Green evolution and dynamic adaptations revealed by genomes of the marine picoeukaryotes Micromonas.
Picoeukaryotes are a taxonomically diverse group of organisms less than 2 micrometers in diameter. Photosynthetic marine picoeukaryotes in the genus Micromonas thrive in ecosystems ranging from tropical to polar and could serve as sentinel organisms for biogeochemical fluxes of modern oceans during climate change. These broadly distributed primary producers belong to an anciently diverged sister clade to land plants. Although Micromonas isolates have high 18S ribosomal RNA gene identity, we found that genomes from two isolates shared only 90% of their predicted genes. Their independent evolutionary paths were emphasized by distinct riboswitch arrangements as well as the discovery of intronic repeat elements in one isolate, and in metagenomic data, but not in other genomes. Divergence appears to have been facilitated by selection and acquisition processes that actively shape the repertoire of genes that are mutually exclusive between the two isolates differently than the core genes. Analyses of the Micromonas genomes offer valuable insights into ecological differentiation and the dynamic nature of early plant evolution.
Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039 USA. azworden@mbari.org
Alexandra Z
AZ
Worden
Jae-Hyeok
JH
Lee
Thomas
T
Mock
Pierre
P
Rouzé
Melinda P
MP
Simmons
Andrea L
AL
Aerts
Andrew E
AE
Allen
Marie L
ML
Cuvelier
Evelyne
E
Derelle
Meredith V
MV
Everett
Elodie
E
Foulon
Jane
J
Grimwood
Heidrun
H
Gundlach
Bernard
B
Henrissat
Carolyn
C
Napoli
Sarah M
SM
McDonald
Micaela S
MS
Parker
Stephane
S
Rombauts
Aasf
A
Salamov
Peter
P
Von Dassow
Jonathan H
JH
Badger
Pedro M
PM
Coutinho
Elif
E
Demir
Inna
I
Dubchak
Chelle
C
Gentemann
Wenche
W
Eikrem
Jill E
JE
Gready
Uwe
U
John
William
W
Lanier
Erika A
EA
Lindquist
Susan
S
Lucas
Klaus F X
KF
Mayer
Herve
H
Moreau
Fabrice
F
Not
Robert
R
Otillar
Olivier
O
Panaud
Jasmyn
J
Pangilinan
Ian
I
Paulsen
Benoit
B
Piegu
Aaron
A
Poliakov
Steven
S
Robbens
Jeremy
J
Schmutz
Eve
E
Toulza
Tania
T
Wyss
Alexander
A
Zelensky
Kemin
K
Zhou
E Virginia
EV
Armbrust
Debashish
D
Bhattacharya
Ursula W
UW
Goodenough
Yves
Y
Van de Peer
Igor V
IV
Grigoriev
D000222:Adaptation, Physiological; D005075:Biological Evolution; D000460:Chlorophyta / Q000145:classification / Q000166:cytology / Q000235:genetics* / Q000502:physiology; D004251:DNA Transposable Elements; D017753:Ecosystem; D005786:Gene Expression Regulation; D005796:Genes; D014644:Genetic Variation; D016678:Genome; D007438:Introns; D008540:Meiosis / Q000235:genetics; D008969:Molecular Sequence Data; D009792:Oceans and Seas; D010788:Photosynthesis / Q000235:genetics; D010802:Phylogeny; D010839:Phytoplankton / Q000145:classification / Q000235:genetics; D010944:Plants / Q000235:genetics*; D022661:RNA, Untranslated; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics
D004251:DNA Transposable Elements; D022661:RNA, Untranslated; D014157:Transcription Factors