activating autophagy or overexperssion of Beclin 1 may be an effective treatment for some colorectal cancers. Detection of expression profile of Beclin 1 in colorectal cancers could be a strategy for new diagnostic and therapeutic methods.
Traditional Chinese medicine (TCM) represents the crystallization of Chinese wisdom and civilization. It has been valued as the renewable source for the discovery of novel drugs, owing to its long-term proved efficacy in human diseases and abundant biologically active components pools. To dissect the mystery of TCM, modern technologies such as omics approaches (proteomics, genomics, metabolomics) and drug screening technologies (high through-put screening, high content screening and virtual screening) have been widely applied to either identify the drug target of TCM or identify the active component with certain bio-activity. The advent of high content screening technology has absolutely contributed to a breakthrough in compounds discovery and influenced the evolution of technology in screening field. The review introduces the concept and principle of high content screening, lists and compares the currently used HCS instruments, and summarizes the examples from ours and others research work which applied HCS in TCM-derived compounds screening. Meanwhile, this article also discusses the advantages and limitations of HSC technology in drug discovery from TCM libraries.