Nusap1 is essential for neural crest cell migration in zebrafish.

Area of Science:

• Developmental Biology
• Cell Biology
• Genetics

Background:

• Microtubules are vital for cell division and chromosome segregation.
• Microtubule-associated proteins' in vivo functions are poorly understood due to limited animal models.
• Nucleolar spindle-associated protein (NuSAP) is implicated in mitosis from cell culture studies.

Purpose of the Study:

• To identify and characterize the zebrafish homologue of human NuSAP (nusap1).
• To investigate the expression profile and functional significance of nusap1 in vivo.
• To elucidate the role of Nusap1 in vertebrate development and morphogenesis.

Main Methods:

• In situ hybridization to determine nusap1 transcript expression patterns.
• Antisense oligonucleotide morpholino technology for in vivo gene knockdown.
• Analysis of neural crest, blood vessel, and notochord marker expression.
• Apoptosis assays following nusap1 mRNA injection and rescue experiments.

Main Results:

• Zebrafish nusap1 transcripts are specifically expressed in the retina, forebrain, hindbrain, and neural crest.
• nusap1 knockdown resulted in impaired trunk and yolk extension morphogenesis, suggesting a role in cell migration.
• nusap1 morphants showed altered neural crest marker expression but normal blood vessel and notochord marker expression.
• nusap1 mRNA injection induced apoptosis in retinal and hindbrain tissues, which was rescued by morpholino co-injection.

Conclusions:

• Zebrafish Nusap1 plays a significant role in neural crest cell migration and vertebrate morphogenesis.
• Nusap1 appears to link apoptosis with cell migration processes during development.
• These findings highlight the in vivo importance of Nusap1 in vertebrate development.