title: Heterochromatic silencing and HP1 localization in Drosophila are dependent on the RNAi machinery.
abstract: Genes normally resident in euchromatic domains are silenced when packaged into heterochromatin, as exemplified in Drosophila melanogaster by position effect variegation (PEV). Loss-of-function mutations resulting in suppression of PEV have identified critical components of heterochromatin, including proteins HP1, HP2, and histone H3 lysine 9 methyltransferase. Here, we demonstrate that this silencing is dependent on the RNA interference machinery, using tandem mini-white arrays and white transgenes in heterochromatin to show loss of silencing as a result of mutations in piwi, aubergine, or spindle-E (homeless), which encode RNAi components. These mutations result in reduction of H3 Lys9 methylation and delocalization of HP1 and HP2, most dramatically in spindle-E mutants.
authors.affiliation: Division of Biological Sciences, 117 Tucker Hall, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Manika
authors.initials: M
authors.lastname: Pal-Bhadra
authors.forename: Boris A
authors.initials: BA
authors.lastname: Leibovitch
authors.forename: Sumit G
authors.initials: SG
authors.lastname: Gandhi
authors.forename: Madhusudana Rao
authors.initials: MR
authors.lastname: Chikka
authors.forename: Madhusudana
authors.initials: M
authors.lastname: Rao
authors.forename: Utpal
authors.initials: U
authors.lastname: Bhadra
authors.forename: James A
authors.initials: JA
authors.lastname: Birchler
authors.forename: Sarah C R
authors.initials: SC
authors.lastname: Elgin
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000502:physiology; D000251:Adenosine Triphosphatases / Q000235:genetics / Q000502:physiology; D000483:Alleles; D000818:Animals; D060565:Argonaute Proteins; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics / Q000502:physiology; D020868:Gene Silencing; D017344:Genes, Insect; D006570:Heterochromatin / Q000378:metabolism*; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D008745:Methylation; D009154:Mutation; D011506:Proteins / Q000235:genetics / Q000502:physiology; D034622:RNA Interference; D034743:RNA-Induced Silencing Complex; D019076:Transgenes
chemical_list: D018528:ATP-Binding Cassette Transporters; D060565:Argonaute Proteins; D002868:Chromosomal Proteins, Non-Histone; D029721:Drosophila Proteins; D005136:Eye Proteins; D006570:Heterochromatin; D006657:Histones; D011506:Proteins; D034743:RNA-Induced Silencing Complex; C452193:heterochromatin protein 1, Drosophila; C116498:piwi protein, Drosophila; C059254:w protein, Drosophila; D011495:Histone-Lysine N-Methyltransferase; D000251:Adenosine Triphosphatases; C096355:spn-E protein, Drosophila