Publication details
Neglected taxa shed light on the diversity and evolution of parasitism strategies in Apicomplexa
| Authors | |
|---|---|
| Year of publication | 2024 |
| Type | Conference abstract |
| MU Faculty or unit | |
| Citation | |
| Description | Apicomplexa is a group of very successful parasitic protists, occurring in a wide spectrum of invertebrates and vertebrates. It is assumed that ancestral apicomplexans parasitised marine annelids and then spread to other marine invertebrates followed by freshwater and terrestrial invertebrates, and finally vertebrates. They have evolved unique adaptations for invading and surviving within hosts. This is especially true for the enormously diversified deep-branching groups, which in various ways realise the extracellular, epicellular and intracellular parasitism in different organs and cavities of invertebrates and vertebrates. Basal lineages differ from other Apicomplexa in that their large trophozoites and gamonts are usually motile and their locomotion differs from substrate-dependent, actin/myosin-based gliding described for highly motile apicomplexan zoites. They use several motility mechanisms that represent specific adaptations to parasitism in different environments. In general, apicomplexans demonstrate two main determinative evolutionary trends: i) the origination of epicellular parasitism (gregarines, protococcidia and cryptosporidia), with significant modifications to the attachment apparatus and motility mode at the trophozoite stage; and ii) origination of intracellular parasitism (coccidia and Aconoidasida), accompanied by rejection of trophozoite polarity and motility. We propose a possible scenario for emergence of parasitism in Apicomplexa, where evolution progressed from myzocytotic predation ("cellular vampirism”) to myzocytotic extracellular parasitism, and finally to intracellular parasitism. |
| Related projects: |