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Msd1/SSX2IP-dependent microtubule anchorage ensures spindle orientation and primary cilia formation.

ABSTRACT: Anchoring microtubules to the centrosome is critical for cell geometry and polarity, yet the molecular mechanism remains unknown. Here we show that the conserved human Msd1/SSX2IP is required for microtubule anchoring. hMsd1/SSX2IP is delivered to the centrosome in a centriolar satellite-dependent manner and binds the microtubule-nucleator ?-tubulin complex. hMsd1/SSX2IP depletion leads to disorganised interphase microtubules and misoriented mitotic spindles with reduced length and intensity. Furthermore, hMsd1/SSX2IP is essential for ciliogenesis, and during zebrafish embryogenesis, knockdown of its orthologue results in ciliary defects and disturbs left-right asymmetry. We propose that the Msd1 family comprises conserved microtubule-anchoring proteins.

SUBMITTER: Hori A

PROVIDER: S-EPMC3989863 | biostudies-other | 2014 Feb

REPOSITORIES: biostudies-other

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Msd1/SSX2IP-dependent microtubule anchorage ensures spindle orientation and primary cilia formation.

Hori Akiko A Ikebe Chiho C Tada Masazumi M Toda Takashi T

EMBO reports 20140107 2

Anchoring microtubules to the centrosome is critical for cell geometry and polarity, yet the molecular mechanism remains unknown. Here we show that the conserved human Msd1/SSX2IP is required for microtubule anchoring. hMsd1/SSX2IP is delivered to the centrosome in a centriolar satellite-dependent manner and binds the microtubule-nucleator γ-tubulin complex. hMsd1/SSX2IP depletion leads to disorganised interphase microtubules and misoriented mitotic spindles with reduced length and intensity. Fu ...[more]

PMID: 24397932

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