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Wang, Y.-Z.

Publications and source records attributed to Wang, Y.-Z..

3 recordsLinked to original sources

Altered protein quality control contributes to noise-induced hearing loss

Exposure to damaging levels of noise is the most common cause of hearing loss and impairs high frequency hearing in more than 15 % of adult Americans. Using mice exposed to increasing levels of noise in combination with quantitative proteomics, we tested how noise insults remodel the cochlear proteome both acutely and after a two-week recovery period. We used ABR & DPOAE recordings to define the intensity of noise exposure necessary to produce temporary or permanent threshold shifts (TTS, PTS) in young adult mice and found noise at 94 and 105 dB SPL levels for 30 minutes elicits TTS and PTS, respectively. We quantified thousands of proteins and found that noise insults cause a rapid increase rather than a decrease in the levels of many proteins involved with protein homeostasis, myelin, cytoskeletal structures, and cell junctions such as the synapse. The vast majority of proteins with increased levels immediately after noise exposure showed normal levels after two weeks of recovery. However, several proteins involved in oxidative stress and neuroprotection had significantly increased levels only after the recovery period suggesting they play in important role in regeneration. Interestingly, a small panel of mitochondrial proteins were significantly altered only in PTS conditions suggesting potential discrete protein mechanisms. Our discovery-based proteomic analysis extends the recent description of noise-induced cochlear synaptopathy and shows that noise insults drive a robust proteostasis response. These data provide a new understanding of noise sensitive proteins and may inform the development of effective preventiative strategies or therapies for NIHL.

neuroscience

A cloning-free method for CRISPR/Cas9-mediated genome editing in fission yeast

The CRISPR/Cas9 system, which relies on RNA-guided DNA cleavage to induce site-specific DNA double-strand breaks, is a powerful tool for genome editing. This system has been successfully adapted for the fission yeast Schizosaccharomyces pombe by expressing Cas9 and the single-guide RNA (sgRNA) from a plasmid. In the procedures published to date, the cloning step that introduces a specific sgRNA target sequence into the plasmid is the most tedious and time-consuming. To increase the efficiency of applying the CRISPR/Cas9 system in fission yeast, we here developed a cloning-free procedure that uses gap repair in fission yeast cells to assemble two linear DNA fragments, a gapped Cas9-encoding plasmid and a PCR-amplified sgRNA insert, into a circular plasmid. Both fragments contain only a portion of the ura4 or bsdMX marker so that only the correctly assembled plasmid can confer uracil prototrophy or blasticidin resistance. We show that this gap-repair-based and cloning-free CRISPR/Cas9 procedure permits rapid and efficient point mutation knock-in, endogenous N-terminal tagging, and genomic sequence deletion in fission yeast.

genetics

Amyloid accumulation drives proteome-wide alterations in mouse models of Alzheimers disease like pathology

Amyloid beta (A{beta}) peptides impair multiple cellular pathways in the brain and play a causative role in Alzheimers disease (AD) pathology, but how the brain proteome is remodeled during this process is unknown. To identify new protein networks associated with AD-like pathology, we performed global quantitative proteomic analysis in three mouse models at pre- and post-symptomatic ages. Our analysis revealed a robust and consistent increase in Apolipoprotein E (ApoE) levels in nearly all transgenic brain regions with increased A{beta} levels. Taken together with prior findings on ApoE driving A{beta} accumulation, this analysis points to a pathological dysregulation of the ApoE-A{beta} axis. We also found dysregulation of protein networks involved in excitatory synaptic transmission consistent with AD pathophysiology. Targeted analysis of the AMPA receptor complex revealed a specific loss of TARP{gamma}-2, a key AMPA receptor trafficking protein. Expression of TARP{gamma}-2 in vivo in hAPP transgenic mice led to a restoration of AMPA currents. This database of proteome alterations represents a unique resource for the identification of protein alterations responsible for AD.\n\nHighlightsO_LIProteomic analysis of mouse brains with AD-like pathology reveals stark remodeling\nC_LIO_LIProteomic evidence points to a dysregulation of ApoE levels associated with A{beta} clearance rather than production\nC_LIO_LICo-expression analysis found distinctly impaired synapse and mitochondria modules\nC_LIO_LIIn-depth analyses of AMPAR complex points to loss of TARP{gamma}-2, which may compromise synapses in AD\nC_LI\n\neTOC BlurbProteome-wide profiling of brain tissue from three mouse models of AD-like pathology reveals A{beta}, brain region, and age dependent alterations of protein levels. This resource provides a new global protein expression atlas for the Alzheimers disease research community.

neuroscience