Chick embryo nerve growth factor. Fractionation and biological activity

Area of Science:

• Developmental biology
• Neuroscience
• Biochemistry

Background:

• Nerve growth factor (NGF) is essential for neuronal development and survival.
• Previous studies suggested the presence of NGF in avian species, but direct evidence was limited.

Purpose of the Study:

• To isolate and characterize a nerve growth factor (NGF)-like protein from developing chick embryos.
• To confirm the biological activity and structural similarity of chick embryo NGF to mammalian NGF.

Main Methods:

• Partial purification of NGF-like factor using cation-exchange and hydrophobic interaction chromatography.
• Activation of the factor using gel filtration in 6 M urea.
• Analysis by SDS-PAGE, immunoblotting with anti-mouse beta NGF antibodies, and bioassays.

Main Results:

• A partially purified NGF-like factor was obtained from 18-day chick embryo extract.
• The factor's activity was enhanced by gel filtration in urea.
• Immunoblotting and bioassays demonstrated antigenic cross-reactivity and functional similarity to mouse beta NGF.
• The molecular weight of the chick embryo NGF was determined to be approximately 14,000 Da, similar to mouse beta NGF.

Conclusions:

• Biologically active nerve growth factor (NGF) protein is present in the developing 18-day chick embryo.
• The chick embryo NGF shares antigenic and structural properties with mouse beta NGF, indicating evolutionary conservation.
• These findings provide direct evidence for NGF in avian embryonic development.