Gruner Hannah N, Pickett C J, Bao Jasmine Yimeng, Garcia Richard, Hozumi Akiko, Scully Tal, Ning Shaoyang, Gao Mavis, Bautista Gia, Maze Keren, Lim Karissa, Osugi Tomohiro, Collins-Doijode Mae, Cairns Ofubofu, Levis Gabriel, Chen Shu Yi, Gong TaiXi, Satake Honoo, Moshe-Klein Allon, Gigante Eduardo D, Sasakura Yasunori, Davidson Bradley
Swarthmore College, Department of Biology, 500 College Ave, Swarthmore, PA 19081, USA.
Shimoda Marine Research Center, University of Tsukuba, 5-10-1, Shimoda, Shizuoka, 415-0025, Japan.
bioRxiv. 2025 May 2:2025.04.28.651085. doi: 10.1101/2025.04.28.651085.
Neurons contribute to the complex interplay of signals that mediate heart development and homeostasis. Although a limited set of studies suggest that neuronal peptides impact vertebrate heart growth, the specific contributions of these peptides to cardiomyocyte progenitor differentiation or proliferation have not been elucidated. Here we show that the neuropeptide tachykinin along with canonical Wnt signaling regulate cardiomyocyte progenitor proliferation in the chordate model . In , the heart continues to grow throughout adulthood and classic histological studies indicate that a line of undifferentiated cells may serve as a reserve progenitor lineage. We found that this line of cardiomyocyte progenitors consists of distinct distal and midline populations. Distal progenitors divide asymmetrically to produce distal and midline daughters. Midline progenitors divide asymmetrically to produce myocardial precursors. Through single cell RNA sequencing (scRNA-seq) of adult hearts, we delineated the cardiomyocyte progenitor expression profile. Based on this data we investigated the role of Wnt signaling in cardiomyocyte progenitor proliferation and found that canonical Wnt signaling is required to suppress excessive progenitor proliferation. The scRNA-seq data also identified a number of presumptive cardiac neural-like cells. Strikingly, we found that a subset of these neuronal cells appears to innervate the distal cardiomyocyte progenitors. Based on the expression of the tachykinin receptor in these neuronal cells, we blocked tachykinin signaling using pharmacological inhibitors and found that this drove reduced proliferation in the distal progenitor pool. Through targeted CRISPR-Cas9 knockdown we then demonstrated that both extrinsic tachykinin and intrinsic, cardiac tachykinin receptors are required for formation of the myocardial heart tube. This work provides valuable insights into how organisms may deploy neural signals to regulate organ growth in response to environmental or homeostatic inputs.
神经元参与介导心脏发育和内稳态的信号复杂相互作用。尽管有限的一系列研究表明神经肽会影响脊椎动物心脏生长，但这些肽对心肌祖细胞分化或增殖的具体作用尚未阐明。在这里，我们表明神经肽速激肽与经典Wnt信号通路一起调节脊索动物模型中的心肌祖细胞增殖。在该模型中，心脏在成年期持续生长，经典组织学研究表明，一排未分化细胞可能作为储备祖细胞谱系。我们发现，这一心肌祖细胞谱系由不同的远端和中线群体组成。远端祖细胞不对称分裂产生远端和中线子代细胞。中线祖细胞不对称分裂产生心肌前体细胞。通过对成年心脏进行单细胞RNA测序（scRNA-seq），我们描绘了心肌祖细胞的表达谱。基于这些数据，我们研究了Wnt信号通路在心肌祖细胞增殖中的作用，发现经典Wnt信号通路对于抑制过度的祖细胞增殖是必需的。scRNA-seq数据还鉴定出一些推定的心脏神经样细胞。令人惊讶的是，我们发现这些神经元细胞的一个子集似乎支配着远端心肌祖细胞。基于这些神经元细胞中速激肽受体的表达，我们使用药理学抑制剂阻断速激肽信号通路，发现这导致远端祖细胞池中的增殖减少。然后，通过靶向CRISPR-Cas9敲低，我们证明外在的速激肽和内在的心脏速激肽受体对于心肌心管的形成都是必需的。这项工作为生物体如何利用神经信号来响应环境或内稳态输入调节器官生长提供了有价值的见解。
