Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
Department of Neuroscience, Columbia University, New York, NY 10027, USA.
Science. 2022 Sep 2;377(6610):eabp9186. doi: 10.1126/science.abp9186.
The evolution of advanced cognition in vertebrates is associated with two independent innovations in the forebrain: the six-layered neocortex in mammals and the dorsal ventricular ridge (DVR) in sauropsids (reptiles and birds). How these innovations arose in vertebrate ancestors remains unclear. To reconstruct forebrain evolution in tetrapods, we built a cell-type atlas of the telencephalon of the salamander . Our molecular, developmental, and connectivity data indicate that parts of the sauropsid DVR trace back to tetrapod ancestors. By contrast, the salamander dorsal pallium is devoid of cellular and molecular characteristics of the mammalian neocortex yet shares similarities with the entorhinal cortex and subiculum. Our findings chart the series of innovations that resulted in the emergence of the mammalian six-layered neocortex and the sauropsid DVR.
哺乳动物的六层新皮质和蜥形类动物（爬行动物和鸟类）的背侧脑室嵴（DVR）。这些创新在脊椎动物祖先中是如何产生的尚不清楚。为了重建四足动物的前脑进化，我们构建了蝾螈端脑的细胞类型图谱。我们的分子、发育和连接数据表明，部分蜥形类动物的 DVR 可以追溯到四足动物的祖先。相比之下，蝾螈的背侧大脑皮层缺乏哺乳动物新皮质的细胞和分子特征，但与内嗅皮层和下托相似。我们的研究结果描绘了一系列创新，导致了哺乳动物六层新皮质和蜥形类动物 DVR 的出现。
