Understanding the mechanisms that control tooth replacement

了解控制牙齿更换的机制

• 批准号: BB/W00240X/1
• 负责人: Abigail Tucker
• 金额: $ 60.71万
• 依托单位: King's College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FW00240X%2F1
• 关键词: Understanding; mechanisms; control; tooth; replacement

As a child losing a tooth is a cause for celebration with a visit from the tooth fairy. Later in life, tooth loss becomes a significant issue, with the prospect of implants, bridges, and dentures. This is because as mammals we only have two sets of teeth, our baby (deciduous) teeth, and our permanent teeth. This brings the question of why we have this restriction when elsewhere in the animal kingdom sharks, snakes and crocodiles have a seemingly unlimited supply of replacement teeth. Here we aim to understand the mechanisms that restrict tooth number in mammals by investigating the signals that determine whether a tooth is replaced or not. For this, we will study replacement in an animal that does not replace its teeth (the mouse) and a mammal that replaces some of its teeth (the opossum) and compare to a reptile that constantly replaces its teeth (the corn snake) and a reptile that only has one set of teeth (the chameleon). We have previously shown that in the mouse the first tooth inhibits the formation of a replacement tooth. Here we ask what those signals are (Aim 1). We know that neighbouring teeth in the opossum have different replacement capacity but we don't know what drives these differences, to make one tooth replace and one tooth not (Aim 2). Snake teeth replace each other in a tightly packed chain, so the inhibition observed in mammals doesn't occur. What changed during the evolution of mammals? Are the signals that restrict tooth number in mammals shared across toothed animals or are the rules for tooth replacement distinct in mammals compared to reptiles (Aim3). This knowledge will provide the foundation for an understanding of the mechanisms that control tooth replacement strategies, providing the possibility of controlling tooth numbers in the future. For example, if we understood how the first tooth inhibits the replacement tooth and causes its deterioration, we could prevent this from happening and reawaken tooth replacement potential. This will be particularly important in instances where non-replacing permanent teeth deteriorate prior to the end of an animal's lifespan.

作为一个孩子，失去一颗牙齿是一个庆祝的理由，牙仙的访问。在以后的生活中，牙齿脱落成为一个重要的问题，种植体，桥梁和假牙的前景。这是因为作为哺乳动物，我们只有两套牙齿，我们的乳牙（乳牙）和恒牙。这就带来了一个问题，为什么我们有这种限制，而在其他动物王国鲨鱼，蛇和鳄鱼似乎有无限的替代牙齿供应。在这里，我们的目标是通过研究决定牙齿是否被替换的信号来了解限制哺乳动物牙齿数量的机制。为此，我们将研究一种不更换牙齿的动物（老鼠）和一种更换部分牙齿的哺乳动物（负鼠），并与一种不断更换牙齿的爬行动物（玉米蛇）和一种只有一套牙齿的爬行动物（变色龙）进行比较。我们之前已经证明，在小鼠中，第一颗牙齿会抑制替换牙齿的形成。在这里，我们问这些信号是什么（目标1）。我们知道负鼠的相邻牙齿具有不同的替换能力，但我们不知道是什么驱动了这些差异，使一颗牙齿替换而另一颗牙齿不替换（目标2）。蛇的牙齿在紧密排列的链条中相互替换，因此在哺乳动物中观察到的抑制作用不会发生。哺乳动物进化过程中发生了什么变化？限制哺乳动物牙齿数量的信号是否在有齿动物中共享，或者与爬行动物相比，哺乳动物的牙齿替换规则是否不同（Aim3）。这些知识将为理解控制牙齿替换策略的机制提供基础，为将来控制牙齿数量提供可能性。例如，如果我们了解第一颗牙齿如何抑制替换牙齿并导致其退化，我们就可以防止这种情况发生并重新唤醒牙齿替换潜力。这在非替换性恒牙在动物寿命结束前退化的情况下尤其重要。

项目成果

A conserved tooth resorption mechanism in modern and fossil snakes.

• DOI: 10.1038/s41467-023-36422-2
• 发表时间: 2023-02-10
• 期刊: NATURE COMMUNICATIONS
• 影响因子: 16.6
• 作者: LeBlanc, A. R. H.;Palci, A.;Anthwal, N.;Tucker, A. S.;Araujo, R.;Pereira, M. F. C.;Caldwell, M. W.
• 通讯作者: Caldwell, M. W.

Getting out of a mammalian egg: the egg tooth and caruncle of the echidna.

从哺乳动物的蛋中取出：针鼹的蛋牙和肉阜。

• DOI: 10.1016/j.ydbio.2022.12.005
• 发表时间: 2023
• 期刊: Developmental biology
• 影响因子: 2.7
• 作者: Fenelon JC