A Mouse PRMT1 Null Allele Defines an Essential Role for Arginine Methylation in Genome Maintenance and Cell Proliferation
Authors: Josée Hébert
Zhenbao Yu
En Li
Taiping Chen
Stéphane Richard
Journal: Molecular and Cellular Biology (2009)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: PRMT1; arginine methylation; embryonic lethality; DNA damage; cell cycle progression
Affiliations: Bloomfield Center for Research on Aging, Segal Cancer Centre, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Montréal, Québec, Canada., Epigenetics Program, Novartis Institutes for Biomedical Research, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, Leukemia Cell Bank of Quebec and Division of Hematology, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada, and Department of Medicine, Université de Montréal, Montreal, Quebec H3C 3J7, Canada, Terry Fox Molecular Oncology Group and Bloomfield Center for Research on Aging, Segal Cancer Centre, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, and Departments of Oncology and Medicine, McGill University, Montréal, Québec H3T 1E2, Canada

Abstract:  Protein arginine methyltransferase 1 (PRMT1) is the major enzyme that generates monomethylarginine and asymmetrical dimethylarginine. We report here a conditional null allele of PRMT1 in mice and that the loss of PRMT1 expression leads to embryonic lethality. Using the Cre/lox-conditional system, we show that the loss of PRMT1 in mouse embryonic fibroblasts (MEFs) leads to the loss of arginine methylation of substrates harboring a glycine-arginine rich motif, including Sam68 and MRE11. The loss of PRMT1 in MEFs leads to spontaneous DNA damage, cell cycle progression delay, checkpoint defects, aneuploidy, and polyploidy. We show using a 4-hydroxytamoxifen-inducible Cre that the loss of PRMT1 in MEFs leads to a higher incidence of chromosome losses, gains, structural rearrangements, and polyploidy, as documented by spectral karyotyping. Using PRMT1 small interfering RNA in U2OS cells, we further show that PRMT1-deficient cells are hypersensitive to the DNA damaging agent etoposide and exhibit a defect in the recruitment of the homologous recombination RAD51 recombinase to DNA damage foci. Taken together, these data show that PRMT1 is required for genome integrity and cell proliferation. Our findings also suggest that arginine methylation by PRMT1 is a key posttranslational modification in the DNA damage response pathway in proliferating mammalian cells. 

Retracted: No

PubPeer comments:
 Figure 6 appears to have some image duplications ![file]  Figure 6 - The fluorescent micrographs (magnification u00d7400) of MKN-45 human gastric cancer cells double-stained with acridine orange and propidium iodide. Untreated cells (A) reveal normal cell morphology without any signs of apoptosis while (B, 5 u00b5M) shows signs of early apoptosis, (C, 50 u00b5M) shows nuclear margination and blebbing and (D, 100 u00b5M) shows signs of late apoptosis. , 
 Fig 5.  Morphological features of apoptosis including chromatin condensation induced by 3-u03b2-erythrodiol (0 u00b5M, A), (5 u00b5M, B), (50 u00b5M, C), (100 u00b5M, D) for 48 h. (A) represents untreated control group which does not show any changes in cellular morphology. ![file] There s a lot going on. , 
 *[right]* Figure 4 from [Liu et al (2016)] .  Morphological changes of the cells after treatment with 3-u03b2-erythrodiol (magnification x200) detected by phase contrast microscopy. Cellular shrinkage was observed in 3-u03b2-erythrodiol-treated cells (black arrows). (A) Control (untreated cells), (B-D) effect of 5, 50 and 100 u03bcM of 3-u03b2-erythrodiol on cell morphology of MKN-45 cells. The number of cells with shrinkage increased with the increasing dose of the compound. *[left]* Figure 3 from [Wan et al (2016)] .  EEPC inhibited the growth of MG63 osteosarcoma cancer cells as shown by inverted light microscopy. Morphological changes of the cells after treatment with EEPC (magnification, x200). Cellular shrinkage was observed in EEPCu2011treated cells (arrows). MG63 cells were treated with (A) 0 u00b5g ml (control), (B) 40 u00b5g ml, (C) 80 u00b5g ml and (D) 150 u00b5g ml EEPC extract. The number of cells with shrinkage increased with an increase in the dose of the extract . ![file] , 
 #2 *[right]* Fig 5 from [Liu et al (2016)] .  Morphological features of apoptosis including chromatin condensation induced by 3-u03b2-erythrodiol (0 u00b5M, A), (5 u00b5M, B), (50 u00b5M, C), (100 u00b5M, D) for 48 h. (A) represents untreated control group which does not show any changes in cellular morphology. With annotations. *[left]* Figure 5 from [Li Wang (2016)] .  Morphological features of apoptosis including chromatin condensation induced by the combination of bornyl acetate (48 u00b5M, B), 5-FU (1.5 u00b5m, C) or their combination bornyl acetate (48 u00b5M) + 5-FU (1.5 u00b5M) (D) for 48 hrs. A represents the untreated control group. White arrows represent morphological changes in the gastric cancer cells. Combination treatment achieved the maximal damage . ![file] , 
 #1 *[left]* Fig 6 again. *[right]* Figure 3 from [Tian et al (2016)] .  Fluorescence microscopic images of OVCAR-3 cancer cells after treatment with 0 (A), 20 (B), 40 (C) and 100 (D) u00b5M dose of gentiopicroside for 48 h. The cells were double-stained with acridine orange and propidium iodide fluorescent dyes. Untreated cells (A) showed normal morphology (green colour) while as treated cells showed signs of moderate and extensive apoptosis at lower and higher doses respectively . ![file] The same graphic motifs appear in both, differently arranged. The Tian paper appeared in an Allied Academies journal ( Biomedical Research ), i.e. a polyp of the predatory publisher OMICS. No DOI or PMID, ruling out its own PubPeer thread. It was  Accepted January 30, 2016 (no submission or publication dates). The present paper was  Received October 30, 2015; Accepted December 11, 2015 , with a publication date of Feb 2016. Thus it appears that the two were prepared independently. , 
 Retracted [18 February 2021] .  Following the publication of the above paper, an interested reader drew to our attention that a number of apparent anomalies existed with the data presented in the above paper; specifically, there appeared to be strikingly similar and replicated patternings of the cells within the cellular images featured in Figs. 4A-D and 5A-D (affecting all the figure parts). Secondly, Fig. 4 in the above study appeared to have been a reproduction of Fig. 3 from following paper featuring different authors, albeit Fig. 4 appeared in greyscale, and not in colour, in the above paper [Wan G, Tao J-G, Wang G-D, Liu. S-P, Zhao H-X and Liang Q-D: In vitro antitumor activity of the ethyl acetate extract of* Potentilla chinensis* in osteosarcoma cancer cells. Mol Med Rep 14: 3634-3640, 2016].  Following an internal enquiry, the Editor of *Oncology Reports* was able to verify the claims made by the interested reader; therefore, in view of the number of potential anomalies that have been identified and owing to a lack of overall confidence in the presented data, the Editorial Board have decided to retract the above paper from the publication. The Journal were also contacted independently by the authors, who wished to retract the paper on account of not being able to reproduce the results shown in Fig.. 2. The Editor apologizes to the readership of the Journal for any inconvenience caused. ,