期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2003
卷号：100
期号：4
页码：1763-1768
DOI：10.1073/pnas.0437920100
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Retinoic acid (RA), the active derivative of vitamin A, is involved in various developmental and homeostatic processes. To define whether certain developmental events are particularly sensitive to a decrease in embryonic RA levels, we generated mice bearing a hypomorphic allele of the RA-synthesizing enzyme Raldh2. The resulting mutant mice, which die perinatally, exhibit the features of the human DiGeorge syndrome (DGS) with heart outflow tract septation defects and anomalies of the aortic arch-derived head and neck arteries, laryngeal-tracheal cartilage defects, and thymus/parathyroid aplasia or hypoplasia. Analysis of Raldh2 hypomorph embryos reveal selective defects of the posterior (third to sixth) branchial arches, including absence or hypoplasia of the corresponding aortic arches and pharyngeal pouches, and local down-regulation of RA-target genes. Thus, a decreased level of embryonic RA (through genetic and/or nutritional causes) could represent a major modifier of the expressivity of human 22q11del-associated DiGeorge/velocardiofacial syndromes and, if severe enough, could on its own lead to the clinical features of the DiGeorge syndrome.
