Transgenerational effect of drug-mediated inhibition of LSD1 on eye pigment expression in Drosophila

Drug Induced ◽

Abstract Background: The Drosophila melanogaster mutant white-mottled is a well-established model for position-effect variegation (PEV). Transposition of the euchromatic white gene into the vicinity of the pericentric heterochromatin caused variegated expression of white due to heterochromatin spreading. The establishment of the euchromatin-heterochromatin boundary and spreading of silencing is regulated by mutually exclusive histone modifications, i.e. the methylations of histone H3 at lysine 9 and lysine 4. Demethylation of H3K4, catalysed by lysine-specific demethylase LSD1, is required for subsequent methylation of H3K9 to establish heterochromatin. LSD1 is therefore essential for heterochromatin formation and spreading. We asked whether drug-mediated inhibition of LSD affects the expression of white and if this induced change can be transmitted to those generations that have never been exposed to the triggering signal, i.e. transgenerational epigenetic inheritance.Results: We used the lysine-specific demethylase 1 (LSD1)-inhibitor Tranylcypromine to investigate its effect on eye colour expression in consecutive generations by feeding the parental and F1 generations of the Drosophila melanogaster mutant white-mottled. Quantitative Western blotting revealed that Tranylcypromine inhibits H3K4-demethylation both in vitro in S2 cells as well as in embryos when used as feeding additive. Eye colour expression in male flies was determined by optical measurement of pigment extracts and qRT-PCR of white gene expression. Flies raised in the presence of Tranylcypromine and its solvent DMSO showed increased eye pigment expression. Beyond that, eye pigment expression was also affected in consecutive generations including F3, which is the first generation without contact with the inhibitor.Conclusions: Our results show that feeding of Tranylcypromine and DMSO caused desilencing of white in treated flies of generation F1. Consecutive generations, raised on standard food without further supplements, are also affected by the drug-induced alteration of histone modifications. Although eye pigment expression eventually returned to the basal state, the observed long-lasting effect points to a memory capacity of previous epigenomes. Furthermore, our results indicate that food compounds potentially affect chromatin modification and hence gene expression and that the alteration is putatively inherited not only parentally but transgenerationally.

Transgenerational effect of drug-mediated inhibition of LSD1 on eye pigment expression in Drosophila

BMC Ecology ◽

10.1186/s12898-020-00330-6 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Sigrid Hoyer-Fender

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Histone Modifications ◽

Optical Measurement ◽

Position Effect ◽

Drug Induced ◽

Abstract Background The Drosophila melanogaster mutant white-mottled is a well-established model for position-effect variegation (PEV). Transposition of the euchromatic white gene into the vicinity of the pericentric heterochromatin caused variegated expression of white due to heterochromatin spreading. The establishment of the euchromatin-heterochromatin boundary and spreading of silencing is regulated by mutually exclusive histone modifications, i.e. the methylations of histone H3 at lysine 9 and lysine 4. Demethylation of H3K4, catalysed by lysine-specific demethylase LSD1, is required for subsequent methylation of H3K9 to establish heterochromatin. LSD1 is therefore essential for heterochromatin formation and spreading. We asked whether drug-mediated inhibition of LSD affects the expression of white and if this induced change can be transmitted to those generations that have never been exposed to the triggering signal, i.e. transgenerational epigenetic inheritance. Results We used the lysine-specific demethylase 1 (LSD1)-inhibitor Tranylcypromine to investigate its effect on eye colour expression in consecutive generations by feeding the parental and F1 generations of the Drosophila melanogaster mutant white-mottled. Quantitative Western blotting revealed that Tranylcypromine inhibits H3K4-demethylation both in vitro in S2 cells as well as in embryos when used as feeding additive. Eye colour expression in male flies was determined by optical measurement of pigment extracts and qRT-PCR of white gene expression. Flies raised in the presence of Tranylcypromine and its solvent DMSO showed increased eye pigment expression. Beyond that, eye pigment expression was also affected in consecutive generations including F3, which is the first generation without contact with the inhibitor. Conclusions Our results show that feeding of Tranylcypromine and DMSO caused desilencing of white in treated flies of generation F1. Consecutive generations, raised on standard food without further supplements, are also affected by the drug-induced alteration of histone modifications. Although eye pigment expression eventually returned to the basal state, the observed long-lasting effect points to a memory capacity of previous epigenomes. Furthermore, our results indicate that food compounds potentially affect chromatin modification and hence gene expression and that the alteration is putatively inherited not only parentally but transgenerationally.

Transgenerational effect of drug-mediated inhibition of LSD1 on eye pigment expression in Drosophila

10.21203/rs.3.rs-25657/v2 ◽

2020 ◽

Author(s):

Sigrid Hoyer-Fender

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Histone Modifications ◽

Optical Measurement ◽

Position Effect ◽

Drug Induced ◽

Abstract Background: The Drosophila melanogaster mutant white-mottled is a well-established model for position-effect variegation (PEV). Transposition of the euchromatic white gene into the vicinity of the pericentric heterochromatin caused variegated expression of white due to heterochromatin spreading. The establishment of the euchromatin-heterochromatin boundary and spreading of silencing is regulated by mutually exclusive histone modifications, i.e. the methylations of histone H3 at lysine 9 and lysine 4. Demethylation of H3K4, catalysed by lysine-specific demethylase LSD1, is required for subsequent methylation of H3K9 to establish heterochromatin. LSD1 is therefore essential for heterochromatin formation and spreading. We asked whether drug-mediated inhibition of LSD affects the expression of white and if this induced change can be transmitted to those generations that have never been exposed to the triggering signal, i.e. transgenerational epigenetic inheritance.Results: We used the lysine-specific demethylase 1 (LSD1)-inhibitor Tranylcypromine to investigate its effect on eye colour expression in consecutive generations by feeding the parental and F1 generations of the Drosophila melanogaster mutant white-mottled. Quantitative Western blotting revealed that Tranylcypromine inhibits H3K4-demethylation both in vitro in S2 cells as well as in embryos when used as feeding additive. Eye colour expression in male flies was determined by optical measurement of pigment extracts and qRT-PCR of white gene expression. Flies raised in the presence of Tranylcypromine and its solvent DMSO showed increased eye pigment expression. Beyond that, eye pigment expression was also affected in consecutive generations including F3, which is the first generation without contact with the inhibitor. Conclusions: Our results show that feeding of Tranylcypromine and DMSO caused desilencing of white in treated flies of generation F1. Consecutive generations, raised on standard food without further supplements, are also affected by the drug-induced alteration of histone modifications. Although eye pigment expression eventually returned to the basal state, the observed long-lasting effect points to a memory capacity of previous epigenomes. Furthermore, our results indicate that food compounds potentially affect chromatin modification and hence gene expression and that the alteration is putatively inherited not only parentally but transgenerationally.

Transgenerational effect of drug-mediated inhibition of LSD1 on eye pigment expression in Drosophila

10.21203/rs.3.rs-25657/v1 ◽

2020 ◽

Author(s):

Sigrid Hoyer-Fender

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Histone Modifications ◽

Optical Measurement ◽

Position Effect ◽

White Gene ◽

Drug Induced ◽

Abstract Background: The Drosophila melanogaster mutant white-mottled is a well-established model for position-effect variegation (PEV). Transposition of the euchromatic white gene into the vicinity of the pericentric heterochromatin caused variegated expression of white due to heterochromatin spreading. The establishment of the euchromatin-heterochromatin boundary and spreading of silencing is regulated by mutually exclusive histone modifications, i.e. the methylations of histone H3 at lysine 9 and lysine 4. Demethylation of H3K4, catalysed by lysine-specific demethylase LSD1, is required for subsequent methylation of H3K9 to establish heterochromatin. LSD1 is therefore essential for heterochromatin formation and spreading. We asked, whether drug-mediated inhibition of LSD affects expression of white and if this induced change can be transmitted to those generations that have never been exposed to the triggering signal, i.e. transgenerational epigenetic inheritance.Results: We used the lysine-specific demethylase 1 (LSD1)-inhibitor Tranylcypromine to investigate its effect on eye colour expression in consecutive generations by feeding the parental and F1 generations of the Drosophila melanogaster mutant white-mottled . Quantitative Western blotting revealed that Tranylcypromine inhibits H3K4-demethylation both in vitro in S2 cells as well as in embryos when used as feeding additive. Eye colour expression in male flies was determined by optical measurement of pigment extracts and qRT-PCR of white gene expression. Flies raised in the presence of Tranylcypromine and its solvent DMSO showed increased eye pigment expression. Beyond that, eye pigment expression was also affected in consecutive generations including F3, which is the first generation without contact to the inhibitor.Conclusions: Our results show that feeding of Tranylcypromine and DMSO caused desilencing of white in treated flies of generation F1. Consecutive generations, raised on standard food without further supplements, are also affected by the drug-induced alteration of histone modifications. Although eye pigment expression eventually returned to the basal state, the observed long-lasting effect points to a memory capacity of previous epigenomes. Furthermore, our results indicate that food compounds potentially affect chromatin modification and hence gene expression, and that the alteration is putatively inherited not only parentally but transgenerationally.

Evidence for intrinsic differences in the formation of chromatin domains in Drosophila melanogaster.

Genetics ◽

10.1093/genetics/132.4.1063 ◽

1992 ◽

Vol 132 (4) ◽

pp. 1063-1069 ◽

Cited By ~ 1

Author(s):

C P Bishop

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Genetic Background ◽

Position Effect ◽

The Other ◽

Compaction Process ◽

Chromatin Domains ◽

Effect Variegation ◽

Reporter Systems

Abstract The results of an investigation into intrinsic differences in the formation of two different heterochromatic domains are presented. The study utilized two different position effect variegation mutants in Drosophila melanogaster for investigating the process of compacting different stretches of DNA into heterochromatin. Each stretch of DNA encodes for a gene that affects different aspects of bristle morphology. The expression of each gene is prevented when it is compacted into heterochromatin thus the genes serve as effective reporter systems to monitor the spread of heterochromatin. Both variegating mutants are scored in the same cell such that environmental and genetic background differences are unambiguously eliminated. Any differences observed in the repression of the two genes must therefore be the result of intrinsic differences in the heterochromatic compaction process for the two stretches of DNA. Studies of the effects different enhancers of variegation have upon the compaction of the two genes indicate each compaction event occurs independently of the other, and that different components are involved in the two processes. These results are discussed with regard to spreading heterochromatin and the role this process may play in regulating gene expression.

Genetic factors controlling white gene expression of the transposon AR4-24 at a telomere in Drosophila melanogaster

Genome ◽

10.1139/g02-074 ◽

2002 ◽

Vol 45 (6) ◽

pp. 1025-1034 ◽

Cited By ~ 2

Author(s):

M L Balasov

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Y Chromosome ◽

Genetic Factors ◽

Position Effect ◽

Heterochromatin Protein 1 ◽

Heterochromatin Protein ◽

Effect Variegation ◽

Restricted Pattern

The position effect of the AR 4-24 P[white, rosy] transposon was studied at cytological position 60F. Three copies of the transposon (within ~50-kb region) resulted in a spatially restricted pattern of white variegation. This pattern was modified by temperature and by removal of the Y chromosome, suggesting that it was due to classical heterochromatin-induced position effect variegation (PEV). In contrast with classical PEV, extra dose of the heterochromatin protein 1 (HP1) suppressed white variegation and one dose enhanced it. The effect of Pc-G, trx-G, and other PEV suppressors was also tested. It was found that E(Pc)1, TrlR85, and mutations of Su(z)2C relieve AR 4-24- silencing and z1 enhances it. To explain the results obtained with these modifiers, it is proposed that PEV and telomeric position effect can counteract each other at this particular cytological site.Key words: position effect variegation, heterochromatin protein 1, Drosophila melanogaster.

Weakener of white (Wow), a gene that modifies the expression of the white eye color locus and that suppresses position effect variegation in Drosophila melanogaster.

Genetics ◽

10.1093/genetics/137.4.1057 ◽

1994 ◽

Vol 137 (4) ◽

pp. 1057-1070 ◽

Cited By ~ 1

Author(s):

J A Birchler ◽

U Bhadra ◽

L Rabinow ◽

R Linsk ◽

A T Nguyen-Huynh

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Position Effect ◽

Northern Analysis ◽

Regulatory Sequences ◽

Eye Color ◽

Effect Variegation ◽

Modifying Effect ◽

Color Gene

Abstract A locus is described in Drosophila melanogaster that modifies the expression of the white eye color gene. This trans-acting modifier reduces the expression of the white gene in the eye, but elevates the expression in other adult tissues. Because of the eye phenotype in which the expression of white is lessened but not eliminated, the newly described locus is called the Weakener of white (Wow). Northern analysis reveals that Wow can exert an inverse or direct modifying effect depending upon the developmental stage. Two related genes, brown and scarlet, that are coordinately expressed with white, are also affected by Wow. In addition, Wow modulates the steady state RNA level of the retrotransposon, copia. When tested with a white promoter-Alcohol dehydrogenase reporter. Wow confers the modifying effect to the reporter, suggesting a requirement of the white regulatory sequences for mediating the response. In addition to being a dosage sensitive regulator of white, brown, scarlet and copia, Wow acts as a suppressor of position effect variegation. There are many dosage sensitive suppressors of position effect variegation and many dosage-sensitive modifiers of gene expression. The Wow mutations provide evidence for an overlap between the two types of modifiers.

MATERNAL-ZYGOTIC LETHAL INTERACTIONS IN DROSOPHILA MELANOGASTER: THE EFFECTS OF DEFICIENCIES IN THE ZESTE-WHITE REGION OF THE X CHROMOSOME

Genetics ◽

10.1093/genetics/96.1.187 ◽

1980 ◽

Vol 96 (1) ◽

pp. 187-200 ◽

Cited By ~ 1

Author(s):

Leonard G Robbins

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

X Chromosome ◽

Position Effect ◽

Gene Activity ◽

White Region ◽

Effect Variegation ◽

Zygotic Gene ◽

Maternal Gene

ABSTRACT The possibility that essential loci in the zeste-white region of the Drosophila melanogaster X chromosome are expressed both maternally and zygotically has been tested. Maternal gene activity was varied by altering gene dose, and zygotic gene activity was manipulated by use of position-effect variegation of a duplication. Viability is affected when both maternal and zygotic gene activity are reduced, but not when either maternal or zygotic gene activity is normal. Tests of a set of overlapping deficiencies demonstrate that at least three sections of the zeste-white region yield maternal zygotic lethal interactions. Single-cistron mutations at two loci in one of these segments have been tested, and maternal heterozygosity for mutations at both loci give lethal responses of mutant-duplication zygotes. Thus, at least four of the 13 essential functions coded in the zeste-white region are active both maternally and zygotically, suggesting that a substantial fraction of the genome may function at both stages. The normal survival of zygotes when either maternal gene expression or zygotic gene expression is normal, and their inviability when both are depressed, suggests that a developmental stage exists when maternally determined functions and zygotically coded functions are both in use.

Mutational Analysis of a Histone Deacetylase in Drosophila melanogaster: Missense Mutations Suppress Gene Silencing Associated With Position Effect Variegation

Genetics ◽

10.1093/genetics/154.2.657 ◽

2000 ◽

Vol 154 (2) ◽

pp. 657-668 ◽

Cited By ~ 2

Author(s):

Randy Mottus ◽

Richard E Sobel ◽

Thomas A Grigliatti

Keyword(s):

Drosophila Melanogaster ◽

Histone Deacetylase ◽

Transcriptional Activity ◽

Mutational Analysis ◽

Position Effect ◽

Transcriptional Regulator ◽

Missense Mutations ◽

Effect Variegation ◽

New Mutations

Abstract For many years it has been noted that there is a correlation between acetylation of histones and an increase in transcriptional activity. One prediction, based on this correlation, is that hypomorphic or null mutations in histone deacetylase genes should lead to increased levels of histone acetylation and result in increased levels of transcription. It was therefore surprising when it was reported, in both yeast and fruit flies, that mutations that reduced or eliminated a histone deacetylase resulted in transcriptional silencing of genes subject to telomeric and heterochromatic position effect variegation (PEV). Here we report the first mutational analysis of a histone deacetylase in a multicellular eukaryote by examining six new mutations in HDAC1 of Drosophila melanogaster. We observed a suite of phenotypes accompanying the mutations consistent with the notion that HDAC1 acts as a global transcriptional regulator. However, in contrast to recent findings, here we report that specific missense mutations in the structural gene of HDAC1 suppress the silencing of genes subject to PEV. We propose that the missense mutations reported here are acting as antimorphic mutations that “poison” the deacetylase complex and propose a model that accounts for the various phenotypes associated with lesions in the deacetylase locus.

Competition Between Different Variegating Rearrangements for Limited Heterochromatic Factors in Drosophila melanogaster

Genetics ◽

10.1093/genetics/145.4.945 ◽

1997 ◽

Vol 145 (4) ◽

pp. 945-959

Author(s):

Vett K Lloyd ◽

Donald A Sinclair ◽

Thomas A Grigliatti

Keyword(s):

Drosophila Melanogaster ◽

Chromosome Rearrangement ◽

Position Effect ◽

Euchromatic Region ◽

Single Chromosome ◽

Mosaic Expression ◽

Effect Variegation ◽

Protein Components

Position effect variegation (PEV) results from the juxtaposition of a euchromatic gene to heterochromatin. In its new position the gene is inactivated in some cells and not in others. This mosaic expression is consistent with variability in the spread of heterochromatin from cell to cell. As many components of heterochromatin are likely to be produced in limited amounts, the spread of heterochromatin into a normally euchromatic region should be accompanied by a concomitant loss or redistribution of the protein components from other heterochromatic regions. We have shown that this is the case by simultaneously monitoring variegation of a euchromatic and a heterochromatic gene associated with a single chromosome rearrangement. Secondly, if several heterochromatic regions of the genome share limited components of heterochromatin, then some variegating rearrangements should compete for these components. We have examined this hypothesis by testing flies with combinations of two or more different variegating rearrangements. Of the nine combinations of pairs of variegating rearrangements we studied, seven showed nonreciprocal interactions. These results imply that many components of heterochromatin are both shared and present in limited amounts and that they can transfer between chromosomal sites. Consequently, even nonvariegation portions of the genome will be disrupted by re-allocation of heterochromatic proteins associated with PEV. These results have implications for models of PEV.

Interactions Among Dosage-Dependent Trans-Acting Modifiers of Gene Expression and Position-Effect Variegation in Drosophila

Genetics ◽

10.1093/genetics/150.1.251 ◽

1998 ◽

Vol 150 (1) ◽

pp. 251-263 ◽

Cited By ~ 3

Author(s):

Utpal Bhadra ◽

Manika Pal Bhadra ◽

James A Birchler

Keyword(s):

Gene Expression ◽

Quantitative Traits ◽

Position Effect ◽

Developmental Transitions ◽

Eye Color ◽

Dosage Effects ◽

Effect Variegation ◽

Hierarchical Manner ◽

Color Gene

Abstract We have investigated the effect of dosage-dependent trans-acting regulators of the white eye color gene in combinations to understand their interaction properties. The consequences of the interactions will aid in an understanding of aneuploid syndromes, position-effect variegation (PEV), quantitative traits, and dosage compensation, all of which are affected by dosage-dependent modifiers. Various combinations modulate two functionally related transcripts, white and scarlet, differently. The overall trend is that multiple modifiers are noncumulative or epistatic to each other. In some combinations, developmental transitions from larvae to pupae to adults act as a switch for whether the effect is positive or negative. With position-effect variegation, similar responses were found as with gene expression. The highly multigenic nature of dosage-sensitive modulation of both gene expression and PEV suggests that dosage effects can be progressively transduced through a series of steps in a hierarchical manner.