A BBSome subunit links ciliogenesis, microtubule stability, and acetylation

Area of Science:

• Cell Biology
• Genetics
• Developmental Biology

Background:

• Primary cilia are vital for organ development and homeostasis.
• Dysfunction of primary cilia is implicated in Bardet-Biedl syndrome (BBS).
• The BBSome complex is essential for primary cilia function, particularly in membrane trafficking.

Purpose of the Study:

• To identify novel components of the BBSome complex.
• To investigate the function of the newly discovered BBSome subunit, BBIP10.
• To elucidate the role of BBIP10 in primary cilia and microtubule regulation.

Main Methods:

• Protein complex analysis to identify BBSome subunits.
• Localization studies using immunofluorescence.
• Gene depletion experiments in zebrafish and cell culture models.
• Microtubule polymerization and acetylation assays.
• Co-immunoprecipitation to study protein interactions.

Main Results:

• BBIP10 was identified as a novel subunit of the BBSome complex.
• BBIP10 localizes to the primary cilium and is conserved in ciliated organisms.
• Depletion of BBIP10 in zebrafish resulted in BBS-like phenotypes.
• BBIP10 is unexpectedly required for cytoplasmic microtubule polymerization and acetylation.
• BBIP10 physically interacts with HDAC6, a tubulin deacetylase, and its inhibition restores microtubule acetylation.

Conclusions:

• BBIP10 is a critical BBSome subunit involved in primary cilia formation and function.
• BBIP10 plays a novel role in regulating microtubule dynamics, distinct from other BBSome subunits.
• BBIP10 may link BBSome-mediated ciliary membrane growth to microtubule acetylation via interaction with HDAC6.