The spindle-associated antisense RNA ARHGEF17-AS1 functionally contributes to mitotic spindle integrity.

Long non-coding RNAs (lncRNAs) are increasingly recognized as regulators of mitotic progression, yet few have been shown to act directly at the mitotic spindle. Here we identify ARHGEF17-AS1 as a metaphase-enriched antisense RNA that localizes to the mitotic spindle and is associated with spindle pole integrity. ARHGEF17-AS1 interacts with RPS3 and the dynein motor complex and is associated with RPS3 recruitment to the mitotic spindle and with the RPS3-dynein interaction. Depletion of ARHGEF17-AS1 reduces this interaction and decreases RPS3 accumulation at spindle poles. ARHGEF17-AS1 depletion is also associated with lower RPS3 abundance, reduced RNF10 expression, and loss of mitosis-associated RPS3 monoubiquitination at lysine 214. These perturbations coincide with altered spindle microtubule organization and delayed mitotic progression. Together, the data support a model in which ARHGEF17-AS1 contributes to spindle organization through an RNA-mediated pathway involving extra-ribosomal RPS3, dynein, and RNF10, supporting an important role for ARHGEF17-AS1 in mitotic spindle organization.