Family single-cell atlases reveal pig pregnancy and fetal growth restriction critical cell types

Although massive cell atlases are already available, it is still a challenge to obtain an atlas of all tissues within a single body, especially in fetuses and pregnant mothers. We present a transcriptomic atlas of 2.56 million single cells covering 115 and 119 tissues from one fetal pig and its pregnant mother, respectively. We found that a cluster of heart capillary endothelial cells with enhanced fatty acid transit capability was enriched for pregnancy but restored after gestation. We also deciphered that l-leucine transport insufficiency in the trophoblast causes fetal growth restriction by reducing a muscle type II myofiber subcluster. Our "all-from-one" strategy enabled the identification of tissue cell type-specific transcription factors and provided insights into pregnancy heart adaptation and fetal growth restriction.