RNA-binding motif 5 (RBM5) is a pro-death tumor suppressor gene in cancer cells. It remains to be determined if it is neurotoxic in the brain or rather if it plays a fundamentally different role in the central nervous system (CNS). Brain-specific RBM5 knockout (KO) mice were given a controlled cortical impact (CCI) traumatic brain injury (TBI). Markers of acute cellular damage and repair were measured in hippocampal homogenates 48 h post-CCI. Hippocampal CA1/CA3 cell counts were assessed 7 days post-CCI to determine if early changes in injury markers were associated with histological outcome. No genotype-dependent differences were found in the levels of apoptotic markers (caspase 3, caspase 6, and caspase 9). However, KO females had a paradoxical increase in markers of pro-death calpain activation (145/150-spectrin and breakdown products [SBDP]) and in DNA repair/survival markers. (pH2A.x and pCREB). CCI-injured male KOs had a significant increase in phosphorylated calcium/calmodulin-dependent protein kinase II (pCaMKII). Despite sex/genotype-dependent differences in KOs in the levels of acute cell signaling targets involved in cell death pathways, 7 day hippocampal neuronal survival did not differ from that of wild types (WTs). Similarly, no differences in astrogliosis were observed. Finally, gene analysis revealed increased estrogen receptor α (ERα) levels in the KO hippocampus in females and may suggest a novel mechanism to explain sex-dimorphic effects on cell signaling. In summary, RBM5 inhibition did not affect hippocampal survival after a TBI in vivo but did modify targets involved in neural signal transduction/Ca2+ signaling pathways. Findings here support the view that RBM5 may serve a purpose in the CNS that is dissimilar from its traditional pro-death role in cancer.
Get full access to this article
View all access options for this article.
References
1.
JacksonT.C., and KochanekP.M. (2020). RNA binding motif 5 (RBM5) in the CNS-moving beyond cancer to harness RNA splicing to mitigate the consequences of brain injury. Front. Mol. Neurosci. 13, 126.
2.
OhJ.J., RazfarA., DelgadoI., ReedR.A., MalkinaA., BoctorB., and SlamonD.J. (2006). 3p21.3 tumor suppressor gene H37/Luca15/RBM5 inhibits growth of human lung cancer cells through cell cycle arrest and apoptosis. Cancer Res. 66, 3419–3427.
3.
FushimiK., RayP., KarA., WangL., SutherlandL.C., and WuJ.Y. (2008). Up-regulation of the proapoptotic caspase 2 splicing isoform by a candidate tumor suppressor, RBM5. Proc. Natl. Acad. Sci. U. S. A. 105, 15, 708–15,713.
4.
KobayashiT., IshidaJ., MusashiM., OtaS., YoshidaT., ShimizuY., ChumaM., KawakamiH., AsakaM., TanakaJ., ImamuraM., KobayashiM., ItohH., EdamatsuH., SutherlandL.C., and BrachmannR.K. (2011). p53 transactivation is involved in the antiproliferative activity of the putative tumor suppressor RBM5. Int. J. Cancer, 128, 304–318.
5.
Rintala-MakiN.D., and SutherlandL.C. (2004). LUCA-15/RBM5, a putative tumour suppressor, enhances multiple receptor-initiated death signals. Apoptosis, 9, 475–484.
6.
Mourtada-MaarabouniM., SutherlandL.C., and WilliamsG.T. (2002). Candidate tumour suppressor LUCA-15 can regulate multiple apoptotic pathways. Apoptosis, 7, 421–432.
7.
O'BryanM.K., ClarkB.J., McLaughlinE.A., D'SylvaR.J., O'DonnellL., WilceJ.A., SutherlandJ., O'ConnorA.E., WhittleB., GoodnowC.C., OrmandyC.J., and JamsaiD. (2013). RBM5 is a male germ cell splicing factor and is required for spermatid differentiation and male fertility. PLoS Genet. 9, e1003628.
8.
JacksonT.C., Janesko-FeldmanK., GorseK., VagniV.A., JacksonE.K., and KochanekP.M. (2020). Identification of novel targets of RBM5 in the healthy and injured brain. Neuroscience, 440, 299–315.
9.
KaeserP.S., DengL., FanM., and SudhofT.C. (2012). RIM genes differentially contribute to organizing presynaptic release sites. Proc. Natl. Acad. Sci. U. S. A. 109, 11, 830–11,835.
10.
JacksonT.C., KotermanskiS.E., and KochanekP.M. (2017). Whole-transcriptome microarray analysis reveals regulation of Rab4 by RBM5 in neurons. Neuroscience, 361, 93–107.
11.
JacksonT.C., DuL., Janesko-FeldmanK., VagniV.A., DezfulianC., PoloyacS.M., JacksonE.K., ClarkR.S., and KochanekP.M. (2015). The nuclear splicing factor RNA binding motif 5 promotes caspase activation in human neuronal cells, and increases after traumatic brain injury in mice. J. Cereb. Blood Flow Metab. 35, 655–666.
12.
ZhangJ., CuiZ., FengG., BaoG., XuG., SunY., WangL., ChenJ., JinH., LiuJ., YangL., and LiW. (2015). RBM5 and p53 expression after rat spinal cord injury: implications for neuronal apoptosis. Int. J. Biochem. Cell Biol. 60, 43–52.
13.
JacksonT.C., KotermanskiS.E., JacksonE.K., and KochanekP.M. (2018). BrainPhys(R) increases neurofilament levels in CNS cultures, and facilitates investigation of axonal damage after a mechanical stretch-injury in vitro. Exp. Neurol. 300, 232–246.
14.
JacksonT.C., KotermanskiS.E., and KochanekP.M. (2018). Infants uniquely express high levels of RBM3 and other cold-adaptive neuroprotectant proteins in the human brain. Dev. Neurosci. 40, 325–336.
15.
JacksonT.C., GorseK., HerrmannJ.R., and KochanekP.M. (2021). Hippocampal and prefrontal cortical brain tissue levels of irisin and GDF15 receptor subunits in children. Mol. Neurobiol. 58, 2145–2157.
16.
HemerkaJ.N., WuX., DixonC.E., GarmanR.H., ExoJ.L., ShellingtonD.K., BlasioleB., VagniV.A., Janesko-FeldmanK., XuM., WisniewskiS.R., BayirH., JenkinsL.W., ClarkR.S., TishermanS.A., and KochanekP.M. (2012). Severe brief pressure-controlled hemorrhagic shock after traumatic brain injury exacerbates functional deficits and long-term neuropathological damage in mice. J. Neurotrauma, 29, 2192–2208.
17.
JacksonT.C., DixonC.E., Janesko-FeldmanK., VagniV., KotermanskiS.E., JacksonE.K., and KochanekP.M. (2018). Acute physiology and neurologic outcomes after brain injury in SCOP/PHLPP1 KO mice. Sci. Rep. 8, 7158.
18.
FrankowskiJ.C., KimY.J., and HuntR.F. (2019). Selective vulnerability of hippocampal interneurons to graded traumatic brain injury. Neurobiol. Dis. 129, 208–216.
19.
PatelA.D., GerzanichV., GengZ., and SimardJ.M. (2010). Glibenclamide reduces hippocampal injury and preserves rapid spatial learning in a model of traumatic brain injury. J. Neuropathol. Exp. Neurol. 69, 1177–1190.
20.
WangK., BaconM.L., TessierJ.J., Rintala-MakiN.D., TangV., and SutherlandL.C. (2012). RBM10 modulates apoptosis and influences TNF-alpha gene expression. J. Cell Death, 5, 1–19.
BrustovetskyT., BolshakovA., and BrustovetskyN. (2010). Calpain activation and Na+/Ca2+ exchanger degradation occur downstream of calcium deregulation in hippocampal neurons exposed to excitotoxic glutamate. J. Neurosci. Res. 88, 1317–1328.
23.
PikeB.R., FlintJ., DaveJ.R., LuX.C., WangK.K., TortellaF.C., and HayesR.L. (2004). Accumulation of calpain and caspase-3 proteolytic fragments of brain-derived alphaII-spectrin in cerebral spinal fluid after middle cerebral artery occlusion in rats. J. Cereb. Blood Flow Metab. 24, 98–106.
24.
BrophyG.M., PinedaJ.A., PapaL., LewisS.B., ValadkaA.B., HannayH.J., HeatonS.C., DemeryJ.A., LiuM.C., TepasJ.J., 3rdGabrielli, A., RobicsekS., WangK.K., RobertsonC.S., and HayesR.L. (2009). alphaII-Spectrin breakdown product cerebrospinal fluid exposure metrics suggest differences in cellular injury mechanisms after severe traumatic brain injury. J. Neurotrauma, 26, 471–479.
25.
AshpoleN.M., and HudmonA. (2011). Excitotoxic neuroprotection and vulnerability with CaMKII inhibition. Mol. Cell Neurosci. 46, 720–730.
26.
DengG., OrfilaJ.E., DietzR.M., Moreno-GarciaM., RodgersK.M., CoultrapS.J., QuillinanN., TraystmanR.J., BayerK.U., and HersonP.S. (2017). Autonomous CaMKII activity as a drug target for histological and functional neuroprotection after resuscitation from cardiac arrest. Cell Rep. 18, 1109–1117.
27.
KornhauserJ.M., CowanC.W., ShaywitzA.J., DolmetschR.E., GriffithE.C., HuL.S., HaddadC., XiaZ., and GreenbergM.E. (2002). CREB transcriptional activity in neurons is regulated by multiple, calcium-specific phosphorylation events. Neuron, 34, 221–233.
28.
YanX., LiuJ., YeZ., HuangJ., HeF., XiaoW., HuX., and LuoZ. (2016). CaMKII-mediated CREB phosphorylation is involved in Ca2+-induced BDNF mRNA transcription and neurite outgrowth promoted by electrical stimulation. PLoS One, 11, e0162784.
29.
HeffnerC.S., Herbert PrattC., BabiukR.P., SharmaY., RockwoodS.F., DonahueL.R., EppigJ.T., and MurrayS.A. (2012). Supporting conditional mouse mutagenesis with a comprehensive cre characterization resource. Nat. Commun. 3, 1218.
30.
KossW.A., and FrickK.M. (2017). Sex differences in hippocampal function. J. Neurosci. Res. 95, 539–562.
31.
AbrahamI.M., and HerbisonA.E. (2005). Major sex differences in non-genomic estrogen actions on intracellular signaling in mouse brain in vivo. Neuroscience, 131, 945–951.
32.
DayN.L., FloydC.L., D'AlessandroT.L., HubbardW.J., and ChaudryI.H. (2013). 17beta-estradiol confers protection after traumatic brain injury in the rat and involves activation of G protein-coupled estrogen receptor 1. J. Neurotrauma, 30, 1531–1541.
33.
BiegonA. (2021). Considering biological sex in traumatic brain injury. Front. Neurol. 12,, 576, 366.
34.
DanielP., FilizG., BrownD.V., HollandeF., GonzalesM., D'AbacoG., PapalexisN., PhillipsW.A., MalaterreJ., RamsayR.G., and MantamadiotisT. (2014). Selective CREB-dependent cyclin expression mediated by the PI3K and MAPK pathways supports glioma cell proliferation. Oncogenesis, 3, e108.
35.
OstromQ.T., KinnersleyB., WrenschM.R., Eckel-PassowJ.E., ArmstrongG., RiceT., ChenY., WienckeJ.K., McCoyL.S., HansenH.M., AmosC.I., BernsteinJ.L., ClausE.B., Il'yasovaD., JohansenC., LachanceD.H., LaiR.K., MerrellR.T., OlsonS.H., SadetzkiS., SchildkrautJ.M., SheteS., RubinJ.B., LathiaJ.D., BerensM.E., AnderssonU., RajaramanP., ChanockS.J., LinetM.S., WangZ., YeagerM., GliomaScan, c., HoulstonR.S., JenkinsR.B., MelinB., BondyM.L., and Barnholtz-SloanJ.S. (2018). Sex-specific glioma genome-wide association study identifies new risk locus at 3p21.31 in females, and finds sex-differences in risk at 8q24.21. Sci. Rep. 8, 7352.
36.
WeiM.H., LatifF., BaderS., KashubaV., ChenJ.Y., DuhF.M., SekidoY., LeeC.C., GeilL., KuzminI., ZabarovskyE., KleinG., ZbarB., MinnaJ.D., and LermanM.I. (1996). Construction of a 600-kilobase cosmid clone contig and generation of a transcriptional map surrounding the lung cancer tumor suppressor gene (TSG) locus on human chromosome 3p21.3: progress toward the isolation of a lung cancer TSG. Cancer Res. 56, 1487–1492.
37.
TimmerT., TerpstraP., van den BergA., VeldhuisP.M., Ter ElstA., VoutsinasG., HulsbeekM.M., DraaijersT.G., LoomanM.W., KokK., NaylorS.L., and BuysC.H. (1999). A comparison of genomic structures and expression patterns of two closely related flanking genes in a critical lung cancer region at 3p21.3. Eur. J. Hum. Genet. 7, 478–486.
38.
ForniP.E., ScuoppoC., ImayoshiI., TaulliR., DastruW., SalaV., BetzU.A., MuzziP., MartinuzziD., VercelliA.E., KageyamaR., and PonzettoC. (2006). High levels of Cre expression in neuronal progenitors cause defects in brain development leading to microencephaly and hydrocephaly. J. Neurosci. 26, 9593–9602.
39.
JamsaiD., WatkinsD.N., O'ConnorA.E., MerrinerD.J., GursoyS., BirdA.D., KumarB., MillerA., ColeT.J., JenkinsB.J., and O'BryanM.K. (2017). In vivo evidence that RBM5 is a tumour suppressor in the lung. Sci. Rep. 7, 16323.
40.
ClarkR.S., KochanekP.M., DixonC.E., ChenM., MarionD.W., HeinemanS., DeKoskyS.T., and GrahamS.H. (1997). Early neuropathologic effects of mild or moderate hypoxemia after controlled cortical impact injury in rats. J. Neurotrauma, 14, 179–189.
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
