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Updated: Jun 26, 2026
10:49
Pre-clinical Evaluation of Tyrosine Kinase Inhibitors for Treatment of Acute Leukemia
Published on: September 19, 2013
Leukocyte tyrosine kinase functions in pigment cell development
Susana S Lopes1, Xueyan Yang, Jeanette Müller
1Centre for Regenerative Medicine, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom.
Plos Genetics
|March 29, 2008
Summary
Leukocyte tyrosine kinase (Ltk) is crucial for specifying iridophores, a type of neural crest cell. This study identifies Ltk
Area of Science:
- Developmental Biology
- Cell Biology
- Genetics
Background:
- Neural crest cells (NCCs) are multipotent precursors whose fate choices are not fully understood.
- Sox10 is known to be essential for neural cell and melanocyte specification from NCCs.
- Zebrafish shady mutants, like sox10 mutants, lack iridophores, suggesting a role for both genes in iridophore development.
Purpose of the Study:
- To identify the gene responsible for the shady mutation.
- To elucidate the role of the identified gene in neural crest cell fate specification, particularly for iridophores.
- To investigate the relationship between Sox10 and the identified gene in iridophore development.
Main Methods:
- Positional cloning and genetic analysis to identify the shady gene.
- Expression analysis of the identified gene in wild-type and mutant zebrafish embryos.
- Cell transplantation experiments to assess the cell autonomy of gene function.
- Analysis of iridophore markers and neural crest cell populations in mutant embryos.
Main Results:
- The shady mutation was identified as encoding zebrafish leukocyte tyrosine kinase (Ltk).
- Ltk acts cell-autonomously in the specification of the iridophore lineage.
- ltk expression is initially found in a subset of NCCs and later restricted to iridophores.
- ltk mutants exhibit a primary defect in iridophore specification, with NCCs undergoing apoptosis rather than fate-shifting.
- sox10 mutants show reduced iridophore markers but an increase in premigratory ltk-expressing cells, suggesting a role for Sox10 in progenitor regulation.
Conclusions:
- Leukocyte tyrosine kinase (Ltk) is essential for the cell-autonomous specification of iridophores from neural crest cells.
- This study reveals a novel signaling pathway in neural crest development and identifies the first specific role for Ltk in iridophore fate determination.
- Sox10 and Ltk function in distinct but potentially related aspects of neural crest development, with Sox10 influencing progenitor populations.
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