Endogenous p53 expression in human and mouse is not regulated by its 3′UTR

  1. Sibylle Mitschka
  2. Christine Mayr  Is a corresponding author
  1. Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, United States
7 figures, 2 tables and 2 additional files

Figures

Figure 1 with 1 supplement
Deletion of the endogenous 3′UTR does not alter TP53 mRNA level in human cells.

(A) Schematic of the human TP53 gene. The sequence deleted in dUTR cells is shown in blue. Tracks of binding sites for miRNAs, RNA-binding proteins, and lncRNAs are depicted below (see also Table 1). URE, U-rich element. CRISPR/Cas9-mediated deletions at the nucleotide level are shown in Figure 1—figure supplement 1. (B) Northern blot analysis of TP53 mRNA from WT and dUTR HEK293 cells. A probe that hybridizes to the TP53 coding region (CDS) reveals expression of a shortened TP53 mRNA in dUTR cells. The size difference is consistent with the length of the CRISPR/Cas9-induced deletion. A probe designed to bind the TP53 3′UTR does not produce a signal in the mRNA of dUTR cells, confirming deletion of this sequence element. The band of 18S rRNA is used as a loading control. * indicates an unspecific band originating from ribosomal RNA. (C) TP53 mRNA expression measured by RT-qPCR with a primer pair located in the 3′UTR in the indicated samples derived from HCT116 cells. KO, HCT116 TP53-/- cells. Data are shown as mean +s.d. of n = 5 independent experiments after normalization to GAPDH. Statistical analysis using ANOVA and Tukey’s post-hoc test with ***p<0.001, ns, not significant. (D) TP53 mRNA expression measured by RT-qPCR with a primer pair located in the CDS in the indicated samples derived from HCT116 cells. Data are shown as mean +s.d. of n = 5 independent experiments after normalization to GAPDH. Statistical analysis using ANOVA and Tukey’s post-hoc test with ***p<0.001, ns, not significant. (E) Experimental setup to estimate TP53 mRNA half-life. Metabolic labeling with 4-thiouridine (4sU) was used to enrich newly transcribed mRNAs. The newly transcribed RNAs were thiol-alkylated and biotinylated, followed by Streptavidin pull-down. Their relative abundance was measured using RT-qPCR. (F) TP53 mRNA half-life obtained by 4sU labeling as described in (E) is shown for the indicated samples derived from HCT116 cells in the presence or absence of etoposide for 4 hr (Eto, 20 µM). Shown is mean + s.d. from n = 3 independent experiments. Statistical analysis using ANOVA and Tukey’s post-hoc test with *p<0.05, **p<0.01, ns, not significant.

Figure 1—figure supplement 1
Generation and characterization of TP53 dUTR human cell lines.

(A) Sequence alignment of TP53 alleles spanning the deletion sites in WT and dUTR HEK293 and HCT116 cell clones analyzed in this study. Binding sites of gRNAs used to generate the deletion are underlined in the WT reference sequence and predicted cutting sites are marked by a scissor symbol. gRNA dUTR2.2 harboring a specific point mutation relative to the WT allele was used to create homozygous dUTR HCT116 cell lines during a second round of transfection. (B) TP53 mRNA expression was measured by RT-qPCR with a primer pair located in the CDS in the indicated samples derived from HEK293 cells. Shown is mean +s.d. of n = 7 independent experiments after normalization to GAPDH. Statistical analysis using ANOVA and Tukey’s post-hoc test with ***p<0.001; ns, not significant. (C) Immunoblot showing p53 protein level in HEK293 cells, grown under steady-state conditions. (D) Quantification of immunoblot data for steady-state p53 protein level in cells derived from HEK293. Shown is mean +s.d. of n = 4 independent experiments after normalization to Actin and the WT parental cell line. Statistical analysis using ANOVA and Tukey’s post-hoc test with ***p<0.001; ns, not significant.

Figure 2 with 1 supplement
Deletion of the endogenous TP53 3′UTR does not alter p53 protein level in steady state or after genotoxic stress.

(A) Representative immunoblot showing steady-state p53 protein expression in the indicated samples derived from HCT116 cells. Actin serves as loading control. See Figure 2—figure supplement 1 for additional information on p53 isoform expression. (B) Quantification of immunoblot data for steady-state p53 protein level. p53 expression data were normalized to Actin and the WT parental cell line. For each sample at least five biological replicates were measured. Statistical analysis using ANOVA. ns, not significant. (C) Representative immunoblots showing p53 protein levels after 4 hr of etoposide (Eto) treatment (0–32 µM) in WT, Ctrl clone #1, and dUTR clone #1 derived from HCT116 cells. Actin serves as loading control. (D) As in (C). Quantification of p53 protein expression from n = 4 independent experiments is shown as mean + s.d. Statistical analysis of cell line effect using ANOVA. ns, not significant. See Figure 2—source data 1 for raw data. (E) Representative immunoblot of samples from WT parental, Ctrl clone #1, and dUTR clone #1 derived from HCT116 cells that were treated with 0.5 µM Eto for 0, 24, or 48 hr (h). Actin serves as loading control. (F) As in (E). Quantification of p53 protein expression from n = 3 biological replicates is shown as mean +s.d. Statistical analysis of cell line effect using ANOVA. ns, not significant. See Figure 2—source data 1 for raw data. (G) As in (C), but cells were treated with 20 µM etoposide (Eto), 40 µM 5-fluorouridine (5-FU), or 50 J/m2 UV. Actin serves as loading control. (H) As in (G). Quantification of p53 protein expression after drug treatment. For each drug at least three biological replicates were measured. Shown is mean + s.d. Statistical analysis using ANOVA. ns, not significant.

Figure 2—figure supplement 1
Analysis of p53 protein isoform expression in TP53 dUTR HCT116 cells.

(A) Domain architecture of full-length (FL) p53 and all described alternative p53 protein isoforms. The respective binding epitopes of two antibodies used for isoform expression analysis, shown in (B) are highlighted in red. TAD, transactivation domain; PRD, proline-rich domain; DBD, DNA-binding domain; HR, hinge region; OD, oligomerization domain; RD, regulatory domain. The figure was adapted from Figure 3 from Joruiz and Bourdon, 2016. (B) Western blot analysis of p53 isoform expression pattern in HCT116 cell lines using two different monoclonal p53 antibodies. Increased expression of FL p53 protein was observed in samples treated with 20 µM Nutlin-3 (N) for 4 hr.

The endogenous TP53 3′UTR does not impact p53 protein synthesis and turnover.

(A) Immunoblot showing p53 protein levels after 4 hr of Nutlin-3 treatment (0–20 µM) in WT, Ctrl clone #1, and dUTR clone #1 derived from HCT116 cells. Actin serves as loading control. (B) As in (A). Quantification of p53 protein expression from n = 4 biological replicates is shown as mean +s.d. Statistical analysis of cell line effect using ANOVA. ns, not significant. See Figure 3—source data 1 for raw data. (C) Experimental setup to analyze p53 protein synthesis by metabolic labeling of proteins using the methionine analog azidohomoalanine (AHA) in the presence or absence of 20 µM etoposide. (D) Representative immunoblot for p53 synthesis assessed by metabolic labeling as shown in (C). The black triangle indicates the signal specific to p53 protein. (E) As in (D). Quantification of newly synthesized p53 protein using AHA-labeling for 2 hr. At least three biological replicates were measured in the presence or absence of 20 µM etoposide. Shown is mean +s.d. Statistical analysis using ANOVA. ns, not significant.

Figure 4 with 1 supplement
The p53 coding region has a dominant repressive effect on the expression of a reporter gene that overrides the contribution of the 3′UTR.

(A) FACS gating strategy to measure GFP protein expression in TP53-/- HCT116 cells. Live cells and single cells were used for downstream analysis. (B) Histogram plots from a representative FACS experiment. The gray area represents the untransfected, GFP-negative control population. Shown is GFP fluorescence intensity. (C) GFP protein levels were measured as mean fluorescence intensity (MFI) by FACS and GFP mRNA levels were measured by RT-qPCR using GAPDH as housekeeping gene in TP53-/- HCT116 cells. Shown is mean + s.d. of at least n = 3 independent experiments. CDS, coding sequence. Statistical analysis using ANOVA and Tukey’s post-hoc test with *p<0.05, **p<0.01, ***p<0.0001; ns, not significant. See Figure 4—figure supplement 1 for additional information.

Figure 4—figure supplement 1
Validation of repressive effects of the TP53 3′UTR in luciferase reporter assays.

(A) Renilla luciferase activity after expression of the indicated constructs containing either the human dUTR fragment or full-length 3′UTR in TP53-/- HCT116 cells. Shown is mean + s.d. of n = 3 independent experiments after normalization to firefly luciferase. (B) As in Figure 4C, but shown are additional constructs. GFP protein levels were quantified by FACS and GFP mRNA levels were measured by RT-qPCR using GAPDH as housekeeping gene in TP53-/- HCT116 cells. Shown is mean + s.d. of at least n = 4 independent experiments. CDS, coding sequence. Statistical analysis using ANOVA and Tukey’s post-hoc test with *p<0.05, **p<0.01, ***p<0.0001; ns, not significant.

Figure 5 with 2 supplements
Knockout of the Trp53 3′UTR does not induce aberrant p53 expression in a mouse model.

(A) Schematic of the murine Trp53 gene. The sequence deleted in dUTR cells is shown in blue. (B), Trp53 mRNA in tissues from WT and dUTR mice was normalized to Gapdh. Shown is mean + s.d. from n = 3 independent experiments. Statistical analysis using ANOVA. ns, not significant. CRISPR/Cas9-mediated deletions at the nucleotide level are shown in Figure 5—figure supplement 1C. (C) Representative immunoblots of p53 protein from tissues obtained 4 hr after total body irradiation. Gy, Gray. Tubulin or Actin serve as loading controls. Quantification of p53 protein expression values obtained from n = 3 mice is shown in Figure 5—figure supplement 2. (D) Cdkn1a mRNA expression of samples from (C) was normalized to Gapdh. Shown is mean + s.d. from three mice. Statistical analysis using ANOVA. ns, not significant.

Figure 5—figure supplement 1
Generation and characterization of Trp53 dUTR mice.

(A) Schematic of the mouse Trp53 gene. The sequence deleted in dUTR cells is shown in blue and binding sites of primers used for PCR screening are marked with arrows. (B) Screening-PCR of mice that were born after zygotic injection of CRISPR/Cas9 RNPs targeting the Trp53 3′UTR. The predicted lengths of the PCR products from WT and dUTR alleles are indicated. Mice that were selected for validation by sequencing are labeled in red. (C) Sequence alignments of Trp53 dUTR alleles of founder select mice shown in (B). Male mice #3 and #26 harboring identical DNA deletions were used to establish a mouse colony. Primer sequences used for screening can be found in Supplementary file 1. (D) Genotypes of pups from 28 Trp53 dUTR heterozygous intercrosses. Unknown refers to mice that died before weening. (E) Weights of mice at 10–11 weeks of age are shown for WT, Trp53 dUTR heterozygous and homozygous males. Data are shown as mean +s.d. with n = 6 in each group. Statistical analysis using ANOVA. ns, not significant.

Figure 5—figure supplement 2
p53 protein expression in tissues of WT and Trp53 dUTR mice after whole body irradiation.

Quantification p53 protein expression levels from immunoblot data in the indicated tissues. Tissue samples were analyzed 4 hr after total body irradiation as shown in Figure 5C. p53 expression levels were normalized to Actin or Tubulin, respectively and normalized to the maximum value within each data set. Data are shown as mean +s.d. from three mice. Gy, Gray. Statistical analysis using ANOVA. ns, not significant.

Author response image 1
mRNA cleavage and polyadenylation requires multiple sequence elements surrounding the cleavage site.

A, Schematic of the multiprotein complex responsible for mRNA cleavage and polyadenylation in humans. B, Sequence context of functional poly(A) sites showing the poly(A) signal hexamer as well as two common auxiliary motifs. The metaplot is aligned to the transcript end in the longest isoform of RefSeq-annotated human genes. C-E, Metagene analysis shows densities of the binding sites of protein components of the cleavage and polyadenylation machinery determined by CLIP: C, Cleavage Factor I complex D, Cleavage and Polyadenylation Specificity Factor complex and E, Cleavage Stimulation Factor complex. Binding sites were retrieved from the POSTAR2 database and aligned to RefSeq (Y. Zhu et al., 2019).

Author response image 2

Tables

Table 1
Previously reported evidence of miRNAs, lncRNAs, and RNA-binding proteins that target the TP53 3′UTR.
Interactors of the human TP53 mRNA mapping to the last exon
NameTypeBinding region (NM_000546.6)Affected in dUTR allele?ExperimentsReferences (PMID)Average
PhyloP score
miR-1228–3 pmiRNA1422–1428yesLRA, RT-qPCR, IHC, WB254229131.003
miR-125a-5pmiRNA2044–2063yesLRA, NB, RT-qPCR, WB19818772−0.120
miR-125b-5pmiRNA2043–2064yesLRA, ISH, RT-qPCR, WB19293287,
21935352,
27592685
−0.105
miR-1285–3 pmiRNA2113–2134yesLRA, RT-qPCR, WB20417621−0.061
miR-150–5 pmiRNA1568–1580yesLRA, WB23747308−0.323
miR-151a-5pmiRNA2304–2325yesLRA, ChIP-seq, RT-qPCR, WB27191259−0.053
miR-200a-3pmiRNA2269–2291yesLRA, WB23144891−0.039
miR-24–3 pmiRNA2352–2374yesLRA, IHC, RT-qPCR, WB277801400.018
miR-25–3 pmiRNA1401–1423yesLRA, RT-qPCR, WB209356780.438
miR-30d-5pmiRNA1596–1618yesLRA, RT-qPCR, WB20935678−0.432
miR-375miRNA1462–1483yesLRA, Flow, RT-qPCR, WB, IF23835407−0.595
miR-663amiRNA1260–1281no (in CDS)LRA271055171.520
miR-504miRNA2059–2066,
2387–2395
yes, noLRA, RT-qPCR, WB205420010.130
0.203
miR-92miRNA1417–1422yesLRA, WB211125620.102
miR-141miRNA2285–2290yesLRA, WB21112562−0.031
miR-638miRNA1381–1404yesLRA, WB, IP250884220.313
miR-3151miRNA1337–1354yesLRA, WB, RT-qPCR24736457−0.329
miR-33miRNA1957–1980yesLRA, WB207030860.138
miR-380–5 pmiRNA1909–1936,
1943–1974
yes, yesLRA, WB208716090.121
0.089
miR-19bmiRNA1712–1734yesLRA, WB247429360.402
miR-15amiRNA2394–2414noLRA, WB212059670.045
miR-16miRNA2394–2415noLRA, WB212059670.015
miR-584miRNA1263–1284no (in CDS)LRA, WB, IP250884221.646
WIG1RBP2064–2106yesLRA, IP, RT-qPCR19805223−0.071
PARNRBP2071–2102yesLRA, EMSA, IP, RT-qPCR23401530−0.097
CPEB1RBP2458–2500noIP, RT-PCR191414771.654
RBM38
(RNPC1)
RBP2064–2106yesEMSA, IP, RT-PCR,
Polysome gradient
21764855,
24142875,
25823026
−0.071
RBM24RBP2064–2106yesLRA, EMSA, IP, RT-qPCR,29358667−0.071
HURRBP2064–2106,
2393–2412,
2458–2505
yes, yes, noLRA, EMSA, WB, RT-qPCR12821781,
14517280,
16690610,
18680106
−0.071
0.007
1.496
7SLlncRNA2107–2149,
2194–2240,
2269–2301,
2307–2362
yes, yes, yes, yesLRA, IP, WB25123665−0.158
−0.110
0.015
−0.015
miR-92a-3pmiRNA1646–1666yesLRA, WB22451425−0.122
TIA1RBP1426–1442
1702–1731
yes, noLRA, iCLIP289043500.066
0.715
HzfRBP1345–1395
1529–1574
yes, yesLRA, EMSA, WB, IP,
RT-qPCR, Polysome gradient
21402775−0.450
0.156
  1. LRA: luciferase reporter assay; WB: western blot; IP: co-immunoprecipitation assay; RT-qPCR: quantitative reverse transcription PCR; NB: northern blot; IHC: immunohistochemistry; ISH: In situ hybridization; EMSA: electromobility shift assay.

Key resources table
Reagent type (species) or resourceDesignationSource or referenceIdentifiersAdditional information
Strain, strain background (Mus musculus)C57Bl/6JJackson Laboratory#000664
RRID:IMSR_JAX:000664
used to generate TP53 dUTR mouse strain
Strain, strain background (Mus musculus)Trp53 dUTRThis paperC57Bl/6J background, see Materials and methods Supplementary file 1
Cell line (Homo sapiens)FLP In T-REx 293From Dr. Thomas Tuschl (Rockefeller University)RRID:CVCL_U427
Cell line (Homo sapiens)FLP In T-REx 293 TP53 dUTRThis papersee Materials and methods Supplementary file 1
Cell line (Homo sapiens)FLP In T-REx 293 TP53-/-This papersee Materials and methods Supplementary file 1
Cell line (Homo sapiens)HCT116ATCCATCC CCL-247
RRID:CVCL_0291
Cell line (Homo sapiens)HCT116 Ctrl (two clones)This papersee Materials and methods Supplementary file 1
Cell line (Homo sapiens)HCT116 TP53 dUTR (three clones)This papersee Materials and methods Supplementary file 1
Cell line (Homo sapiens)HCT116 TP53-/-This papersee Materials and methods Supplementary file 1
Peptide, recombinant proteinCas9 protein with NLSPNA BioCP01-20
Sequence-based reagentCostum Alt-R CRISPR Cas9 crRNA (Trp53_gRNA upstream)IDTGTGATGGGGACGGGATGCAGused for CRISPR RNP formation
Sequence-based reagentCostum Alt-R CRISPR Cas9crRNA (Trp53_gRNA downstream)IDTCATAGGGTCCATATC CTCCAused for CRISPR RNP formation
Sequence-based reagentAlt-R CRISPR-Cas9 tracrRNAIDT1072532
AntibodyAnti-p53 clone DO-7 (mouse monoclonal)Santa Cruzsc-47698
RRID:AB_628083
(1:250)
AntibodyAnti-p53 clone PAb240 (mouse monoclonal)Santa Cruzsc-99
RRID:AB_628086
(1:250)
AntibodyAnti-p53 clone 1C12 (mouse monoclonal)Cell Signaling#2524
RRID:AB_331743
(1:500)
AntibodyAnti-Actin (rabbit polyclonal)SigmaA2066
RRID:AB_476693
(1:1,000)
AntibodyAnti-Tubulin (mouse monoclonal)SigmaT9026
RRID:AB_477593
(1:1,000)
AntibodyIRDye 800CW anti-Mouse (goat polyclonal)LI-COR926–32210
RRID:AB_621842
(1:10,000)
AntibodyIRDye 680RD anti-Rabbit (goat polyclonal)LI-COR926–68071
RRID:AB_10956166
(1:10,000)
Transfected construct (synthetic)pX330-U6-Chimeric_BB-CBh-hSpCas9AddgeneRRID:Addgene_42230
Transfected construct (Homo sapiens)pX330-gRNA dUTR1This papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pX330-gRNA dUTR2.1This papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pX330-gRNA dUTR2.2This papersee Materials and methods Supplementary file 1
Transfected construct (synthetic)pCDNA3-puro eGFPPMID:30449617
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFPThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro eGFP_TP53-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFP_TP53-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro eGFP_dUTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFP_dUTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro eGFP_TP53-3UTR(U-del)This papersee Materials and methods
Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFP_TP53-3UTR(U-del)This papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro eGFP_GAPDH-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFP_GAPDH-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro eGFP_HPRT-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFP_HPRT-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro eGFP_PGK1-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro p53(CDS)-eGFP_PGK1-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro 5UTR_p53(CDS)-eGFPThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro 5UTR_p53(CDS)-eGFP_dUTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)pCDNA3-puro 5UTR_p53(CDS)-eGFP_TP53-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (synthetic)psiCHECK-2PromegaC8021
Transfected construct (Homo sapiens)psiCHECK-2_TP53-3UTRThis papersee Materials and methods Supplementary file 1
Transfected construct (Homo sapiens)psiCHECK-2_dUTRThis papersee Materials and methods Supplementary file 1
Chemical compound, drugIRDye 680LT StreptavidinLI-COR926–68031(1:2,000)
Chemical compound, drugNutlin-3SeleckchemS1061
Chemical compound, drugEtoposideSigma341205–25 MG
Chemical compound, drug5-FluorouracilSigmaF6627
Chemical compound, drugMTSEA-biotin-XXBiotium900661
Chemical compound, drugBiotin Alkyne (PEG4 carboxamide-Propargyl Biotin)This paperB10185
Chemical compound, drug4-ThiouridineMP BiomedicalsMP215213425
Chemical compound, drugYeast tRNAInvitrogen15401029
Chemical compound, drugdCTP [α−32P]Perkin ElmerNEG013H100UC
Commercial assay or kitClick-iT Protein Reaction Buffer KitInvitrogenC10276
Commercial assay or kitClick-iT AHA (L-Azidohomoalanine)InvitrogenC10102
Commercial assay or kitSuperScript IV Vilo Master MixInvitrogen11756050
Commercial assay or kitDual-Glo Luciferase Assay SystemPromegaE2940
Commercial assay or kitMegaprime DNA labeling system, dCTPCytivaRPN1606
Commercial assay or kitLipofectmaine LTX Reagent with PLUS ReagentInvitrogenA12621
Commercial assay or kitDynabeads Protein G for ImmunoprecipitationInvitrogen10004D
Commercial assay or kitDynabeads MyOne Streptavidin C1Invitrogen65001
Commercial assay or kitOligotex mRNA mini KitQuiagen70022
Commercial assay or kitULTRAhyb Ultrasensistive Hybridization bufferInvitrogenAM8670
Commercial assay or kitQuickExtract DNA Extraction SolutionLucigenQE09050
Commercial assay or kitRNAlater-ICE Frozen Tissue Transition SolutionInvitrogenAM7030
Commercial assay or kitSuperScript IV VILO Master Mix with ezDNAse EnzymeInvitrogen11766050
Commercial assay or kitFastStart Universal SYBR Green Master (ROX)Roche/Sigma4913850001
Software, algorithmFlowJo (Version 10.5.3)FlowJo, LLC
Software, algorithmPrism 8 for OS X (Version 8.4.3)Graph Pad Software, LLC
Software, algorithmImage Studio (Version 5.2)LI-COR Biosciences

Additional files

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Sibylle Mitschka
  2. Christine Mayr
(2021)
Endogenous p53 expression in human and mouse is not regulated by its 3′UTR
eLife 10:e65700.
https://doi.org/10.7554/eLife.65700