Expression of the zebrafish recognition molecule F3/F11/contactin in a subset of differentiating neurons is regulated by cofactors associated with LIM domains.
We have identified a zebrafish homolog of the F3/F11/contactin (F3) recognition molecule. The gene shares 55% amino acid identity with F3 molecules in other vertebrates. Expression of F3 mRNA is first detectable at 16 h post-fertilization (hpf) in trigeminal and Rohon-Beard neurons. At 18-24 hpf, additional weaker expression is present in discrete cell clusters in the hindbrain, in the anterior lateral line/acoustic ganglion and in spinal motor neurons. Transcription factors of the LIM homeodomain class (LIM-HD) and their associated cofactors CLIM/NLI/Ldb (CLIM) have been implicated in the development of peripheral axons of trigeminal and Rohon-Beard neurons. We demonstrate that ectopic overexpression of a dominant-negative CLIM molecule early during zebrafish development strongly reduces expression of F3 mRNA in these neurons indicating regulation of F3 by the LIM-HD protein network. These results and the spatiotemporal correlation of F3 expression with axonal differentiation in a subset of primary neurons suggest an important role of F3 for axon growth.
Gimnopoulos
Dimitrios
D
Zentrum für Molekulare Neurobiologie Hamburg, Universität Hamburg, Martinistrasse 52, D-20246 Hamburg, Germany.
Becker
Catherina G
CG
Ostendorff
Heather P
HP
Bach
Ingolf
I
Schachner
Melitta
M
Becker
Thomas
T
D000595:Amino Acid Sequence; D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000096:biosynthesis / Q000235:genetics*; D002454:Cell Differentiation / Q000502:physiology*; D058966:Contactins; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D014157:Transcription Factors / Q000378:metabolism; D012668:Trigeminal Ganglion / Q000378:metabolism; D015027:Zebrafish / Q000196:embryology / Q000235:genetics*
D015816:Cell Adhesion Molecules, Neuronal; D058966:Contactins; D014157:Transcription Factors