Dictyostelium discoideum and the other dictyostelid slime moulds (‘social amoebae’) are popular model organisms best known for their demonstration of sorocarpic development. In this process, many cells aggregate to form a multicellular unit that ultimately becomes a fruiting body bearing asexual spores. Several other unrelated microorganisms undergo comparable processes, and in some it is evident that their multicellular development evolved from the differentiation process of encystation. While it has been argued that the dictyostelid fruiting body had similar origins, it has also been proposed that dictyostelid sorocarpy evolved from the unicellular fruiting process found in other amoebozoan slime moulds. This paper reviews the developmental biology of the dictyostelids and other relevant organisms and reassesses the two hypotheses on the evolutionary origins of dictyostelid development. Recent advances in phylogeny, genetics, and genomics and transcriptomics indicate that further research is necessary to determine whether or not the fruiting bodies of the dictyostelids and their closest relatives, the myxomycetes and protosporangids, are homologous.

中文翻译：

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dictyostelid 粘菌子实体的两个潜在进化起源

Dictyostelium discoideum 和其他 dictyostelid 粘液霉菌（“社会变形虫”）是流行的模式生物，以其对 sorocarpic 发育的展示而闻名。在这个过程中，许多细胞聚集形成一个多细胞单元，最终成为带有无性孢子的子实体。其他几种不相关的微生物经历了类似的过程，在某些情况下，很明显它们的多细胞发育是从包囊分化过程进化而来的。虽然有人认为 dictyostelid 子实体具有相似的起源，但也有人提出 dictyostelid sorocarpy 从其他变形虫粘液霉菌中发现的单细胞结果过程进化而来。这篇论文回顾了 dictyostelids 和其他相关生物的发育生物学，并重新评估了关于 dictyostelid 发育进化起源的两种假设。系统发育、遗传学、基因组学和转录组学的最新进展表明，需要进一步研究以确定 dictyostelids 及其近亲、粘菌纲和原孢子囊纲的子实体是否同源。