| Title |
Kingdom Chromista and its eight phyla: a new synthesis emphasising periplastid protein targeting, cytoskeletal and periplastid evolution, and ancient divergences
|
|---|---|
| Published in |
Protoplasma, September 2017
|
| DOI | 10.1007/s00709-017-1147-3 |
| Pubmed ID | |
| Authors |
Thomas Cavalier-Smith |
| Abstract |
In 1981 I established kingdom Chromista, distinguished from Plantae because of its more complex chloroplast-associated membrane topology and rigid tubular multipartite ciliary hairs. Plantae originated by converting a cyanobacterium to chloroplasts with Toc/Tic translocons; most evolved cell walls early, thereby losing phagotrophy. Chromists originated by enslaving a phagocytosed red alga, surrounding plastids by two extra membranes, placing them within the endomembrane system, necessitating novel protein import machineries. Early chromists retained phagotrophy, remaining naked and repeatedly reverted to heterotrophy by losing chloroplasts. Therefore, Chromista include secondary phagoheterotrophs (notably ciliates, many dinoflagellates, Opalozoa, Rhizaria, heliozoans) or walled osmotrophs (Pseudofungi, Labyrinthulea), formerly considered protozoa or fungi respectively, plus endoparasites (e.g. Sporozoa) and all chromophyte algae (other dinoflagellates, chromeroids, ochrophytes, haptophytes, cryptophytes). I discuss their origin, evolutionary diversification, and reasons for making chromists one kingdom despite highly divergent cytoskeletons and trophic modes, including improved explanations for periplastid/chloroplast protein targeting, derlin evolution, and ciliary/cytoskeletal diversification. I conjecture that transit-peptide-receptor-mediated 'endocytosis' from periplastid membranes generates periplastid vesicles that fuse with the arguably derlin-translocon-containing periplastid reticulum (putative red algal trans-Golgi network homologue; present in all chromophytes except dinoflagellates). I explain chromist origin from ancestral corticates and neokaryotes, reappraising tertiary symbiogenesis; a chromist cytoskeletal synapomorphy, a bypassing microtubule band dextral to both centrioles, favoured multiple axopodial origins. I revise chromist higher classification by transferring rhizarian subphylum Endomyxa from Cercozoa to Retaria; establishing retarian subphylum Ectoreta for Foraminifera plus Radiozoa, apicomonad subclasses, new dinozoan classes Myzodinea (grouping Colpovora gen. n., Psammosa), Endodinea, Sulcodinea, and subclass Karlodinia; and ranking heterokont Gyrista as phylum not superphylum. |
X Demographics
The data shown below were collected from the profiles of 29 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Australia | 2 | 7% |
| United States | 2 | 7% |
| Hungary | 1 | 3% |
| Poland | 1 | 3% |
| France | 1 | 3% |
| Spain | 1 | 3% |
| Korea, Democratic People's Republic of | 1 | 3% |
| Chile | 1 | 3% |
| Thailand | 1 | 3% |
| Other | 5 | 17% |
| Unknown | 13 | 45% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 15 | 52% |
| Scientists | 10 | 34% |
| Science communicators (journalists, bloggers, editors) | 2 | 7% |
| Practitioners (doctors, other healthcare professionals) | 1 | 3% |
| Unknown | 1 | 3% |
Mendeley readers
The data shown below were compiled from readership statistics for 273 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 273 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 44 | 16% |
| Student > Ph. D. Student | 36 | 13% |
| Student > Bachelor | 34 | 12% |
| Student > Master | 30 | 11% |
| Student > Doctoral Student | 22 | 8% |
| Other | 34 | 12% |
| Unknown | 73 | 27% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 87 | 32% |
| Biochemistry, Genetics and Molecular Biology | 46 | 17% |
| Environmental Science | 15 | 5% |
| Immunology and Microbiology | 13 | 5% |
| Earth and Planetary Sciences | 8 | 3% |
| Other | 20 | 7% |
| Unknown | 84 | 31% |
Attention Score in Context
This research output has an Altmetric Attention Score of 29. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 14 April 2024.
All research outputs
#1,354,403
of 25,462,162 outputs
Outputs from Protoplasma
#6
of 1,039 outputs
Outputs of similar age
#26,702
of 323,555 outputs
Outputs of similar age from Protoplasma
#1
of 16 outputs
Altmetric has tracked 25,462,162 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 94th percentile: it's in the top 10% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,039 research outputs from this source. They receive a mean Attention Score of 2.8. This one has done particularly well, scoring higher than 99% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 323,555 tracked outputs that were published within six weeks on either side of this one in any source. This one has done particularly well, scoring higher than 91% of its contemporaries.
We're also able to compare this research output to 16 others from the same source and published within six weeks on either side of this one. This one has done particularly well, scoring higher than 99% of its contemporaries.