The duplicated paired box protein 7 (pax7) genes differentially transcribed during Japanese flounder (Paralichthys olivaceus) embryogenesis.
PAX are important regulators of developmental processes. PAX7 plays crucial roles in patterning of the dorsal central nervous system (CNS), neural crest (NC), and skeletal muscle. Here, we identified six spliced isoforms of pax7a and one pax7b and characterized their expression patterns. All of flounder Pax7a-1, Pax7a-2, Pax7a-3, and Pax7b contain a conserved paired domain (PD), an octapeptide motif (OP), and a paired type homeodomain (HD). However, the PD of Pax7a-4 and the HD of Pax7a-5 are not intact, and there is no HD in Pax7a-4 and Pax7a-6. pax7a and pax7b show distinct spatiotemporal expression patterns during embryogenesis. Whole-mount in situ hybridization demonstrates that the expression patterns of pax7a and pax7b are overlapping but distinguishable in the dorsal central nervous system. pax7a is expressed in most part of the brain and the neural tube, while pax7b is expressed exclusively in the diencephalon and the midbrain. In addition, pax7a is also expressed in the cranial NC and the trunk NC. RT-PCR results show that there were different expression patterns between the different isoforms. These results indicate subfunction partitioning of the duplicated pax7 genes. The duplicated pax7 may provide additional flexibility in fine-tuning neurogenesis and somitogenesis.
Key Laboratory of Experimental Marine Biology, National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, Shandong 266071, People's Republic of China.
Shuang
S
Jiao
Key Laboratory of Experimental Marine Biology, National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, Shandong 266071, People's Republic of China. Electronic address: tanx@qdio.ac.cn.
Xungang
X
Tan
Key Laboratory of Experimental Marine Biology, National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, Shandong 266071, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Meijie
M
Li
Key Laboratory of Experimental Marine Biology, National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, Shandong 266071, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Yulei
Y
Sui
Department of Biochemistry and Molecular Biology, School of Medicine, University of Maryland, 701 E. Pratt St., Baltimore, MD 21202, USA.
Shao Jun
SJ
Du
Key Laboratory of Experimental Marine Biology, National and Local Joint Engineering Laboratory of Ecological Mariculture, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, Shandong 266071, People's Republic of China.
Feng
F
You
D000818:Animals; D001921:Brain / Q000378:metabolism; D047108:Embryonic Development; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005432:Flounder / Q000196:embryology* / Q000235:genetics* / Q000378:metabolism; D020131:Genes, Duplicate; D018398:Homeodomain Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D024510:Muscle Development; D051763:PAX7 Transcription Factor / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D020033:Protein Isoforms / Q000737:chemistry; D017434:Protein Structure, Tertiary; D014158:Transcription, Genetic
D029941:Fish Proteins; D018398:Homeodomain Proteins; D051763:PAX7 Transcription Factor; D020033:Protein Isoforms
Dermomyotome; Expression pattern; Pax7a; Pax7b; Spliced isoforms