当哺乳动物幼体脱离温暖的母体，来到一个陌生环境后，幼体在呼吸方面如何适应这种突然转变呢？法国科研人员日前在老鼠身上检验出一种基因，它能够帮助新生幼鼠用肺呼吸。研究人员认为，这正是哺乳动物出生后存活的关键所在。
法国国家科研中心等机构的研究人员在新一期法国《神经学杂志》上报告说，哺乳动物的胎儿都处在液体环境里并通过脐带获得氧，因此在出生前，胎儿的肺部功能基本没有。此前的研究认为，哺乳动物幼体之所以一离开母体就能适应环境，主要得益于几个神经元回路，其作用仿佛心脏起搏器，能够激活呼吸系统，这样幼体就能在出生后很快开始自主呼吸。
法国国家科研中心的专家则近一步发现，一种名为TSHZ3的蛋白质在神经元的活动中发挥了关键作用。实验显示，如果老鼠幼崽细胞内编码合成TSHZ3蛋白质的基因无法表达，那么小老鼠就会在出生几分钟后窒息而亡。
未来，法国科研人员希望深入了解TSHZ3蛋白质编码基因在呼吸系统障碍中发挥的作用，从而为睡眠窒息及相关医学难题找到解决之道。(生物谷Bioon.com)
生物谷推荐原文出处：
The Journal of Neuroscience doi:10.1523/JNEUROSCI.1765-10.2010
Teashirt 3 Regulates Development of Neurons Involved in Both Respiratory Rhythm and Airflow Control
Xavier Caubit,1,4 Muriel Thoby-Brisson,2 * Nicolas Voituron,3 * Pierre Filippi,1 * Michelle Bévengut,3 Hervé Faralli,1 Sébastien Zanella,3 Gilles Fortin,2 Gérard Hilaire,3 and Laurent Fasano1
1Unité Mixte de Recherche (UMR) 6216, Centre National de la Recherche Scientifique (CNRS), Université de la Méditerranée, Institut de Biologie du Développement de Marseille Luminy, Parc Scientifique de Luminy, 13288 Marseille Cedex 9, France, 2Neurobiology and Development, Unité Propre de Recherche 3294, Institute of Neurobiology A. Fessard, CNRS, 91198 Gif-sur-Yvette Cedex, France, 3MP3–Respiration, Centre de Recherche en Neurobiologie et Neurophysiologie de Marseille, UMR 6231, CNRS, Université Aix Marseille II and III, Faculté Saint Jér?me, 13397 Marseille Cedex 20, France, and 4Université de Provence, 13331 Marseille, France
Neonatal breathing in mammals involves multiple neuronal circuits, but its genetic basis remains unclear. Mice deficient for the zinc finger protein Teashirt 3 (TSHZ3) fail to breathe and die at birth. Tshz3 is expressed in multiple areas of the brainstem involved in respiration, including the pre-B?tzinger complex (preB?tC), the embryonic parafacial respiratory group (e-pF), and cranial motoneurons that control the upper airways. Tshz3 inactivation led to pronounced cell death of motoneurons in the nucleus ambiguus and induced strong alterations of rhythmogenesis in the e-pF oscillator. In contrast, the preB?tC oscillator appeared to be unaffected. These deficits result in impaired upper airway function, abnormal central respiratory rhythm generation, and altered responses to pH changes. Thus, a single gene, Tshz3, controls the development of diverse components of the circuitry required for breathing.
