レセプター・トランスミッター相互作用のストキャスティック特性による内在の量子的変動性
D S Faber1, W S Young, P Legendre
1Neurobiology Laboratory, State University of New York, Buffalo 14214.
まとめ
シナプス伝播は必ずしも均一ではない. 受容体の飽和度ではなく,ストカスティックチャネルの行動が,シナプス量子変動性を説明し,シナプス可塑性のモデルに影響を与えます.
科学分野:
- 神経科学は神経科学である.
- シナプス伝送はシナプス伝送である.
- 分子シグナル伝達です.
背景:
- シナプスイベントは定量化され,単一の膀から送信器の放出を反映します.
- 中央シナプスは受容体飽和による不変量子を持つと考えられていた.
- この不変性概念は,ポストシナプスチャネル行動における固有のストキャスティシティを無視した.
研究 の 目的:
- シナプスの量子的変動に寄与する要因を調査する.
- ポストシナプス受容体の飽和が量子的なサイズを制限するかどうかを判断する.
- 中枢シナプスにおける量子放出モデルの適用性を評価する.
主な方法:
- 分散と確率的受容体相互作用を含む量子的な放出をモデル化するためにモンテカルロシミュレーションを使用した.
- 胚性および成人マウトナー細胞における抑制シナプスイベントを分析した.
- 少数の可用ポストシナプスチャネルと多数の可用ポストシナプスチャネルを比較したシナプス反応.
主要な成果:
- シミュレーションにより,飽和ではなく,ストカスティックチャネルの行動が,シナプス応答の振幅と運動学の内在的な変動を引き起こすことが明らかになった.
- シナプス反応は,数少ないポストシナプスチャネルが利用可能な場合に,有意な変動を示した.
- マウトナー細胞からの実験データは,チャネル数と応答変数に関するシミュレーションの発見を確認した.
結論:
- 中枢シナプスの量子サイズは不変ではなく,ポストシナプス受容体のストキャスティックな性質の影響を受けます.
- 量子放出モデルの適用性は維持され,シナプス改変部位の局所化を可能にします.
- 発見は抑制性シナプスと刺激性シナプスの両方に関連しており,受容体飽和性仮説に異議を唱える.
関連する概念動画
Mismatch Repair
Overview
Mutation, Gene Flow, and Genetic Drift
In a population that is not at Hardy-Weinberg equilibrium, the frequency of alleles changes over time. Therefore, any deviations from the five conditions of Hardy-Weinberg equilibrium can alter the genetic variation of a given population. Conditions that change the genetic variability of a population include mutations, natural selection, non-random mating, gene flow, and genetic drift (small population size).Mechanisms of Genetic VariationThe original sources of genetic variation are mutations,...
Mismatch Repair
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
Propagation of Uncertainty from Systematic Error
The atomic mass of an element varies due to the relative ratio of its isotopes. A sample's relative proportion of oxygen isotopes influences its average atomic mass. For instance, if we were to measure the atomic mass of oxygen from a sample, the mass would be a weighted average of the isotopic masses of oxygen in that sample. Since a single sample is not likely to perfectly reflect the true atomic mass of oxygen for all the molecules of oxygen on Earth, the mass we obtain from this particular...
Genetic Variation
Genetic variation is the diversity in DNA sequences found among individuals of the same species. This diversity is crucial for a species' survival because it helps organisms adapt to environmental changes. Genetic variation begins with fertilization, where an egg and sperm cell merge. Each of these cells carries 23 chromosomes, up to 46 in the fertilized egg. Chromosomes are long DNA strands that contain genes, the basic units of heredity.
Genes exist in different versions called alleles, which...
Genes exist in different versions called alleles, which...
Spontaneous and Induced Mutations
Spontaneous mutations arise infrequently during DNA replication due to errors in the process. A key factor behind these errors is tautomeric shifts in nitrogenous bases, where bases transition from keto to enol forms or amino to imino forms. This shift can alter base-pairing rules, leading to mutations. Additionally, reactive oxygen species (ROS) arising from aerobic metabolism can damage DNA, resulting in depurination (loss of a purine base) or depyrimidination (loss of a pyrimidine base).


