Glucokinase: from allosteric glucose sensing to disease variants

Area of Science:

• Biochemistry
• Molecular Biology
• Metabolic Regulation

Background:

• Human glucokinase (GCK) acts as a critical glucose sensor in pancreatic and liver cells.
• GCK regulates insulin secretion and glycogen synthesis, key processes in glucose homeostasis.
• The enzyme's unique kinetic properties, including low glucose affinity and sigmoidal kinetics, are crucial for its sensing function.

Purpose of the Study:

• To review the structure and function of human glucokinase (GCK).
• To explore the link between GCK's kinetic properties, conformational dynamics, and its role as a glucose sensor.
• To summarize recent large-scale efforts evaluating the effects of GCK genetic variants on glucose homeostasis.

Main Methods:

• Review of existing literature on human glucokinase.
• Analysis of kinetic properties and conformational dynamics of GCK.
• Summary of studies assessing GCK genetic variants and their impact on disease.

Main Results:

• GCK's low affinity for glucose and sigmoidal kinetics enable cellular responsiveness to glucose fluctuations.
• Enzyme dynamics are intrinsically tied to its unusual kinetic behavior.
• Genetic variants impacting GCK function are associated with three major glucose homeostasis disorders.

Conclusions:

• Human glucokinase is a vital glucose sensor due to its unique biochemical properties.
• Understanding GCK dynamics and variant effects is crucial for comprehending glucose metabolism and related diseases.
• Ongoing research focuses on comprehensive assessment of GCK variants to elucidate their clinical significance.