Spatio-temporally regulated expression of receptor tyrosine kinases, mRor1, mRor2, during mouse development: implications in development and function of the nervous system.
BACKGROUND
Drosophila neurospecific receptor tyrosine kinases (RTKs), Dror and Dnrk, as well as Ror1 and Ror2 RTKs, isolated from human neuroblastoma, have been identified as a structurally related novel family of RTKs (Ror-family RTKs). Thus far, little is known about the expression and function of mammalian Ror-family RTKs.


RESULTS
We have identified murine Ror-family RTKs, mRor1 and mRor2. Both mRor1 and mRor2 genes are induced upon neuronal differentiation of P19EC cells. During neuronal differentiation in vitro, the expression of mRor2 is transiently induced, although that of mRor1 increases continuously. During embryogenesis, the mRor1 gene is expressed in the developing nervous system within restricted regions and in the developing lens epithelium. The expression of mRor1 is sustained in the nervous system and is also detected in non-neuronal tissues after birth. In contrast, the expression of mRor2 is detected mainly in the developing nervous system within broader regions and declines after birth. Possible relationships of mRor1 and mRor2 genes with previously identified mutants have also been examined.


CONCLUSIONS
The developmental expressions of mRor1 and mRor2, in particular in the nervous system, are differentially regulated, reflecting their expression patterns in vitro. mRor1 and mRor2 may thus play differential roles during the development of the nervous system.
Oishi
I
I
Department of Biochemistry, Kobe University, School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe 650, Japan.
Takeuchi
S
S
Hashimoto
R
R
Nagabukuro
A
A
Ueda
T
T
Liu
Z J
ZJ
Hatta
T
T
Akira
S
S
Matsuda
Y
Y
Yamamura
H
H
Otani
H
H
Minami
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019556:COS Cells; D002455:Cell Division; D002478:Cells, Cultured; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004622:Embryo, Mammalian / Q000033:anatomy & histology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D008040:Genetic Linkage; D006801:Humans; D015151:Immunoblotting; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009420:Nervous System / Q000196:embryology*; D009447:Neuroblastoma / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D020794:Receptor Protein-Tyrosine Kinases; D057050:Receptor Tyrosine Kinase-like Orphan Receptors; D011956:Receptors, Cell Surface / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013997:Time Factors; D014018:Tissue Distribution; D014443:Tyrosine / Q000378:metabolism
D018076:DNA, Complementary; D011956:Receptors, Cell Surface; D014443:Tyrosine; C078716:ROR1 protein, human; C078717:ROR2 protein, human; D020794:Receptor Protein-Tyrosine Kinases; D057050:Receptor Tyrosine Kinase-like Orphan Receptors