Interaction between Poly(ADP-ribose) and NuMA Contributes to Mitotic Spindle Pole Assembly

Abstract

Poly(ADP-ribose) (pADPr), made by PARP-5a/tankyrase-1, localizes to the poles of mitotic spindles and is required for bipolar spindle assembly, but its molecular function in the spindle is poorly understood. To investigate this, we localized pADPr at spindle poles by immuno-EM. We then developed a concentrated mitotic lysate system from HeLa cells to probe spindle pole assembly in vitro. Microtubule asters assembled in response to centrosomes and Ran-GTP in this system. Magnetic beads coated with pADPr, extended from PARP-5a, also triggered aster assembly, suggesting a functional role of the pADPr in spindle pole assembly. We found that PARP-5a is much more active in mitosis than interphase. We used mitotic PARP-5a, self-modified with pADPr chains, to capture mitosis-specific pADPr-binding proteins. Candidate binding proteins included the spindle pole protein NuMA previously shown to bind to PARP-5a directly. The rod domain of NuMA, expressed in bacteria, bound directly to pADPr. We propose that pADPr provides a dynamic cross-linking function at spindle poles by extending from covalent modification sites on PARP-5a and NuMA and binding noncovalently to NuMA and that this function helps promote assembly of exactly two poles.

Tankyrase-1 function at telomeres and during mitosis is regulated by Polo-like kinase-1-mediated phosphorylation

“…Interestingly, PARsylation of NuMA by TNKS1 seems to influence the structural integrity of spindle poles and may be essential for protein interactions required for spindle formation. [21][22][23] Together, these findings indicate that TNKS1 might be an essential enzyme responsible for providing poly(ADP-ribose) to the spindle assembly during mitosis and regulating mitotic cell-cycle progression.…”

“…Recent work has also indicated that poly(ADP-ribose) appears to be a key component of mitotic spindle assembly and structure. 8,21 TNKS1 colocalizes with the nuclear mitotic apparatus (NuMA) protein at the spindle poles during mitosis. 22 Localization of TNKS1 at the spindle pole is dependent on the NuMA protein.…”

Small-Molecule Chemical Probe Rescues Cells from Mono-ADP-Ribosyltransferase ARTD10/PARP10-Induced Apoptosis and Sensitizes Cancer Cells to DNA Damage

“…While some ARTDs modify substrates by transferring iteratively multiple ADP-ribose units resulting in poly-ADP-ribosylation (PARylation), most ARTDs mono-ADP-ribosylate (MARylate) their substrates (Kleine et al, 2008). ARTDs function in DNA damage repair (Malanga and Althaus, 2005;Nicolae et al, 2014Nicolae et al, , 2015, the unfolded protein response (Jwa and Chang, 2012), apoptosis Koh et al, 2005), heat shock (Petesch and Lis, 2008), cellular signaling (Feijs et al, 2013a;, cell division (Chang et al, 2004(Chang et al, , 2005(Chang et al, , 2009Ha et al, 2012), as well as transcription and chromatin regulation Schreiber et al, 2006). PARylating ARTDs (pARTDs; ARTD1-6), most prominently ARTD1, have been the focus of cancer related research during the past two decades.…”

Niacin requirements for genomic stability

“…In addition to regulating telomerase activity and telomere length, tankyrases work with PARP-3 in the maintenance of telomere integrity [25]. Tankyrase-1 has been found to be active in the process of mitotic spindle pole assembly, during which automodification of tankyrase-1 gathers additional proteins through high affinity binding to the cloud of PAR [27]. Again, niacin deficiency could induce various forms of genomic instability through decreased tankyrase activities, and this remains uncharacterized.…”