Cytokinin signaling by way of a multistep two-component signaling pathway has been highly examined over the last 20 years with a lot of attention to how its signaling components regulate essential growth and developmental processes from seedlings to senescence. Most studies have focused on Angiosperm plants, particularly Arabidopsis, with very little attention across the rest of the plant kingdom, making it difficult to know if cytokinin-regulated developmental processes are have remained evolutionarily conserved or distinct among different plant groups. Here the prevalence of cytokinin signaling components throughout plants, algae, and other organisms are examined. Particular examination is paid to how minimal sets of these base signaling components are related to development in Bryophytes, a primary group of study outside of Angiosperms. General comparisons of the role of signaling components between these distant groups suggest some evolutionary conservation of function has been maintained across plants as a whole. This review also highlights the need to investigate how cytokinin signaling components, recently identified in every plant group, contribute to development; this will give higher resolution to our understanding of cytokinin roles in development across plant taxa. Also revealed is a strong need to further pursue how cytokinin signaling components recently identified in every plant group contribute to development in order to further dissect these connections.

在过去的 20 年中，通过多步双组分信号传导途径的细胞分裂素信号传导得到了高度的研究，很多关注其信号传导组分如何调节从幼苗到衰老的基本生长和发育过程。大多数研究都集中在被子植物植物，特别是拟南芥上，对植物界其他部分的关注很少，因此很难知道细胞分裂素调节的发育过程是否在不同植物群中保持进化保守或不同。这里检查了植物、藻类和其他生物体中细胞分裂素信号成分的普遍性。特别研究了这些基本信号成分的最小集合如何与苔藓植物的发育相关，苔藓植物是被子植物之外的主要研究组。对这些远距离组之间信号成分作用的一般比较表明，整个植物都保持了一些进化上的功能保守性。本综述还强调需要研究最近在每个植物群中发现的细胞分裂素信号成分如何促进发育；这将为我们对细胞分裂素在植物分类群发育中的作用的理解提供更高的分辨率。还揭示了进一步研究最近在每个植物群中发现的细胞分裂素信号成分如何促进发育以进一步剖析这些联系的强烈需求。本综述还强调需要研究最近在每个植物群中发现的细胞分裂素信号成分如何促进发育；这将为我们对细胞分裂素在植物分类群发育中的作用的理解提供更高的分辨率。还揭示了进一步研究最近在每个植物群中发现的细胞分裂素信号成分如何促进发育以进一步剖析这些联系的强烈需求。本综述还强调需要研究最近在每个植物群中发现的细胞分裂素信号成分如何促进发育；这将为我们对细胞分裂素在植物分类群发育中的作用的理解提供更高的分辨率。还揭示了进一步研究最近在每个植物群中发现的细胞分裂素信号成分如何促进发育以进一步剖析这些联系的强烈需求。