Build A Braveheart: The Missing Linc (RNA)
2013; Lippincott Williams & Wilkins; Volume: 112; Issue: 12 Linguagem: Inglês
10.1161/circresaha.113.301519
ISSN1524-4571
AutoresMasaharu Kataoka, Zhan‐Peng Huang, Da‐Zhi Wang,
Tópico(s)Cancer-related gene regulation
ResumoHomeCirculation ResearchVol. 112, No. 12Build A Braveheart: The Missing Linc (RNA) Free AccessResearch ArticlePDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessResearch ArticlePDF/EPUBBuild A Braveheart: The Missing Linc (RNA) Masaharu Kataoka, Zhan-Peng Huang and Da-Zhi Wang Masaharu KataokaMasaharu Kataoka From the Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA. , Zhan-Peng HuangZhan-Peng Huang From the Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA. and Da-Zhi WangDa-Zhi Wang From the Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA. Originally published7 Jun 2013https://doi.org/10.1161/CIRCRESAHA.113.301519Circulation Research. 2013;112:1532–1534Braveheart, A Long Noncoding RNA Required for Cardiovascular Lineage CommitmentKlattenhoff et alCell. 2013;152:570–583.A novel long noncoding RNA (lncRNA), Braveheart (Bvht), has been defined as a critical regulator of commitment of the embryonic stem cells (ESCs) to cardiovascular lineages. Bvht activates a cardiovascular gene network and functions upstream of mesoderm posterior 1 (MESP1), a master regulator of a common multipotent cardiovascular progenitor. Bvht mediates epigenetic regulation of commitment to a cardiac lineage by interacting with suppressor of zeste12 (SUZ12), a component of polycomb repressive complex 2 (PRC2). Bvht represents the first lncRNA that defines cardiac cell fate and lineage specificity, linking lncRNAs to cardiac development and disease.One surprise of the human genome project was that only ≈20 000 to 25 000 protein-coding genes exist in our species.1 In fact, even the simple roundworm C. elegans has similar number of protein-coding genes. Astonishingly, only 98% of our genome for? Thanks to the innovations in sequencing technologies and new computational methods for transcriptome assembly. It is now recognized that the majority of the genome is actively transcribed to produce thousands of noncoding transcripts in many cell types and tissues.3–5 A subset of these noncoding transcripts are classified as lncRNAs, transcribed RNA molecules >200 nucleotides in length that do not encode proteins.4–6 Many of the lncRNAs are large intergenic noncoding RNAs (lincRNAs). The functions of lncRNAs have recently been investigated in diverse biological processes, such as stem cell pluripotency, immune responses, and cell-cycle regulation.7–9 lncRNAs have been reported to promote developmental transitions and function as key regulators of cell fate commitment.10 Moreover, lncRNAs were reported to interact with ESC gene regulatory networks, leading to the maintenance of ESCs and lineage-specific differentiation by regulating key transcription factors and pluripotency markers.11–13 One of the best studied examples of lncRNAs is X-inactive-specific transcript, which is involved in the process of genomic imprinting and X chromosome inactivation.14,15 X-inactive–specific transcript is transcribed from the inactive X chromosome and plays a key role in epigenetic gene silencing, primarily by recruiting PRC2 to the promoters/enhancers of target genes. Mechanistically, lncRNAs were shown to function either in cis or in trans to regulate gene expression locally or genome wide.15,16 However, little is known about the expression and functional significance of lncRNAs in the heart, in particular, during cardiac lineage commitment.In the January 31, 2013 issue of Cell, Klattenhoff et al17 identified a novel lncRNA, Bvht, in mouse heart and demonstrated that Bvht is a key regulator of cardiac lineage commitment and cardiac gene expression. Bvht was initially discovered from database mining aimed at identifying cardiac-expressed lncRNAs. Among 47 candidate lncRNAs identified, Bvht was highly expressed in the heart. Because most lncRNA genes share similar gene structure with protein-coding genes, such as promoter histone modifications, exons, introns, and polyadenylation sites,18 it is essential to first prove the noncoding status of a given lncRNA. Bvht encodes a transcript of ≈590 nucleotides that contain 2 short open reading frames with coding potential for peptides of 48 and 74 amino acids. Two lines of evidence indicate that these open reading frames do not produce detectable proteins. First, the authors found that ectopic transfection with a Bvht expression construct did not yield detectable protein product. Second, they showed that the putative open reading frames of the Bvht transcript associated poorly with ribosomes, indicating they are not actively translated. Together, these results strongly suggest that Bvht is a true lncRNA. To further bolster this point, the authors might assess the effect of Bvht frame-shift mutations on putative functions of the lncRNA.To study the biological function of Bvht, the investigators turned to in vitro differentiation of mouse ESCs. They knocked down Bvht by stably expressing short hairpin RNAs in ESCs. They found that Bvht was not required for global ESC differentiation nor was it required for ESC self-renewal. Instead, Bvht played a key role in cardiac commitment, promoting cardiac cell fate from nascent mesoderm. Similarly, the investigators showed that Bvht is necessary for the maintenance of cardiac fate in neonatal ventricular cardiomyocytes.The authors found that depletion of Bvht reduced formation of contracting cardiomyocytes during ESC differentiation. Bvht-depleted ESCs failed to activate the key cardiac transcription factors that govern cardiogenesis. To connect Bvht with the regulatory pathways for cardiomyocyte specification, the investigators performed unbiased genome-wide RNA-seq in Bvht-depleted ESCs. They found >548 genes were dysregulated when compared with that of control ESCs. Many of these altered genes are involved in transcriptional control of cardiac gene expression. In particular, MESP1, a key transcription factor for cardiac differentiation, was significantly downregulated in Bvht-depleted ESCs. MESP1 marks a multipotent cardiovascular progenitor, although MESP1 is not totally cardiovascular-specific.19–22 MESP1 expression, together with ETS2, was sufficient to transdifferentiate dermal fibroblasts into cardiac progenitors.23 Klattenhoff et al17 showed that Bvht regulates a core network of genes, including Mesp1, to drive cardiac differentiation. More specifically, they provided evidence that Bvht functions upstream of Mesp1 as a permissive factor for cardiac commitment during ESC differentiation. These findings place Bvht on the top of cardiac lineage commitment regulatory pyramid and suggest that it is among the earliest cardiac genes activated during development. Therefore, the discovery of Bvht represents a significant breakthrough that, for the first time, connects a lncRNA to cardiac specification. Together with recent reports demonstrating that dozens of lncRNAs block key lineage commitment programs within ESCs and function in crucial ESC regulatory pathways,12 it is evident that lncRNAs have emerged as a novel class of key regulators for cell fate determination.To define the molecular mechanisms by which Bvht works and more specifically to determine whether Bvht acts in cis or in trans, the investigators first examined the expression of Bvht neighboring genes in Bvht-depleted ESCs. They provided convincing evidence to suggest that Bvht did not alter the expression of its neighboring genes in cis. However, the authors observed that the expression of neighboring microRNA-143/145 genes was dramatically repressed in Bvht-depleted ESCs. This decrease was attributed to the loss of differentiating cardiomyocytes, rather than being directly related to Bvht depletion. Having ruled out cis-regulatory mechanisms, the investigators next tested whether Bvht functioned in trans. Given the previously reported interaction of lincRNAs with epigenetic regulators, such as PRC2,24 the authors looked for Bvht–PRC2 interaction. Indeed, they found that Bvht directly interacts with PRC2 through SUZ12 during cardiomyocyte differentiation. Furthermore, H3K27me3 levels paralleled SUZ12 enrichment, suggesting epigenetic regulation by Bvht.lncRNAs are emerging as an exciting area of investigation. However, there are more questions than answers about how they work. For example, how is the specificity of Bvht in epigenetic regulation during cardiovascular lineage commitment determined? How does Bvht–PRC2 interaction promote Mesp1 expression? Does Bvht epigenetically regulate the expression of a broad spectrum of targets or only a limited list of cardiac transcriptional factors? Recent studies showed that lncRNAs, such as RepA and Hotair, are required for the recruitment of PRC2 complex to a specific genomic locus and further execute its function in epigenetic regulation.25,26 It will be interesting to know whether Bvht will act in a similar manner. If so, to which chromatin locus does Bvht recruit PRC2? Furthermore, Bvht-regulated cardiac transcription factor genes presented in this study are located in multiple genomic loci, indicating that different molecular mechanisms may exist underlying Bvht-mediated epigenetic regulation.Genome-wide studies indicated that human lncRNAs are less conserved than protein-coding genes, and an estimated 30% of human lncRNAs are primate specific.18 Klattenhoff et al17 reported that Bvht seemed to exist as a mouse-specific lncRNA. Direct sequence alignment did not identify mouse Bvht homologs in other species. Moreover, by applying RNA-Seq approach, the authors nicely documented the expression of Bvht in mouse ESCs and heart samples. However, the orthologous human and rat genomic regions were not actively transcribed. Lack of an apparent human Bvht homolog raises a question about how well the lessons we have learned from mouse Bvht will translate to human cardiovascular disease. Perhaps, an undiscovered functional Bvht homolog, transcribed from a different genomic locus, exists in the human genome.In their study, the authors showed that Bvht transcript is expressed in several adult mouse tissues, such as brain, colon, heart, kidney, liver, muscle, spleen, and testes, with highest expression detected in the heart. It will be important to further characterize the spatiotemporal expression of Bvht in development and disease. Most importantly, it will be essential to define the in vivo function of Bvht in mice, using genetic loss-of-function approaches. Although Bvht was shown to be an important cardiac lncRNA, additional cardiac-expressed lncRNAs, in particular selectively expressed in cardiomyocytes, remain to be identified and studied. Cardiac transcription factors and miRNAs reprogram cardiac fibroblasts into cardiomyocytes in vitro and in vivo,27–30 raising the tantalizing possibility that reprogramming strategies may be used to enhance the limited native regenerative capacity of adult mammalian hearts.31,32 It will be interesting to study whether this lncRNA might also participate in cardiac regeneration or be used to stimulate cellular reprogramming to directly reprogram cardiac fibroblasts into cardiomyocytes. Clearly, the discovery of Bvht will significantly impact cardiovascular research field and link lncRNAs to human cardiovascular disease.AcknowledgmentsWe thank Dr William Pu for stimulating discussion and critical reading of this commentary.DisclosuresWork in Dr Wang's laboratory was supported by the March of Dimes Foundation and National Institutes of Health. Dr Kataoka was supported by Banyu Life Science Foundation International. Dr Huang is a postdoctoral fellow and Dr Wang is an Established Investigator of the American Heart Association.FootnotesThe opinions expressed in this Commentary are not necessarily those of the editors or of the American Heart Association.Commentaries serve as a forum in which experts highlight and discuss articles (published here and elsewhere) that the editors of Circulation Research feel are of particular significance to cardiovascular medicine.Commentaries are edited by Aruni Bhatnagar, University of Louisville.Correspondence to Da-Zhi Wang, PhD, Department of Cardiology, Boston Children's Hospital, Harvard Medical School, 320 Longwood Ave, Boston, MA 02115. E-mail [email protected]References1. International Human Genome Sequencing Consortium. Finishing the euchromatic sequence of the human genome.Nature. 2004; 431:931–945.CrossrefMedlineGoogle Scholar2. Elgar G, Vavouri T. Tuning in to the signals: noncoding sequence conservation in vertebrate genomes.Trends Genet. 2008; 24:344–352.CrossrefMedlineGoogle Scholar3. Mortazavi A, Williams BA, McCue K, Schaeffer L, Wold B. Mapping and quantifying mammalian transcriptomes by RNA-Seq.Nat Methods. 2008; 5:621–628.CrossrefMedlineGoogle Scholar4. Guttman M, Garber M, Levin JZ, Donaghey J, Robinson J, Adiconis X, Fan L, Koziol MJ, Gnirke A, Nusbaum C, Rinn JL, Lander ES, Regev A. Ab initio reconstruction of cell type-specific transcriptomes in mouse reveals the conserved multi-exonic structure of lincRNAs.Nat Biotechnol. 2010; 28:503–510.CrossrefMedlineGoogle Scholar5. Cabili MN, Trapnell C, Goff L, Koziol M, Tazon-Vega B, Regev A, Rinn JL. Integrative annotation of human large intergenic noncoding RNAs reveals global properties and specific subclasses.Genes Dev. 2011; 25:1915–1927.CrossrefMedlineGoogle Scholar6. Mercer TR, Dinger ME, Sunkin SM, Mehler MF, Mattick JS. Specific expression of long noncoding RNAs in the mouse brain.Proc Natl Acad Sci U S A. 2008; 105:716–721.CrossrefMedlineGoogle Scholar7. Guttman M, Amit I, Garber M, et al. Chromatin signature reveals over a thousand highly conserved large non-coding RNAs in mammals.Nature. 2009; 458:223–227.CrossrefMedlineGoogle Scholar8. Hung T, Wang Y, Lin MF, et al. Extensive and coordinated transcription of noncoding RNAs within cell-cycle promoters.Nat Genet. 2011; 43:621–629.CrossrefMedlineGoogle Scholar9. Ravasi T, Suzuki H, Pang KC, Katayama S, Furuno M, Okunishi R, Fukuda S, Ru K, Frith MC, Gongora MM, Grimmond SM, Hume DA, Hayashizaki Y, Mattick JS. Experimental validation of the regulated expression of large numbers of non-coding RNAs from the mouse genome.Genome Res. 2006; 16:11–19.CrossrefMedlineGoogle Scholar10. Pauli A, Rinn JL, Schier AF. Non-coding RNAs as regulators of embryogenesis.Nat Rev Genet. 2011; 12:136–149.CrossrefMedlineGoogle Scholar11. Guttman M, Donaghey J, Carey BW, et al. LincRNAs act in the circuitry controlling pluripotency and differentiation.Nature. 2011; 477:295–300.CrossrefMedlineGoogle Scholar12. Sheik Mohamed J, Gaughwin PM, Lim B, Robson P, Lipovich L. Conserved long noncoding RNAs transcriptionally regulated by Oct4 and Nanog modulate pluripotency in mouse embryonic stem cells.RNA. 2010; 16:324–337.CrossrefMedlineGoogle Scholar13. Dinger ME, Amaral PP, Mercer TR, Pang KC, Bruce SJ, Gardiner BB, Askarian-Amiri ME, Ru K, Soldà G, Simons C, Sunkin SM, Crowe ML, Grimmond SM, Perkins AC, Mattick JS. Long noncoding RNAs in mouse embryonic stem cell pluripotency and differentiation.Genome Res. 2008; 18:1433–1445.CrossrefMedlineGoogle Scholar14. Brown CJ, Ballabio A, Rupert JL, Lafreniere RG, Grompe M, Tonlorenzi R, Willard HF. A gene from the region of the human X inactivation centre is expressed exclusively from the inactive X chromosome.Nature. 1991; 349:38–44.CrossrefMedlineGoogle Scholar15. Lee JT. Epigenetic regulation by long noncoding RNAs.Science. 2012; 338:1435–1439.CrossrefMedlineGoogle Scholar16. Batista PJ, Chang HY. Long noncoding RNAs: cellular address codes in development and disease.Cell. 2013; 152:1298–1307.CrossrefMedlineGoogle Scholar17. Klattenhoff CA, Scheuermann JC, Surface LE, Bradley RK, Fields PA, Steinhauser ML, Ding H, Butty VL, Torrey L, Haas S, Abo R, Tabebordbar M, Lee RT, Burge CB, Boyer LA. Braveheart, a long noncoding RNA required for cardiovascular lineage commitment.Cell. 2013; 152:570–583.CrossrefMedlineGoogle Scholar18. Derrien T, Johnson R, Bussotti G, et al. The GENCODE v7 catalog of human long noncoding RNAs: analysis of their gene structure, evolution, and expression.Genome Res. 2012; 22:1775–1789.CrossrefMedlineGoogle Scholar19. Bondue A, Blanpain C. Mesp1: a key regulator of cardiovascular lineage commitment.Circ Res. 2010; 107:1414–1427.LinkGoogle Scholar20. Bondue A, Lapouge G, Paulissen C, Semeraro C, Iacovino M, Kyba M, Blanpain C. Mesp1 acts as a master regulator of multipotent cardiovascular progenitor specification.Cell Stem Cell. 2008; 3:69–84.CrossrefMedlineGoogle Scholar21. David R, Brenner C, Stieber J, Schwarz F, Brunner S, Vollmer M, Mentele E, Müller-Höcker J, Kitajima S, Lickert H, Rupp R, Franz WM. MesP1 drives vertebrate cardiovascular differentiation through Dkk-1-mediated blockade of Wnt-signalling.Nat Cell Biol. 2008; 10:338–345.CrossrefMedlineGoogle Scholar22. Lindsley RC, Gill JG, Murphy TL, Langer EM, Cai M, Mashayekhi M, Wang W, Niwa N, Nerbonne JM, Kyba M, Murphy KM. Mesp1 coordinately regulates cardiovascular fate restriction and epithelial-mesenchymal transition in differentiating ESCs.Cell Stem Cell. 2008; 3:55–68.CrossrefMedlineGoogle Scholar23. Islas JF, Liu Y, Weng KC, Robertson MJ, Zhang S, Prejusa A, Harger J, Tikhomirova D, Chopra M, Iyer D, Mercola M, Oshima RG, Willerson JT, Potaman VN, Schwartz RJ. Transcription factors ETS2 and MESP1 transdifferentiate human dermal fibroblasts into cardiac progenitors.Proc Natl Acad Sci U S A. 2012; 109:13016–13021.CrossrefMedlineGoogle Scholar24. Rinn JL, Chang HY. Genome regulation by long noncoding RNAs.Annu Rev Biochem. 2012; 81:145–166.CrossrefMedlineGoogle Scholar25. Zhao J, Sun BK, Erwin JA, Song JJ, Lee JT. Polycomb proteins targeted by a short repeat RNA to the mouse X chromosome.Science. 2008; 322:750–756.CrossrefMedlineGoogle Scholar26. Rinn JL, Kertesz M, Wang JK, Squazzo SL, Xu X, Brugmann SA, Goodnough LH, Helms JA, Farnham PJ, Segal E, Chang HY. Functional demarcation of active and silent chromatin domains in human HOX loci by noncoding RNAs.Cell. 2007; 129:1311–1323.CrossrefMedlineGoogle Scholar27. Ieda M, Fu JD, Delgado-Olguin P, Vedantham V, Hayashi Y, Bruneau BG, Srivastava D. Direct reprogramming of fibroblasts into functional cardiomyocytes by defined factors.Cell. 2010; 142:375–386.CrossrefMedlineGoogle Scholar28. Qian L, Huang Y, Spencer CI, Foley A, Vedantham V, Liu L, Conway SJ, Fu JD, Srivastava D. In vivo reprogramming of murine cardiac fibroblasts into induced cardiomyocytes.Nature. 2012; 485:593–598.CrossrefMedlineGoogle Scholar29. Song K, Nam YJ, Luo X, Qi X, Tan W, Huang GN, Acharya A, Smith CL, Tallquist MD, Neilson EG, Hill JA, Bassel-Duby R, Olson EN. Heart repair by reprogramming non-myocytes with cardiac transcription factors.Nature. 2012; 485:599–604.CrossrefMedlineGoogle Scholar30. Jayawardena TM, Egemnazarov B, Finch EA, Zhang L, Payne JA, Pandya K, Zhang Z, Rosenberg P, Mirotsou M, Dzau VJ. MicroRNA-mediated in vitro and in vivo direct reprogramming of cardiac fibroblasts to cardiomyocytes.Circ Res. 2012; 110:1465–1473.LinkGoogle Scholar31. Bergmann O, Bhardwaj RD, Bernard S, Zdunek S, Barnabé-Heider F, Walsh S, Zupicich J, Alkass K, Buchholz BA, Druid H, Jovinge S, Frisén J. Evidence for cardiomyocyte renewal in humans.Science. 2009; 324:98–102.CrossrefMedlineGoogle Scholar32. Hsieh PC, Segers VF, Davis ME, MacGillivray C, Gannon J, Molkentin JD, Robbins J, Lee RT. Evidence from a genetic fate-mapping study that stem cells refresh adult mammalian cardiomyocytes after injury.Nat Med. 2007; 13:970–974.CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetailsCited By López-Jiménez E and Andrés-León E (2021) The Implications of ncRNAs in the Development of Human Diseases, Non-Coding RNA, 10.3390/ncrna7010017, 7:1, (17) Pérez-Agustín A, Pinsach-Abuin M and Pagans S (2020) Role of Non-Coding Variants in Brugada Syndrome, International Journal of Molecular Sciences, 10.3390/ijms21228556, 21:22, (8556) Bektik E, Cowan D and Wang D (2020) Long Non-Coding RNAs in Atrial Fibrillation: Pluripotent Stem Cell-Derived Cardiomyocytes as a Model System, International Journal of Molecular Sciences, 10.3390/ijms21155424, 21:15, (5424) Li X, Aishan B, Yang Y, Xie Y, Lati D and Tuerxun P (2020) Chemokine (C-C motif) Ligand 6 Aggravates Hypoxia Reoxygenation–induced Apoptosis in H9c2 Cells Through Enhancing the Expression of Insulin-like Growth Factor 2-Antisense, Journal of Cardiovascular Pharmacology, 10.1097/FJC.0000000000000905, 76:5, (549-555) Zhu J, Wang Y, Yu W, Xia K, Huang Y, Wang J, Liu B, Tao H, Liang C and Li F Long Noncoding RNA: Function and Mechanism on Differentiation of Mesenchymal Stem Cells and Embryonic Stem Cells, Current Stem Cell Research & Therapy, 10.2174/1574888X14666181127145809, 14:3, (259-267) E S, Costa M, Kurc S, Drożdż A, Cortez-Dias N and Enguita F (2018) The circulating non-coding RNA landscape for biomarker research: lessons and prospects from cardiovascular diseases, Acta Pharmacologica Sinica, 10.1038/aps.2018.35, 39:7, (1085-1099), Online publication date: 1-Jul-2018. Han D, Gao Q and Cao F (2017) Long noncoding RNAs (LncRNAs) — The dawning of a new treatment for cardiac hypertrophy and heart failure, Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, 10.1016/j.bbadis.2017.02.024, 1863:8, (2078-2084), Online publication date: 1-Aug-2017. Huang Z, Ding Y, Chen J, Wu G, Kataoka M, Hu Y, Yang J, Liu J, Drakos S, Selzman C, Kyselovic J, Qu L, dos Remedios C, Pu W and Wang D (2016) Long non-coding RNAs link extracellular matrix gene expression to ischemic cardiomyopathy, Cardiovascular Research, 10.1093/cvr/cvw201, 112:2, (543-554), Online publication date: 1-Nov-2016. Naya F and Wang D (2016) (MYO)SLIDing Our Way Into the Vascular Pool of Long Noncoding RNAs, Arteriosclerosis, Thrombosis, and Vascular Biology, 36:10, (2033-2034), Online publication date: 1-Oct-2016.Marian A (2014) Recent Developments in Cardiovascular Genetics and Genomics, Circulation Research, 115:7, (e11-e17), Online publication date: 12-Sep-2014. Kataoka M and Wang D (2014) Non-Coding RNAs Including miRNAs and lncRNAs in Cardiovascular Biology and Disease, Cells, 10.3390/cells3030883, 3:3, (883-898) Matkovich S, Edwards J, Grossenheider T, de Guzman Strong C and Dorn G (2014) Epigenetic coordination of embryonic heart transcription by dynamically regulated long noncoding RNAs, Proceedings of the National Academy of Sciences, 10.1073/pnas.1410622111, 111:33, (12264-12269), Online publication date: 19-Aug-2014. Gao C and Wang Y (2014) Transcriptome Complexity in Cardiac Development and Diseases, Circulation Journal, 10.1253/circj.CJ-14-0412, 78:5, (1038-1047), . Gurha P and Marian A (2013) Noncoding RNAs in Cardiovascular Biology and Disease, Circulation Research, 113:12, (e115-e120), Online publication date: 6-Dec-2013. (2013) Recent Advances in Cardiovascular Development, Circulation Research, 113:11, (e102-e105), Online publication date: 8-Nov-2013. June 7, 2013Vol 112, Issue 12 Advertisement Article InformationMetrics © 2013 American Heart Association, Inc.https://doi.org/10.1161/CIRCRESAHA.113.301519PMID: 23743224 Originally publishedJune 7, 2013 PDF download Advertisement SubjectsCell Biology/Structural Biology
Referência(s)