Eumycetozoa = Amoebozoa?: SSUrDNA phylogeny of protosteloid slime molds and its significance for the amoebozoan supergroup.
Amoebae that make fruiting bodies consisting of a stalk and spores and classified as closely related to the myxogastrids have classically been placed in the taxon Eumycetozoa. Traditionally, there are three groups comprising Eumycetozoa: myxogastrids, dictyostelids, and the so-called protostelids. Dictyostelids and myxogastrids both make multicellular fruiting bodies that may contain hundreds of spores. Protostelids are those amoebae that make simple fruiting bodies consisting of a stalk and one or a few spores. Protostelid-like organisms have been suggested as the progenitors of the myxogastrids and dictyostelids, and they have been used to formulate hypotheses on the evolution of fruiting within the group. Molecular phylogenies have been published for both myxogastrids and dictyostelids, but little molecular phylogenetic work has been done on the protostelids. Here we provide phylogenetic trees based on the small subunit ribosomal RNA gene (SSU) that include 21 protostelids along with publicly available sequences from a wide variety of amoebae and other eukaryotes. SSU trees recover seven well supported clades that contain protostelids but do not appear to be specifically related to one another and are often interspersed among established groups of amoebae that have never been reported to fruit. In fact, we show that at least two taxa unambiguously belong to amoebozoan lineages where fruiting has never been reported. These analyses indicate that we can reject a monophyletic Eumycetozoa, s.l. For this reason, we will hereafter refer to those slime molds with simple fruiting as protosteloid amoebae and/or protosteloid slime molds, not as protostelids. These results add to our understanding of amoebozoan biodiversity, and demonstrate that the paradigms for understanding both nonfruiting and sporulating amoebae must be integrated. Finally, we suggest strategies for future research on protosteloid amoebae and nonfruiting amoebae, and discuss the impact of this work for taxonomists and phylogenomicists.
Shadwick
Lora L
LL
Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA. lora.lindley@gmail.com
Spiegel
Frederick W
FW
Shadwick
John D L
JD
Brown
Matthew W
MW
Silberman
Jeffrey D
JD
D000818:Animals; D004275:DNA, Ribosomal / Q000235:genetics*; D016013:Likelihood Functions; D056895:Mycetozoa / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction
D004275:DNA, Ribosomal
Proc Natl Acad Sci U S A. 1997 Oct 28;94(22):12007-12
9342353
Mol Phylogenet Evol. 2008 Apr;47(1):339-52
18180171
Protist. 2005 Aug;156(2):215-24
16171188
Mycologia. 2006 Jan-Feb;98(1):144-8
16800313
Mol Biol Evol. 1999 Dec;16(12):1740-51
10605115
Syst Biol. 2002 Jun;51(3):492-508
12079646
Mycologia. 2002 Nov-Dec;94(6):968-79
21156570
Mol Biol Evol. 1999 Sep;16(9):1270-9
10939894
Science. 2006 Oct 27;314(5799):661-3
17068267
Bioinformatics. 2006 Nov 1;22(21):2688-90
16928733
Mol Biol Evol. 2001 Dec;18(12):2306-14
11719580
J Eukaryot Microbiol. 2005 Sep-Oct;52(5):399-451
16248873
Eur J Protistol. 2008 Feb;44(1):35-44
17905574
J Protozool. 1969 Aug;16(3):437-41
4898844
J Eukaryot Microbiol. 2005 May-Jun;52(3):201-10
15926995
Syst Biol. 2004 Oct;53(5):793-808
15545256
Bioinformatics. 2001 Dec;17(12):1246-7
11751242
Protist. 2009 Feb;160(1):21-40
19036635
J Protozool. 1978 Feb;25(1):44-9
566326
Proc Natl Acad Sci U S A. 2002 Feb 5;99(3):1414-9
11830664
Biol Rev Camb Philos Soc. 1998 Aug;73(3):203-66
9809012
J Eukaryot Microbiol. 2009 Jan-Feb;56(1):16-25
19335771
Biosystems. 1991;25(1-2):113-20
1854909
Mol Biol Evol. 2003 Nov;20(11):1881-6
12949141
Protist. 2007 Jul;158(3):295-324
17602867
BMC Evol Biol. 2008 Jan 18;8:14
18205932
Protist. 2005 Aug;156(2):191-202
16171186
J Protozool. 1966 Feb;13(1):164-71
5330308
BMC Evol Biol. 2007 Nov 08;7:214
17996036
Gene. 1988 Nov 30;71(2):491-9
3224833
Int J Syst Evol Microbiol. 2006 Jun;56(Pt 6):1449-1458
16738126
J Eukaryot Microbiol. 2006 Nov-Dec;53(6):522-30
17123417
J Eukaryot Microbiol. 2007 Nov-Dec;54(6):511-9
18070328
Science. 2000 Nov 3;290(5493):972-7
11062127
Bioinformatics. 1998;14(9):817-8
9918953
Biosystems. 1985;18(3-4):377-86
4084680
Biosystems. 1981;14(3-4):491-9
7337821
Bioinformatics. 2003 Aug 12;19(12):1572-4
12912839
PLoS Genet. 2006 Dec;2(12):e220
17194223