Identification and developmental expression of two Tbx1/10-related genes in the agnathan Lethenteron japonicum.
We have identified two Tbx1/10-related genes, LjTbx1/10A and LjTbx1/10B, from the Japanese river lamprey Lethenteron japonicum. We used in situ hybridization to characterize their expression pattern during embryonic development. LjTbx1/10A and LjTbx1/10B shared common expression in the pharyngeal arches and otic vesicle, although their levels and timing of expression differed markedly. LjTbx1/10A was highly expressed in the mesodermal core of pharyngeal arches and the adjacent endoderm throughout pharyngeal arch development, whereas LjTbx1/10B expression was only transiently upregulated in forming pharyngeal pouches. LjTbx1/10A transcripts first appeared at stage 25 in otic vesicles, whereas LjTbx1/10B transcripts could already be detected in the developing otic placode at stage 20. These results suggest that lamprey LjTbx1/10A and LjTbx1/10B may play distinct roles in the patterning and development of the pharyngeal apparatus. It appears that lamprey Tbx1/10 genes have undergone subfunctionalization independent from gnathostomes, with regard to both regulation and function.
Tiecke
Eva
E
Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, B-17, 4259 Nagatsuta-cho, Midori-ku, Yokohama, 226-8501, Japan.
Matsuura
Manami
M
Kokubo
Nobuhiro
N
Kuraku
Shigehiro
S
Kusakabe
Rie
R
Kuratani
Shigeru
S
Tanaka
Mikiko
M
D000818:Animals; D019521:Body Patterning / Q000235:genetics; D001934:Branchial Region / Q000196:embryology / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D019143:Evolution, Molecular; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D007798:Lampreys / Q000196:embryology* / Q000235:genetics*; D005810:Multigene Family; D010802:Phylogeny; D020825:T-Box Domain Proteins / Q000235:genetics*
D018076:DNA, Complementary; D020825:T-Box Domain Proteins