Phylogenetic distribution of neuron-specific enolase

Area of Science:

• Biochemistry
• Neuroscience
• Cell Biology

Background:

• Neurons and neuroendocrine cells possess a distinct glycolytic enzyme isoenzyme.
• This acidic isoenzyme is termed neuron specific enolase (NSE).
• NSE is identifiable via DEAE sephadex elution, distinguishing it from other enolases.

Purpose of the Study:

• To investigate the presence of neuron specific enolase (NSE) in lower species.
• To determine if the acidic enolase isoenzyme is unique to mammalian or higher vertebrates.

Main Methods:

• Analysis of brain tissue from various species including yeast, fish, and frog.
• Enolase isoenzyme characterization, likely involving chromatographic techniques like DEAE sephadex elution.

Main Results:

• Lower species (yeast, fish, frog) brain tissue showed no significant levels of acidic "NSE-like" enolase.
• The unique acidic enolase isoenzyme characteristic of mammalian neurons was not detected.

Conclusions:

• The specific acidic enolase isoenzyme, neuron specific enolase (NSE), is not present in the analyzed lower species.
• This finding suggests that NSE is a marker specific to more evolved neuronal systems, likely absent in primitive organisms.