Molecular Signatures of Placentation and Secretion Uncovered in Poeciliopsis Maternal Follicles
Molecular Signatures of Placentation and Secretion Uncovered in Poeciliopsis Maternal Follicles
复制标题
DOI：
10.1093/molbev/msaa121
复制
发表时间：
2020-09-01
影响因子：
10.7
通讯作者：
Baker, Julie C.
中科院分区：
文献类型：
--
作者：
Guernsey, Michael W.;van Kruistum, Henri;Baker, Julie C.
胎盘形成在脊椎动物中独立进化了许多次。尽管所有胎盘的核心功能相似，但我们对这种相似性如何延伸到分子水平知之甚少。在这里，我们研究了Poeciliopsis，这是一种独特的有生命的鱼类，至少三次独立进化出复杂的胎盘结构。母体卵泡是这些结构的关键组成部分。它包裹着富含蛋黄的卵，在卵巢营养型物种中形态简单，但在雌性营养型物种中具有精细的绒毛结构。通过测序，我们发现了两个物种的毛囊转录组，尽管它们的复杂性不同，但它们都是对胎盘功能至关重要的基因。此外，当我们比较不同河流种群的转录组时，我们发现分泌基因在母体卵泡中的绒毛细胞的顶层表达存在差异。这提供了一些最初的证据，证明斜纹夜蛾的胎盘结构是通过分泌机制发挥作用的，而不是直接接触母体循环。最后，当我们观察胎盘蛋白在更大样本中母胎界面的表达时，我们发现关键的母胎胎盘蛋白在所有物种的同源组织类型中都有表达，但催乳素的卵泡表达仅限于基质营养型物种。综上所述，我们认为所有的毛囊都具备胎盘功能，但需要关键基因的表达才能形成分泌绒毛。
Placentation evolved many times independently in vertebrates. Although the core functions of all placentas are similar, we know less about how this similarity extends to the molecular level. Here, we study Poeciliopsis, a unique genus of live-bearing fish that have independently evolved complex placental structures at least three times. The maternal follicle is a key component of these structures. It envelops yolk-rich eggs and is morphologically simple in lecithotrophic species but has elaborate villous structures in matrotrophic species. Through sequencing, the follicle transcriptome of a matrotrophic,H Poeciliopsis retropinna, and lecithotrophic, P. turrubarensis, species we found genes known to be critical for placenta function expressed in both species despite their difference in complexity. Additionally, when we compare the transcriptome of different river populations of P. retropinna, known to vary in maternal provisioning, we find differential expression of secretory genes expressed specifically in the top layer of villi cells in thematernal follicle. This provides some of the first evidence that the placental structures of Poeciliopsis function using a secretory mechanism rather than direct contact with maternal circulation. Finally, when we look at the expression of placenta proteins at the maternal-fetal interface of a larger sampling of Poeciliopsis species, we find expression of key maternal and fetal placenta proteins in their cognate tissue types of all species, but follicle expression of prolactin is restricted to only matrotrophic species. Taken together, we suggest that all Poeciliopsis follicles are poised for placenta function but require expression of key genes to form secretory villi.