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.
Worden
Alexandra Z
AZ
Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039 USA. azworden@mbari.org
Lee
Jae-Hyeok
JH
Mock
Thomas
T
Rouzé
Pierre
P
Simmons
Melinda P
MP
Aerts
Andrea L
AL
Allen
Andrew E
AE
Cuvelier
Marie L
ML
Derelle
Evelyne
E
Everett
Meredith V
MV
Foulon
Elodie
E
Grimwood
Jane
J
Gundlach
Heidrun
H
Henrissat
Bernard
B
Napoli
Carolyn
C
McDonald
Sarah M
SM
Parker
Micaela S
MS
Rombauts
Stephane
S
Salamov
Aasf
A
Von Dassow
Peter
P
Badger
Jonathan H
JH
Coutinho
Pedro M
PM
Demir
Elif
E
Dubchak
Inna
I
Gentemann
Chelle
C
Eikrem
Wenche
W
Gready
Jill E
JE
John
Uwe
U
Lanier
William
W
Lindquist
Erika A
EA
Lucas
Susan
S
Mayer
Klaus F X
KF
Moreau
Herve
H
Not
Fabrice
F
Otillar
Robert
R
Panaud
Olivier
O
Pangilinan
Jasmyn
J
Paulsen
Ian
I
Piegu
Benoit
B
Poliakov
Aaron
A
Robbens
Steven
S
Schmutz
Jeremy
J
Toulza
Eve
E
Wyss
Tania
T
Zelensky
Alexander
A
Zhou
Kemin
K
Armbrust
E Virginia
EV
Bhattacharya
Debashish
D
Goodenough
Ursula W
UW
Van de Peer
Yves
Y
Grigoriev
Igor V
IV
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