Lo Liching, Dormand Emma L, Anderson David J
Division of Biology 216-76, California Institute of Technology, Pasadena, CA 91125, USA.
Proc Natl Acad Sci U S A. 2005 May 17;102(20):7192-7. doi: 10.1073/pnas.0502581102. Epub 2005 May 9.
Lineage-tracing experiments have shown that some premigratory neural crest cells generate both sensory (S) and autonomic (A) derivatives, whereas others generate only S derivatives. Whether this lineage heterogeneity reflects random variation in a homogeneous population or an early sensory specification of some premigratory crest cells has not been clear. Using Cre recombinase-based fate mapping, we show that GDF7, which is exclusively expressed in the roof plate, marks neural crest cells with a 10-fold higher bias to the sensory lineage than those marked (at the same stage of development) by an inducible Wnt1-Cre, which is expressed more broadly in the dorsal neural tube. In vitro, GDF7 has potent sensory neuron-inducing activity. These data suggest that some premigratory crest cells are deterministically restricted to the S lineage and implicate GDF7 itself in this restriction process.
谱系追踪实验表明,一些迁移前的神经嵴细胞会产生感觉(S)和自主(A)两种衍生物,而其他细胞则仅产生感觉衍生物。这种谱系异质性是反映了同质群体中的随机变异,还是某些迁移前嵴细胞的早期感觉特化,目前尚不清楚。利用基于Cre重组酶的命运图谱,我们发现,仅在顶板中表达的GDF7标记的神经嵴细胞向感觉谱系分化的倾向比(在相同发育阶段)由诱导型Wnt1-Cre标记的细胞高10倍,后者在背侧神经管中表达更为广泛。在体外,GDF7具有强大的感觉神经元诱导活性。这些数据表明,一些迁移前的嵴细胞被确定性地限制在感觉谱系中,并且意味着GDF7本身参与了这一限制过程。