Cloning and characterization of a novel gene promoting ureteric bud branching in the metanephros.
BACKGROUND
The ureteric buds and metanephric mesenchymal cells reciprocally induce each other's maturation during kidney development, and implicated transcription factors, secreted growth factors, and cell surface signaling peptides are critical regulators of renal branching morphogenesis. Protein kinase C (PKC) is a key enzyme in the signal transduction mechanisms in various biologic processes, including development, because it regulates growth and differentiation. Inhibition of PKC by the sphingolipid product ceramide interferes with nephron formation in the developing kidney, but the molecule that controls ureteric bud branching downstream of PKC is still unknown.


METHODS
Differential display polymerase chain reaction (PCR) of metanephroi cultured with a PKC activator and inhibitor was performed. We also examined the role of a novel gene in kidney development with organ culture system.


RESULTS
A novel gene encoding a 759 bp mRNA was identified, and we named it metanephros-derived tubulogenic factor (MTF)/L47. Inhibition of MTF with antisense oligonucleotide impaired ureteric bud branching by cultured metanephroi, and addition of recombinant MTF protein promoted ureteric bud branching in cultured metanephroi and increased cell proliferation.


CONCLUSIONS
We identified a novel molecule in developing kidney that is capable of modulating ureteric bud branching and kidney differentiation.
Araki
Takashi
T
Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan.
Hayashi
Matsuhiko
M
Saruta
Takao
T
D000375:Aging / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D002455:Cell Division / Q000187:drug effects; D003001:Cloning, Molecular; D004622:Embryo, Mammalian / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D005314:Embryonic and Fetal Development / Q000235:genetics; D004789:Enzyme Activation / Q000502:physiology; D058851:GPI-Linked Proteins; D018507:Gene Expression Regulation, Developmental; D007668:Kidney / Q000196:embryology* / Q000254:growth & development / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology; D008667:Metalloproteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology; D009924:Organ Culture Techniques; D011493:Protein Kinase C / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D012269:Ribosomal Proteins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology; D014018:Tissue Distribution; D014513:Ureter / Q000196:embryology*
D058851:GPI-Linked Proteins; C425068:Meltf protein, mouse; D008565:Membrane Proteins; D008667:Metalloproteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012269:Ribosomal Proteins; C487702:metanephros-derived tubulogenic factor, human; C487703:metanephros-derived tubulogenic factor, mouse; D011493:Protein Kinase C