小鼠桶狀皮質抑制產後結締組織的發育
作者:
小柯機器人發布時間:2020/12/4 16:26:44
德國馬克斯·普朗克大腦研究所Moritz Helmstaedter小組發現,小鼠桶狀皮質抑制產後結締組織的發育。該研究於2020年12月3日發表於《科學》雜誌。
研究人員量化了發育過程中的小鼠體感皮層抑制性中間神經元突觸發生的電路模式。研究人員利用3D電子顯微鏡觀察了出生後前4周(出生後5至28天)小鼠細胞體、頂突和軸突初始節段的突觸神經支配。研究發現頂端樹突神經支配發生在早期,特別是目標偏好性在產後第五天(P5)幾乎與成人水平一致。
另一方面,軸突神經細胞體可能通過突觸過量和隨後抗特異性突觸去除逐漸從P5到P9獲得特異性。枝形吊燈軸突揭示了P14的第一個靶標優先選擇,但P28幾乎形成了完整的靶標特異性,這與軸突生長和脫靶突觸去除的組合相一致。這種結締組織發育概況揭示了小鼠皮質中抑制性軸突在發育過程中如何建立大腦迴路。
研究人員表示,新皮層中大腦迴路是由遷移並能形成突觸的多種神經元發育而成。
附:英文原文
Title: Postnatal connectomic development of inhibition in mouse barrel cortex
Author: Anjali Gour, Kevin M. Boergens, Natalie Heike, Yunfeng Hua, Philip Laserstein, Kun Song, Moritz Helmstaedter
Issue&Volume: 2020/12/03
Abstract: Brain circuits in the neocortex develop from diverse types of neurons that migrate and form synapses. Here we quantify the circuit patterns of synaptogenesis for inhibitory interneurons in the developing mouse somatosensory cortex. We studied synaptic innervation of cell bodies, apical dendrites and axon initial segments using 3D electron microscopy focusing on the first four weeks postnatally (postnatal days 5 to 28). We found that innervation of apical dendrites occurs early and specifically: target preference is already almost at adult levels at the fifth postnatal day (P5). Axons innervating cell bodies, on the other hand, gradually acquire specificity from P5 to P9 likely via synaptic overabundance followed by antispecific synapse removal. Chandelier axons show first target preference by P14 but develop full target specificity almost completely by P28, consistent with a combination of axon outgrowth and off-target synapse removal. This connectomic developmental profile reveals how inhibitory axons in mouse cortex establish brain circuitry during development.
DOI: 10.1126/science.abb4534
Source: https://science.sciencemag.org/content/early/2020/12/02/science.abb4534
Science:《科學》,創刊於1880年。隸屬於美國科學促進會,最新IF:41.037