A saturation screen for cis-acting regulatory DNA in the Hox genes of Ciona intestinalis.
A screen for the systematic identification of cis-regulatory elements within large (>100 kb) genomic domains containing Hox genes was performed by using the basal chordate Ciona intestinalis. Randomly generated DNA fragments from bacterial artificial chromosomes containing two clusters of Hox genes were inserted into a vector upstream of a minimal promoter and lacZ reporter gene. A total of 222 resultant fusion genes were separately electroporated into fertilized eggs, and their regulatory activities were monitored in larvae. In sum, 21 separable cis-regulatory elements were found. These include eight Hox linked domains that drive expression in nested anterior-posterior domains of ectodermally derived tissues. In addition to vertebrate-like CNS regulation, the discovery of cis-regulatory domains that drive epidermal transcription suggests that C. intestinalis has arthropod-like Hox patterning in the epidermis.
Keys
David N
DN
U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA.
Lee
Byung-in
BI
Di Gregorio
Anna
A
Harafuji
Naoe
N
Detter
J Chris
JC
Wang
Mei
M
Kahsai
Orsalem
O
Ahn
Sylvia
S
Zhang
Cindy
C
Doyle
Sharon A
SA
Satoh
Noriyuki
N
Satou
Yutaka
Y
Saiga
Hidetoshi
H
Christian
Allen T
AT
Rokhsar
Dan S
DS
Hawkins
Trevor L
TL
Levine
Mike
M
Richardson
Paul M
PM
D000818:Animals; D022202:Chromosomes, Artificial, Bacterial; D002938:Ciona intestinalis / Q000235:genetics*; D004353:Drug Evaluation, Preclinical / Q000379:methods; D018274:Electroporation; D004817:Epidermis / Q000378:metabolism; D005801:Genes, Homeobox / Q000235:genetics*; D005822:Genetic Vectors; D007814:Larva / Q000235:genetics; D008722:Methods; D008969:Molecular Sequence Data; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D014158:Transcription, Genetic; D015053:Zygote