son is necessary for proper vertebrate blood development.

Area of Science:

• Developmental Biology
• Hematology
• Genetics

Background:

• The SON gene, located on human chromosome 21, is implicated in hematopoietic disorders associated with Down syndrome.
• SON functions as an RNA splicing factor involved in transcribing leukemia-related genes.
• Previous research demonstrated SON mutations cause developmental defects in human and zebrafish spines and brains.

Purpose of the Study:

• To investigate the role of SON in normal hematopoiesis (blood formation) during early development.
• To determine the specific blood cell types affected by reduced SON expression in zebrafish.

Main Methods:

• Reduced SON gene expression in zebrafish embryos using specific morpholinos at the single-cell developmental stage.
• Utilized transgenic zebrafish lines (lcr:GFP, cd41:GFP, mpx:GFP, lck:GFP) to visualize and quantify different blood cell populations.
• Assessed the colony-forming capability of hematopoietic stem and progenitor cells (HSPCs) in SON-knockdown zebrafish.

Main Results:

• SON knockdown led to abnormal blood cell levels, including reduced red blood cells, thrombocytes, myeloid cells, and T cells.
• Despite altered blood cell differentiation, the colony-forming capacity of HSPCs remained unaffected.
• Observed concurrent brain and spinal malformations alongside hematological abnormalities.

Conclusions:

• SON is essential for the proper differentiation of innate and adaptive immune cells.
• Further research into the molecular pathways of SON during blood development is needed to understand vertebrate HSPC generation, proliferation, and differentiation.