Identification of a New Genomic Hot Spot of Evolutionary Diversification of Protein Function

Winkelmann, Aline; You, Xintian; Grünewald, Nora; Häussler, Ute; Krestel, Heinz; Haas, Carola A.; Schwarz, Günter; Chen, Wei; Meier, Jochen C.

doi:10.1371/journal.pone.0125413

Cited by 6 publications

(7 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A ), including the mouse‐specific alternative GlyR β splice variant of unknown function recently described in mouse SC (Winkelmann et al . ). These results open the possibility for expression of splice‐specific GlyR function in the mouse nAc, as recently described for GlyR α1ins and GlyR α3K (Eichler et al .…”

Section: Discussionmentioning

confidence: 97%

Presence of ethanol‐sensitive glycine receptors in medium spiny neurons in the mouse nucleus accumbens

Förstera

Muñoz

Lobo

et al. 2017

The Journal of Physiology

View full text Add to dashboard Cite

Alcohol abuse causes major social, economic and health-related problems worldwide. Alcohol, like other drugs of abuse, increases levels of dopamine in the nucleus accumbens (nAc), facilitating behavioural reinforcement and substance abuse. Previous studies suggested that glycine receptors (GlyRs) are involved in the regulation of accumbal dopamine levels. Here, we investigated the presence of GlyRs in accumbal dopamine receptor medium spiny neurons (MSNs) of C57BL/6J mice, analysing mRNA expression levels and immunoreactivity of GlyR subunits, as well as ethanol sensitivity. We found that GlyR α1 subunits are expressed at higher levels than α2, α3 and β in the mouse nAc and were located preferentially in dopamine receptor 1 (DRD1)-positive MSNs. Interestingly, the glycine-evoked currents in dissociated DRD1-positive MSNs were potentiated by ethanol. Also, the potentiation of the GlyR-mediated tonic current by ethanol suggests that they modulate the excitability of DRD1-positive MSNs in nAc. This study should contribute to understanding the role of GlyR α1 in the reward system and might help to develop novel pharmacological therapies to treat alcoholism and other addiction-related and compulsive behaviours.

show abstract

Section: Discussionmentioning

confidence: 97%

Presence of ethanol‐sensitive glycine receptors in medium spiny neurons in the mouse nucleus accumbens

Förstera

Muñoz

Lobo

et al. 2017

The Journal of Physiology

View full text Add to dashboard Cite

show abstract

“…The cells were then washed twice with PBS and fixed with 3.7% paraformaldehyde for 10 min at room temperature. Primary rat hippocampal neurons were a gift of J. Meier, MDC Berlin, and prepared and cultured as previously described (42).…”

Section: Methodsmentioning

confidence: 99%

Amyloid-β(1–42) Aggregation Initiates Its Cellular Uptake and Cytotoxicity

Jin

Kedia

Illes‐Toth

et al. 2016

Journal of Biological Chemistry

102

116

View full text Add to dashboard Cite

The accumulation of amyloid ␤ peptide(1-42) (A␤(1-42)) in extracellular plaques is one of the pathological hallmarks of Alzheimer disease (AD). Several studies have suggested that cellular reuptake of A␤(1-42) may be a crucial step in its cytotoxicity, but the uptake mechanism is not yet understood. A␤ may be present in an aggregated form prior to cellular uptake. Alternatively, monomeric peptide may enter the endocytic pathway and conditions in the endocytic compartments may induce the aggregation process. Our study aims to answer the question whether aggregate formation is a prerequisite or a consequence of A␤ endocytosis. We visualized aggregate formation of fluorescently labeled A␤(1-42) and tracked its internalization by human neuroblastoma cells and neurons. ␤-Sheet-rich A␤(1-42) aggregates entered the cells at low nanomolar concentration of A␤(1-42). In contrast, monomer uptake faced a concentration threshold and occurred only at concentrations and time scales that allowed A␤(1-42) aggregates to form. By uncoupling membrane binding from internalization, we found that A␤(1-42) monomers bound rapidly to the plasma membrane and formed aggregates there. These structures were subsequently taken up and accumulated in endocytic vesicles. This process correlated with metabolic inhibition. Our data therefore imply that the formation of ␤-sheet-rich aggregates is a prerequisite for A␤(1-42) uptake and cytotoxicity.One of the pathological hallmarks of Alzheimer disease (AD) 2 is the presence of extracellular plaques composed mainly of 42-amino acid amyloid ␤ peptide (A␤(1-42)) (1). The small hydrophobic A␤(1-42) peptide, which is generated by proteolytic cleavage of the amyloid precursor protein, is released as a monomer from the plasma membrane into extracellular space, and tends to aggregate spontaneously into oligomeric, protofibrillar, and fibrillar assemblies (2-4). Oligomeric species of A␤(1-42) are tightly linked to AD pathogenesis and are presumed to be the cause of neuronal damage (5). Several studies have suggested that the reuptake of extracellular A␤(1-42) into neurons may lead to the formation of intracellular aggregates, resulting in neuronal damage and neurotoxicity (6 -8). Endocytosis of misfolded proteins has also been observed in cell models of the tau protein, ␣-synuclein and huntingtin (9, 10), and recent evidence suggests that it may be the initial step in the replication of the misfolded protein structures by prion mechanisms (10 -14). Several possible endocytic pathways, such as macropinocytosis and receptor-mediated endocytosis, have been discussed for A␤ and other misfolded protein aggregates (15-19). However, our understanding of the connection between aggregation and cytotoxicity is still limited. It has not been conclusively determined how and when the A␤(1-42) peptide becomes toxic, whether A␤ aggregates prior to internalization or during the internalization process and, if so, in which intracellular compartments the aggregates form. Elucidating the connection between aggregation and i...

show abstract

“…Each chimeric hotspot is made up of a pair of reverse complementary sequences in the same DNA strand. The hotspots here are potential templates of chimeras which are generated in MDA procedure, and are different from the other types of hotspots in the genome, such as recombination hotspots [15] and functional hotspots [16]. In the human genome, there are numerous chimeric hotspots, especially hotspots with short overlaps.…”

Section: Introductionmentioning

confidence: 99%

Hotspot Selective Preference of the Chimeric Sequences Formed in Multiple Displacement Amplification

Lü

Duan

et al. 2017

IJMS

View full text Add to dashboard Cite

Multiple displacement amplification (MDA) is considered to be a conventional approach to comprehensive amplification from low input DNA. The chimeric reads generated in MDA lead to severe disruption in some studies, including those focusing on heterogeneity, structural variation, and genetic recombination. Meanwhile, the generation of by-products gives a new approach to gain insights into the reaction process of φ29 polymerase. Here, we analyzed 36.7 million chimeras and screened 196 billion chimeric hotspots in the human genome, as well as evaluating the hotspot selective preference of chimeras. No significant preference was captured in the distributions of chimeras and hotspots among chromosomes. Hotspots with overlaps for 12–13 nucleotides (nt) were most likely to be selected as templates in chimera generation. Meanwhile, a regularly selective preference was noticed in overlap GC content. The preferences in overlap length and GC content was shown to be pertinent to the sequence denaturation temperature, which pointed out the optimization direction for reducing chimeras. Distance preference between two segments of chimeras was 80–280 nt. The analysis is beneficial for reducing the chimeras in MDA, and the characterization of MDA chimeras is helpful in distinguishing MDA chimeras from chimeric sequences caused by disease.

show abstract

Identification of a New Genomic Hot Spot of Evolutionary Diversification of Protein Function

Cited by 6 publications

References 38 publications

Presence of ethanol‐sensitive glycine receptors in medium spiny neurons in the mouse nucleus accumbens

Presence of ethanol‐sensitive glycine receptors in medium spiny neurons in the mouse nucleus accumbens

Amyloid-β(1–42) Aggregation Initiates Its Cellular Uptake and Cytotoxicity

Hotspot Selective Preference of the Chimeric Sequences Formed in Multiple Displacement Amplification

Contact Info

Product

Resources

About