Genomic analysis finds no evidence of canonical eukaryotic DNA processing complexes in a free-living protist

TY - JOUR

T1 - Genomic analysis finds no evidence of canonical eukaryotic DNA processing complexes in a free-living protist

AU - Salas-Leiva, Dayana E

AU - Tromer, Eelco C

AU - Curtis, Bruce A

AU - Jerlström-Hultqvist, Jon

AU - Kolisko, Martin

AU - Yi, Zhenzhen

AU - Salas-Leiva, Joan S

AU - Gallot-Lavallée, Lucie

AU - Williams, Shelby K

AU - Kops, Geert J P L

AU - Archibald, John M

AU - Simpson, Alastair G B

AU - Roger, Andrew J

N1 - © 2021. The Author(s).

PY - 2021/10/14

Y1 - 2021/10/14

N2 - Cells replicate and segregate their DNA with precision. Previous studies showed that these regulated cell-cycle processes were present in the last eukaryotic common ancestor and that their core molecular parts are conserved across eukaryotes. However, some metamonad parasites have secondarily lost components of the DNA processing and segregation apparatuses. To clarify the evolutionary history of these systems in these unusual eukaryotes, we generated a genome assembly for the free-living metamonad Carpediemonas membranifera and carried out a comparative genomics analysis. Here, we show that parasitic and free-living metamonads harbor an incomplete set of proteins for processing and segregating DNA. Unexpectedly, Carpediemonas species are further streamlined, lacking the origin recognition complex, Cdc6 and most structural kinetochore subunits. Carpediemonas species are thus the first known eukaryotes that appear to lack this suite of conserved complexes, suggesting that they likely rely on yet-to-be-discovered or alternative mechanisms to carry out these fundamental processes.

AB - Cells replicate and segregate their DNA with precision. Previous studies showed that these regulated cell-cycle processes were present in the last eukaryotic common ancestor and that their core molecular parts are conserved across eukaryotes. However, some metamonad parasites have secondarily lost components of the DNA processing and segregation apparatuses. To clarify the evolutionary history of these systems in these unusual eukaryotes, we generated a genome assembly for the free-living metamonad Carpediemonas membranifera and carried out a comparative genomics analysis. Here, we show that parasitic and free-living metamonads harbor an incomplete set of proteins for processing and segregating DNA. Unexpectedly, Carpediemonas species are further streamlined, lacking the origin recognition complex, Cdc6 and most structural kinetochore subunits. Carpediemonas species are thus the first known eukaryotes that appear to lack this suite of conserved complexes, suggesting that they likely rely on yet-to-be-discovered or alternative mechanisms to carry out these fundamental processes.

KW - Animals

KW - Biological Evolution

KW - DNA/metabolism

KW - Eukaryota/genetics

KW - Eukaryotic Cells/metabolism

KW - Genome

KW - Genomics

KW - Microbiology

KW - Parasites/genetics

KW - Proteins/genetics

U2 - 10.1038/s41467-021-26077-2

DO - 10.1038/s41467-021-26077-2

M3 - Article

C2 - 34650064

SN - 2041-1723

VL - 12

SP - 6003

JO - Nature Communications

JF - Nature Communications

IS - 1

ER -