PUBLICATION

ß-thymosin is required for axonal tract formation in developing zebrafish brain

Authors
Roth, L.W., Bormann, P., Bonnet, A., and Reinhard, E.
ID
ZDB-PUB-990511-20
Date
1999
Source
Development (Cambridge, England)   126(7): 1365-1374 (Journal)
Registered Authors
Reinhard, Eva, Roth, Lukas
Keywords
ß-thymosin; zebrafish; neuronal growth; muscle differentiation; actin; antisense injections
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Axons/metabolism
  • Base Sequence
  • Brain/embryology
  • Cloning, Molecular
  • Gene Expression Regulation, Developmental/genetics
  • Homeodomain Proteins/genetics
  • Immunohistochemistry
  • In Situ Hybridization
  • LIM-Homeodomain Proteins
  • Molecular Sequence Data
  • Muscles/embryology
  • Nerve Tissue Proteins*
  • Nervous System/embryology
  • RNA/genetics
  • RNA, Antisense/pharmacology
  • Sequence Alignment
  • Thymosin/chemistry
  • Thymosin/genetics*
  • Transcription Factors
  • Zebrafish/embryology
  • Zebrafish/genetics*
PubMed
10068630 Full text @ Development
Abstract
ß-Thymosins are polypeptides that bind monomeric actin and thereby function as actin buffers in many cells. We show that during zebrafish development, ß-thymosin expression is tightly correlated with neuronal growth and differentiation. It is transiently expressed in a subset of axon-extending neurons, essentially primary neurons that extend long axons, glia and muscle. Non-neuronal expression in the brain is restricted to a subset of glia surrounding newly forming axonal tracts. Skeletal muscle cells in somites, jaw and fin express ß-thymosin during differentiation, coinciding with the time of innervation. Injection of ß-thymosin antisense RNA into zebrafish embryos results in brain defects and impairment of the development of ß-thymosin-associated axon tracts. Furthermore, irregularities in somite formation can be seen in a subset of embryos. Compared to wild-type, antisense-injected embryos show slightly weaker and more diffuse engrailed staining at the midbrain-hindbrain boundary and a strong reduction of Isl-1 labeling in Rohon Beard and trigeminal neurons. The decreased expression is not based on a loss of neurons indicating that ß-thymosin may be involved in the maintenance of the expression of molecules necessary for neuronal differentiation. Taken together, our results strongly indicate that ß-thymosin is an important regulator of development.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping