Rohon-Beard neuron origin from blastomeres of the 16-cell frog embryo.
نویسنده
چکیده
Clonal origins of Rohon-Beard neurons in Xenopus were determined quantitatively by injecting horseradish peroxidase into individual blastomeres at the 16-cell stage and later counting labeled and unlabeled Rohon-Beard neurons. Two different patterns of cleavage were selected. In pattern X, all Rohon-Beard neurons originated from three blastomeres (V1.1, V1.2, and V2.2) on each side; in pattern Y, all Rohon Beard neurons originated from two blastomeres (V1.2 and V2.2) on each side. Counts of Rohon-Beard neurons at larval stages 32 to 34 showed that 96 to 100% (mean 99%) originated from blastomeres on the same side; of these, 68 to 90% (mean 75%) descended from V1.2, 20 to 31% (mean 24%) descended from V2.2, 0 to 7% descended from V1.1. The significance of the regionally restricted origin of Rohon-Beard neurons is discussed.
منابع مشابه
Rohon-Beard neurons arise from a substitute ancestral cell after removal of the cell from which they normally arise in the 16-cell frog embryo.
In 16-cell Xenopus embryos, horseradish peroxidase (HRP) was injected into blastomere D1.2 on one side. No Rohon-Beard neurons originated from D1.2 in either of the two patterns of cleavage that were studied (Jacobson, M. (1981) J. Neurosci. 1: 918-922). In other embryos, after injection of HRP into D1.2, the neighboring ventral blastomere V1.2, from which 68 to 90% of Rohon-Beard neurons norma...
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ورودعنوان ژورنال:
- The Journal of neuroscience : the official journal of the Society for Neuroscience
دوره 1 8 شماره
صفحات -
تاریخ انتشار 1981