Stepwise commitment of blast cell fates during the positional specification of the O and P cell lines in the leech embryo.
Stepwise commitment of blast cell fates during the positional specification of the O and P cell lines in the leech embryo.
复制标题
在水蛭胚胎中 O 和 P 细胞系的位置指定过程中，母细胞命运的逐步承诺。
DOI：
10.1016/0012-1606(84)90231-8
复制
发表时间：
1984
影响因子：
2.7
通讯作者：
Weisblat,DA
中科院分区：
文献类型：
--
作者：
Shankland,M;Weisblat,DA
水蛭胚胎的o带和p带是外胚层原始细胞的平行柱，通过它们的相对位置来识别，并且在正常胚胎发生期间遵循不同的发育途径。先前的研究表明，o胚细胞最初能够遵循O或P通路，并建议承诺O通路取决于与相邻的p带的相互作用。为了更好地理解这种相互作用的性质和时间，我们研究了o型母细胞的命运，其p型母细胞的邻居已被选择性地通过荧光谱系示踪剂的光激发消融。如果o母细胞尚未开始二次分裂，则可以通过消融邻近的p带来有效阻止其正常进入O途径。比较逐渐晚期病变的结果显示，o母细胞的后代在一系列三个离散步骤中致力于O通路，并且这些步骤发生在前三个母细胞分裂的时间附近。这三个事件中的每一个都影响原始细胞克隆中不同的元素子集，并且显然将这些元素提交给O或P途径，这取决于其他条带的存在或不存在。胚细胞命运的这些变化与病变沿着带状物的长度共同延伸，表明两个带状物的相互作用局限于相邻细胞。
The o and p bandlets of the leech embryo are parallel columns of ectodermal blast cells which are identified by their relative positions, and which during normal embryogenesis follow distinct developmental pathways. A previous study showed that o blast cells are initially capable of following either the O or P pathway, and suggested that commitment to the O pathway depends upon interaction with the adjacent p bandlet. To better understand the nature and timing of this interaction we examined the fate of o blast cells whose p blast cell neighbors had been selectively ablated by photoexcitation of a fluorescent lineage tracer. If an o blast cell has not yet begun its secondary divisions, its normal commitment to the O pathway can be effectively prevented by ablation of the adjacent p bandlet. Comparing the outcome of progressively later lesions reveals that the progeny of the o blast cell become committed to the O pathway in a series of three discrete steps, and that these steps occur around the time of the first three blast cell divisions. Each of the three events affects a different subset of elements within the blast cell clone, and apparently commits those elements to either the O or P pathway depending upon the presence or absence of the other bandlet. These changes in blast cell fate are coextensive with the lesion along the bandlet's length, suggesting that the interaction of the two bandlets is localized to neighboring cells.