Human Histone Demethylase LSD1 Reads the Histone Code

Abstract

Human histone demethylase LSD1 is a flavin-dependent amine oxidase that catalyzes the specific removal of methyl groups from mono- and dimethylated Lys4 of histone H3. The N-terminal tail of H3 is subject to various covalent modifications, and a fundamental question in LSD1 biology is how these epigenetic marks affect the demethylase activity. We show that LSD1 does not have a strong preference for mono- or dimethylated Lys4 of H3. Substrate recognition is not confined to the residues neighboring Lys4, but it requires a sufficiently long peptide segment consisting of the N-terminal 20 amino acids of H3. Electrostatic interactions are an important factor in protein-substrate recognition, as indicated by the high sensitivity of Km to ionic strength. We have probed LSD1 for its ability to demethylate Lys4 in presence of a second modification on the same peptide substrate. Methylation of Lys9 does not affect enzyme catalysis. Conversely, Lys9 acetylation causes an almost 6-fold increase in the Km value, whereas phosphorylation of Ser10 totally abolishes activity. LSD1 is inhibited by a demethylated peptide with an inhibition constant of 1.8 μm, suggesting that LSD1 can bind to H3 independently of Lys4 methylation. LSD1 is a chromatin-modifying enzyme, which is able to read different epigenetic marks on the histone N-terminal tail and can serve as a docking module for the stabilization of the associated corepressor complex(es) on chromatin. Human histone demethylase LSD1 is a flavin-dependent amine oxidase that catalyzes the specific removal of methyl groups from mono- and dimethylated Lys4 of histone H3. The N-terminal tail of H3 is subject to various covalent modifications, and a fundamental question in LSD1 biology is how these epigenetic marks affect the demethylase activity. We show that LSD1 does not have a strong preference for mono- or dimethylated Lys4 of H3. Substrate recognition is not confined to the residues neighboring Lys4, but it requires a sufficiently long peptide segment consisting of the N-terminal 20 amino acids of H3. Electrostatic interactions are an important factor in protein-substrate recognition, as indicated by the high sensitivity of Km to ionic strength. We have probed LSD1 for its ability to demethylate Lys4 in presence of a second modification on the same peptide substrate. Methylation of Lys9 does not affect enzyme catalysis. Conversely, Lys9 acetylation causes an almost 6-fold increase in the Km value, whereas phosphorylation of Ser10 totally abolishes activity. LSD1 is inhibited by a demethylated peptide with an inhibition constant of 1.8 μm, suggesting that LSD1 can bind to H3 independently of Lys4 methylation. LSD1 is a chromatin-modifying enzyme, which is able to read different epigenetic marks on the histone N-terminal tail and can serve as a docking module for the stabilization of the associated corepressor complex(es) on chromatin. Histones play a fundamental role in the control of a variety of cellular processes, including gene expression, DNA replication, and repair. Histone function is modulated through covalent modifications by acetylation, methylation, ubiquitination, and sumoylation (1Biel M. Wascholowski V. Giannis A. Angew. Chem. Int. Ed. Engl. 2005; 44: 3186-3216Crossref PubMed Scopus (250) Google Scholar, 2Fischle W. Wang Y. Allis C.D. Nature. 2003; 425: 475-479Crossref PubMed Scopus (551) Google Scholar). These modifications have specific effects and act in a combinatorial manner defining the so-called histone code (1Biel M. Wascholowski V. Giannis A. Angew. Chem. Int. Ed. Engl. 2005; 44: 3186-3216Crossref PubMed Scopus (250) Google Scholar, 3Jenuwein T. Allis C.D. Science. 2001; 293: 1074-1080Crossref PubMed Scopus (7709) Google Scholar). Very recently, Shi et al. (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar) and our group (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar) have reported on the discovery of the first enzyme able to specifically demethylate Lys4 of histone H3. The protein was therefore named LSD1 (for lysine-specific demethylase; it is also known as KIAA0601 and BHC110). The existence of histone-demethylating enzymes has always been questioned (6Sims R.J. Nishioka K. Reinberg D. Trends Genet. 2003; 19: 629-639Abstract Full Text Full Text PDF PubMed Scopus (542) Google Scholar, 7Bannister A.J. Kouzarides T. Nature. 2005; 436: 1103-1106Crossref PubMed Scopus (396) Google Scholar), and with the discovery of LSD1, it was firmly established that histone methylation is a dynamic process under enzymatic control similar to the other known post-translational histone modifications. LSD1 has been typically found in association with CoREST and HDAC1/2 proteins, forming a module found in several multiprotein co-repressor complexes (8Humphrey G.W. Wang Y. Russanova V.R. Hirai T. Qin J. Nakatani Y. Howard B.H. J. Biol. Chem. 2001; 276: 6817-6824Abstract Full Text Full Text PDF PubMed Scopus (268) Google Scholar, 9Ballas N. Battaglioli E. Atouf F. Andres M.E. Chenoweth J. Anderson M.E. Burger C. Moniwa M. Davie J.R. Bowers W.J. Federoff H.J. Rose D.W. Rosenfeld M.G. Brehm P. Mandel G. Neuron. 2001; 31: 353-365Abstract Full Text Full Text PDF PubMed Scopus (355) Google Scholar, 10Shi Y. Sawada J. Sui G. Affar B. Whetstine J.R. Lan F. Ogawa H. Luke M.P. Nakatani Y. Shi Y. Nature. 2003; 422: 735-738Crossref PubMed Scopus (644) Google Scholar, 11Shi Y.J. Matson C. Lan F. Iwase S. Baba T. Shi Y. Mol. Cell. 2005; 19: 857-864Abstract Full Text Full Text PDF PubMed Scopus (668) Google Scholar). Knock-out of LSD1 by RNA interference was shown to cause increased levels of histone methylation, resulting in the reactivation of a specific target gene (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar). It has also been shown that LSD1 is a bona fide co-repressor able to repress a reporter gene and that this function is dependent on the demethylase activity (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar). Based on sequence homology analysis, it was predicted that several histone demethylases are likely to exist in mammalian and other eukaryotic organisms (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar). From a biochemical and structural standpoint, LSD1 belongs to the class of flavin-dependent amine oxidases, which typically catalyze the oxidation of an amine-containing substrate using molecular oxygen as the electron acceptor (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar, 12Binda C. Mattevi A. Edmondson D.E. J. Biol. Chem. 2002; 277: 23973-23976Abstract Full Text Full Text PDF PubMed Scopus (152) Google Scholar). Indeed, LSD1 catalyzes the demethylase reaction through an oxidative process (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar) (Fig. 1a). The amino group of the methylated Lys is oxidized presumably to generate the corresponding imine compound, which is subsequently hydrolyzed to produce formaldehyde. Substrate oxidation leads to the two-electron reduction of the protein-bound FAD cofactor, which is regenerated to its oxidized form by molecular oxygen to produce hydrogen peroxide. LSD1 catalyzes the specific removal of methyl groups from mono- and dimethylated Lys4 of histone H3 (H3-K4) 5The abbreviations used are: H3-K4Lys4 of histone 3H3histone 3Δ184human LSD1 mutant harboring a deletion of the N-terminal 184 amino acidsMes2-(N-morpholinoethanesulfonic acidTaps3-{[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]amino}-1-propanesulfonic acid. (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar, 5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar), although an androgen receptor-controlled activity on H3-K9 has also been reported (13Metzger E. Wissmann M. Yin N. Muller J.M. Schneider R. Peters A.H. Gunther T. Buettner R. Schule R. Nature. 2005; 437: 436-439Crossref PubMed Scopus (1378) Google Scholar). The histone H3 N-terminal tail is a region characterized by extreme density of covalent modifications with diverse biological meanings (reviewed in Refs. 1Biel M. Wascholowski V. Giannis A. Angew. Chem. Int. Ed. Engl. 2005; 44: 3186-3216Crossref PubMed Scopus (250) Google Scholar, 2Fischle W. Wang Y. Allis C.D. Nature. 2003; 425: 475-479Crossref PubMed Scopus (551) Google Scholar, and 6Sims R.J. Nishioka K. Reinberg D. Trends Genet. 2003; 19: 629-639Abstract Full Text Full Text PDF PubMed Scopus (542) Google Scholar). Among them, of special significance are positions Lys4, Lys9, and Ser10, which are the most extensively and widely studied epigenetic marks of H3. Methylation of Lys4 is generally known to activate transcription, and, therefore, the demethylase activity of LSD1 removes an activation mark. Lys9 can be either acetylated or methylated, resulting in opposite effects; acetylation promotes formation of euchromatin, whereas methylation leads to repression of transcription. Phosphorylation of Ser10 is a pivotal activating signal and prevents the recruitment of the transcriptional repressors by methylated Lys9. A key problem is now to define the biological properties of LSD1, especially in relation to its ability to “read and interpret” these epigenetic marks on H3. We addressed this problem through an in vitro study that probed human LSD1 (Fig. 2a) for its ability to act on histone peptides bearing different covalent modifications. Lys4 of histone 3 histone 3 human LSD1 mutant harboring a deletion of the N-terminal 184 amino acids 2-(N-morpholinoethanesulfonic acid 3-{[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]amino}-1-propanesulfonic acid. Protein Purification—Escherichia coli cells overproducing a truncated form of LSD1 lacking the N-terminal 184 amino acids (Δ184) were grown as described (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar). The recombinant protein was purified following the protocol of Forneris et al. (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar), modified by omitting the cation exchange chromatography step. The purity of the protein was monitored by SDS-PAGE (Fig. 2a) and UV-visible absorption spectroscopy. The recombinant protein carries an N-terminal His6 tag to facilitate purification. Control experiments have shown that removal of the His6 tag by proteolysis (using TEV protease) did not alter the enzyme activity by more than 5%. Protein aliquots were stored in 50 mm sodium phosphate buffer, pH 7.5, and 50% (w/v) glycerol at -80 °C. Protein concentrations were routinely measured by absorption spectroscopy using an extinction coefficient of 10,790 m-1 cm-1 at 458 nm, which was determined based on absorbance changes observed after protein denaturation in 50 mm sodium phosphate buffer, pH 7.5, plus 0.3% (w/v) SDS (14Aliverti A. Curti B. Vanoni M.A. Methods Mol. Biol. 1999; 131: 9-23PubMed Google Scholar). Activity Assays—Peptides were purchased from Thermo Electron Corp. Their purity was greater than 90% as checked by analytical high pressure liquid chromatography and mass spectrometry. All other chemicals were from Sigma. Initial velocity measurements were performed using a peroxidase-coupled assay, which monitors hydrogen peroxide production (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar). The time courses of the reaction were measured under aerobic conditions by using a Cary 100 UV-visible spectro-photometer equipped with thermostated cell holder (T were by of protein protein in 50 mm sodium phosphate buffer, pH 7.5, and (w/v) to reaction consisting of 50 mm buffer, pH 7.5, mm mm and concentrations of methylated changes were monitored at nm, and an extinction coefficient of m-1 cm-1 was used to the velocity of which were the velocity as were to the (Fig. using which the of and Km with associated of and pH on LSD1 the effects of ionic on LSD1 were performed by using of and in the reaction from mm to the of the pH of the pH was using at a of 50 The ionic was constant at mm by the of an of to We checked that the extinction coefficient of the by the reaction did not as a function of The and were to the following which that a at and high pH to a as groups with and were by using the peroxidase-coupled in the presence of concentrations of methylated peptides and of the under μm, on the Initial velocity were to and inhibition using the was with the a which to in the for a of the We have to peptide also by found that the of the the protein and this the of with and were performed using a recombinant truncated form of human LSD1 (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar) lacking the first 184 amino acids to the sequence in the with code amino protein form the and oxidase of LSD1 N. Battaglioli E. Atouf F. Andres M.E. Chenoweth J. Anderson M.E. Burger C. Moniwa M. Davie J.R. Bowers W.J. Federoff H.J. Rose D.W. Rosenfeld M.G. Brehm P. Mandel G. Neuron. 2001; 31: 353-365Abstract Full Text Full Text PDF PubMed Scopus (355) Google of the amino acid sequence by that the 184 truncated amino acids not an (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar). control experiments that the properties of are from of lacking the first and the the protein used by Shi et al. (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar). The mutant was it can be in E. coli cells and purified to a and form in the to the described experiments (Fig. LSD1 activity was monitored using histone which to the and and the effects of various covalent modifications. The first question addressed in our study was the in the mono- and dimethylated We performed using peptides consisting of the H3 N-terminal amino acids modified by mono- or of These were the peptides in the that to the discovery of LSD1 function (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar, 5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar). The using these to be similar and that LSD1 does not a strong preference for dimethylated substrate. of the enzymatic measured with the acid peptides was that a to the activity of LSD1 peptides of different or bearing covalent modifications of human were determined in mm pH 7.5, at by a peroxidase-coupled were determined in mm pH 7.5, at by a peroxidase-coupled were determined in mm pH 7.5, at by a peroxidase-coupled of was as described of activity with to that measured with of amino a the and Km for and peptides were measured also by of a with a acceptor that with the FAD The resulting were to measured with the peroxidase-coupled in was performed in mm 50 mm pH 7.5, at of different not The activity is or were determined in mm pH 7.5, at by a peroxidase-coupled (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google of was as described and for the The of activity with to that measured with a the and Km for and peptides were measured also by of a (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar), with a acceptor that with the FAD The resulting were to measured with the peroxidase-coupled The was performed in mm 50 mm pH 7.5, at not The activity is or in a The peptide substrate is in and groups N-terminal amino and Lys that in are of epigenetic marks (Fig. We have therefore the of pH and ionic on the enzymatic activity. and a pH at and high pH (Fig. The as a group with of and as a group with of a similar with of and The similar observed in the and that the of the same groups and that groups to the enzyme than to the peptide substrate Scholar). the be that the of observed in the the of of the or Lys residues of the substrate. the that the and at pH and the reported in this to performed at pH 7.5, which is of significance and to the pH for activity. A role of groups is also by the of the of the ionic on LSD1 The enzyme activity constant at or concentrations to 50 but it at concentrations that of activity is measured at concentrations greater than The observed of activity is to a Km as shown by the that at mm the Km is than that found in the of whereas the measured at and mm are this the specific activity reported for LSD1 (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar) can be to the ionic of the which were in 50 mm sodium phosphate buffer, pH as to 50 mm pH Substrate and define the peptide by LSD1, studied the ability of the enzyme to demethylate peptides consisting of the N-terminal and amino acids (Fig. and modified by of Lys4 and for the acid substrate were similar to measured with the acid Conversely, with the acid the activity and with peptides activity be at The of activity with these peptides was observed also at a pH of which is for (Fig. The of these experiments indicated that substrate recognition by LSD1 is not confined to the residues neighboring Lys4, but it requires a long peptide the substrate of the LSD1 is associated to the CoREST which has been shown to LSD1 activity of the Y.J. Matson C. Lan F. Iwase S. Baba T. Shi Y. Mol. Cell. 2005; 19: 857-864Abstract Full Text Full Text PDF PubMed Scopus (668) Google Scholar, M.G. C. N. R. Nature. 2005; 437: PubMed Scopus Google Scholar). CoREST this through stabilization of the with the substrate increase of the of the N-terminal that LSD1 a long H3 peptide segment the that the reaction the demethylated bind to the of this that the acid peptide is a with a of 1.8 with the substrate a acid peptide a reduction in deletion of the N-terminal residues from the acid peptide in a reduction of the These that methylation of Lys4 is not for whereas the is dependent on the presence of a sufficiently long segment of the H3 N-terminal of human LSD1 by histone H3 were in mm pH 7.5, at by a peroxidase-coupled using a acid peptide on Lys4 the inhibition was of the were in mm pH 7.5, at by a peroxidase-coupled using a acid peptide on Lys4 (5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar). the inhibition was of the in a et al. (13Metzger E. Wissmann M. Yin N. Muller J.M. Schneider R. Peters A.H. Gunther T. Buettner R. Schule R. Nature. 2005; 437: 436-439Crossref PubMed Scopus (1378) Google Scholar) have reported on an androgen activity of The with the to the substrate LSD1 able to demethylate Lys9 of H3 LSD1 does not act on (4Shi Y. Lan F. Matson C. Mulligan P. Whetstine J.R. Cole P.A. Casero R.A. Shi Y. Cell. 2004; 119: 941-953Abstract Full Text Full Text PDF PubMed Scopus (3215) Google Scholar, 5Forneris F. Binda C. Vanoni M.A. Mattevi A. Battaglioli E. FEBS Lett. 2005; 579: 2203-2207Crossref PubMed Scopus (221) Google Scholar). activity was shown to be inhibited by and which are specific of human oxidase A D.E. Mattevi A. Binda C. M. F. Chem. 2004; PubMed Scopus Google Scholar). We have these act on LSD1, with its demethylase inhibition was and, in of these the changes in the absorption of the protein-bound that are found in inhibited not of N-terminal tail of H3 is subject to various covalent modifications, and a question in LSD1 biology is how these epigenetic marks affect the demethylase activity. We have probed LSD1 for its ability to demethylate Lys4 in the presence of a second modification on the same acid peptide substrate. shown in the effects of methylation and acetylation of Lys9 and phosphorylation of Methylation of Lys9 did not affect whereas Lys9 acetylation an almost 6-fold increase in the Km value, that this covalent modification the substrate more is the of Ser10 which totally the ability of the peptide to function as substrate. these are with the that interactions are especially in the Methylation of Lys9, which does not the Lys has on enzymatic Conversely, of Lys9 by acetylation whereas of the phosphate group on Ser10 abolishes activity. These that the to a of hydrogen groups that LSD1 to the presence of various covalent modifications on this (Fig. A fundamental from these experiments is that LSD1 is of the histone code in that it peptides bearing different covalent modifications on to the that a the a and a found that the Ser10 peptide is a of the enzyme of that the peptide is able to bind to LSD1, but its is that it be other the phosphate group on Ser10 to the of the methylated Lys4 the (Fig. The from these is that LSD1 is and has for the control of histone H3 and its role in A first important is that LSD1 does not have a strong preference for mono- or dimethylated with the properties of that specifically the of the or methyl group on a Lys 2005; PubMed Scopus Google Scholar). The that LSD1 with similar on mono- and dimethylated that the in function of LSD1 is to to its demethylated We have shown that an H3 peptide the first N-terminal amino acids of H3 in to be a substrate. The sequence of this has and interactions are likely to the protein-substrate a for the high sensitivity of Km to ionic strength. ability of a and segment of the histone N-terminal tail LSD1 to the presence of post-translational modifications in the H3 tail (Fig. this several important properties have been LSD1 has an the of oxidative is Lys4, the enzyme covalent modifications on neighboring The on the histone N-terminal tail to be a key in the of the histone code by LSD1, as by the effects of methylation and acetylation of Lys9 on enzyme activity. The Lys4 demethylase activity of LSD1 is not by methylation of Lys9, which is generally known to cause gene Lys9 and Ser10 and act in the Lys4 Ser10 is a for LSD1 whereas Lys9 activity through an increase in substrate These the and of the that to transcriptional of Ser10 by a H3 by LSD1, the role of Ser10 in the of that to transcriptional Lys9 by HDAC1/2 are typically associated with H3 more to The activity of LSD1 can be modulated by its associated protein Y.J. Matson C. Lan F. Iwase S. Baba T. Shi Y. Mol. Cell. 2005; 19: 857-864Abstract Full Text Full Text PDF PubMed Scopus (668) Google Scholar, E. Wissmann M. Yin N. Muller J.M. Schneider R. Peters A.H. Gunther T. Buettner R. Schule R. Nature. 2005; 437: 436-439Crossref PubMed Scopus (1378) Google Scholar, M.G. C. N. R. Nature. 2005; 437: PubMed Scopus Google Scholar), and the enzyme observed on peptides be different and are used as it is of that the observed with a peptide acetylated on Lys9 is with the by Shi et al. Y.J. Matson C. Lan F. Iwase S. Baba T. Shi Y. Mol. Cell. 2005; 19: 857-864Abstract Full Text Full Text PDF PubMed Scopus (668) Google Scholar) that LSD1 is more LSD1 with to a demethylated H3 as indicated by an inhibition constant that with the Km for the peptide The measured is similar to the measured for other as the Y. J. Allis C.D. S. J. 2001; PubMed Scopus Google Scholar) and W. Wang Y. Y. Allis C.D. S. 2003; PubMed Scopus Google Scholar). the that LSD1 a that of demethylase and of H3 N-terminal tail LSD1 is of the co-repressor a module that has been found in association with several multiprotein The that LSD1 has for the H3 peptide that it serve as a docking module for the stabilization of the associated corepressor complex(es) on chromatin. in it has been that the CoREST corepressor to after the of the protein for its recruitment N. C. Mandel G. Cell. 2005; Full Text Full Text PDF PubMed Scopus Google Scholar). The from these is that LSD1 is not a chromatin-modifying enzyme, but it is able to histone marks on the and to the co-repressor by to the demethylated H3. of LSD1 substrate properties a for The of A. E. and G. Mandel is We N. for the