Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle.
As an obligatory parasite of humans, the body louse (Pediculus humanus humanus) is an important vector for human diseases, including epidemic typhus, relapsing fever, and trench fever. Here, we present genome sequences of the body louse and its primary bacterial endosymbiont Candidatus Riesia pediculicola. The body louse has the smallest known insect genome, spanning 108 Mb. Despite its status as an obligate parasite, it retains a remarkably complete basal insect repertoire of 10,773 protein-coding genes and 57 microRNAs. Representing hemimetabolous insects, the genome of the body louse thus provides a reference for studies of holometabolous insects. Compared with other insect genomes, the body louse genome contains significantly fewer genes associated with environmental sensing and response, including odorant and gustatory receptors and detoxifying enzymes. The unique architecture of the 18 minicircular mitochondrial chromosomes of the body louse may be linked to the loss of the gene encoding the mitochondrial single-stranded DNA binding protein. The genome of the obligatory louse endosymbiont Candidatus Riesia pediculicola encodes less than 600 genes on a short, linear chromosome and a circular plasmid. The plasmid harbors a unique arrangement of genes required for the synthesis of pantothenate, an essential vitamin deficient in the louse diet. The human body louse, its primary endosymbiont, and the bacterial pathogens that it vectors all possess genomes reduced in size compared with their free-living close relatives. Thus, the body louse genome project offers unique information and tools to use in advancing understanding of coevolution among vectors, symbionts, and pathogens.
Kirkness
Ewen F
EF
J Craig Venter Institute, Rockville, MD 20850, USA.
Haas
Brian J
BJ
Sun
Weilin
W
Braig
Henk R
HR
Perotti
M Alejandra
MA
Clark
John M
JM
Lee
Si Hyeock
SH
Robertson
Hugh M
HM
Kennedy
Ryan C
RC
Elhaik
Eran
E
Gerlach
Daniel
D
Kriventseva
Evgenia V
EV
Elsik
Christine G
CG
Graur
Dan
D
Hill
Catherine A
CA
Veenstra
Jan A
JA
Walenz
Brian
B
Tubío
José Manuel C
JM
Ribeiro
José M C
JM
Rozas
Julio
J
Johnston
J Spencer
JS
Reese
Justin T
JT
Popadic
Aleksandar
A
Tojo
Marta
M
Raoult
Didier
D
Reed
David L
DL
Tomoyasu
Yoshinori
Y
Kraus
Emily
E
Krause
Emily
E
Mittapalli
Omprakash
O
Margam
Venu M
VM
Li
Hong-Mei
HM
Meyer
Jason M
JM
Johnson
Reed M
RM
Romero-Severson
Jeanne
J
Vanzee
Janice Pagel
JP
Alvarez-Ponce
David
D
Vieira
Filipe G
FG
Aguadé
Montserrat
M
Guirao-Rico
Sara
S
Anzola
Juan M
JM
Yoon
Kyong S
KS
Strycharz
Joseph P
JP
Unger
Maria F
MF
Christley
Scott
S
Lobo
Neil F
NF
Seufferheld
Manfredo J
MJ
Wang
Naikuan
N
Dasch
Gregory A
GA
Struchiner
Claudio J
CJ
Madey
Greg
G
Hannick
Linda I
LI
Bidwell
Shelby
S
Joardar
Vinita
V
Caler
Elisabet
E
Shao
Renfu
R
Barker
Stephen C
SC
Cameron
Stephen
S
Bruggner
Robert V
RV
Regier
Allison
A
Johnson
Justin
J
Viswanathan
Lakshmi
L
Utterback
Terry R
TR
Sutton
Granger G
GG
Lawson
Daniel
D
Waterhouse
Robert M
RM
Venter
J Craig
JC
Strausberg
Robert L
RL
Berenbaum
May R
MR
Collins
Frank H
FH
Zdobnov
Evgeny M
EM
Pittendrigh
Barry R
BR
D000818:Animals; D004755:Enterobacteriaceae / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D017344:Genes, Insect / Q000235:genetics; D016680:Genome, Bacterial / Q000235:genetics*; D049750:Genome, Insect / Q000235:genetics*; D023281:Genomics / Q000379:methods; D006801:Humans; D010373:Lice Infestations / Q000469:parasitology; D008969:Molecular Sequence Data; D010374:Pediculus / Q000235:genetics* / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D013559:Symbiosis