Inositol Pyrophosphates as Versatile Metabolic Messengers.

Area of Science:

• Cellular metabolism
• Molecular signaling
• Biochemistry

Background:

• Inositol pyrophosphates (IPs) are evolutionarily conserved signaling metabolites.
• Their roles as energy regulators, phosphodonors, and signaling messengers are increasingly recognized.
• Enzymes metabolizing IPs are crucial for understanding their cellular functions.

Purpose of the Study:

• To review the catalytic and regulatory mechanisms of inositol pyrophosphates kinases (IP6Ks) and diphosphoinositol pentakisphosphate kinases (PPIP5Ks).
• To elucidate the functions of IPs in cellular and physiological processes.
• To highlight evidence for IPs' role in mammalian metabolic homeostasis.

Main Methods:

• Review of current literature on IP6Ks and PPIP5Ks.
• Analysis of enzymatic pathways involving inositol pyrophosphates.
• Examination of genetic and cellular evidence.

Main Results:

• Inositol pyrophosphates, particularly 5-IP7 and IP8, are synthesized by IP6Ks and PPIP5Ks.
• These molecules regulate phosphate homeostasis, ATP synthesis, insulin secretion, and energy utilization.
• IPs are implicated as essential mediators of mammalian metabolic homeostasis.

Conclusions:

• Inositol pyrophosphates play diverse and critical roles in cellular energy regulation and metabolic homeostasis.
• Understanding the enzymes that synthesize and degrade IPs is key to deciphering their physiological significance.
• Further research into IPs promises insights into metabolic diseases and therapeutic strategies.