Structural insights into SHIP2 reveal its membrane regulatory mechanisms

Area of Science:

• Biochemistry
• Molecular Biology
• Cell Biology

Background:

• Src homology 2 domain-containing inositol-5 phosphatase 2 (SHIP2) is crucial for phosphoinositide signaling.
• SHIP2 modulates cellular functions like proliferation, adhesion, migration, and survival.
• SHIP2's dysregulation is implicated in cancer and neurodegenerative diseases, including Alzheimer's.

Purpose of the Study:

• To elucidate the molecular mechanism of SHIP2.
• To determine the cryogenic electron microscopy (cryoEM) structure of SHIP2.
• To understand how SHIP2's structure relates to its function and regulation.

Main Methods:

• Cryogenic electron microscopy (cryoEM) to solve the structure of SHIP2.
• Biochemical assays to study substrate interaction.
• Lipid interaction studies to investigate membrane association.

Main Results:

• The cryoEM structure revealed an unexpected association between SHIP2's pleckstrin homology-related domain and its C2 and phosphatase domains.
• This domain arrangement facilitates substrate interaction, particularly at higher phosphoinositide concentrations.
• SHIP2 was observed to form oligomers on cell membranes.

Conclusions:

• SHIP2 activity is regulated by its domain organization and interactions with membrane lipids.
• The structural insights provide a mechanistic understanding of SHIP2's role in various physiological and pathological conditions.
• This study lays the groundwork for further investigation into SHIP2-targeted therapies.