caa a22 4500 60619066X CHVBK 20210128100856.0 cr unu---uuuuu 210128e20151201xx s 000 0 eng 10.1007/s10577-015-9497-1 doi (NATIONALLICENCE)springer-10.1007/s10577-015-9497-1 Unusual chromatin state in Rhynchosciara americana (Diptera: Sciaridae) [Elektronische Daten] [Alejandra Badaracco, Eduardo Gorab] Euchromatin and heterochromatin are usually defined by the degree of DNA compaction, gene content and combinations of histone and non-histone proteins. More recent studies on protein location have been able to specify a variety of chromatin types thus adding chromatin configurations other than the two basic reference states. Chromatin research exploiting non-model organisms has the potential to provide novel information related to epigenetic modifications and their impact on chromosome structure and function. Polytene chromosomes of Rhynchosciara americana display a particular region within the A9 sub-section characterised by lack of DNA compaction as well as an usual polytene banding pattern. DNA content in the sub-section seems to be low as deduced by DAPI staining. Antibodies to H3K4me, a conserved epigenetic transcription marker, labelled the A9 sub-section strongly. In contrast, transcriptional activity in the region, if any, seems to be low as inferred by detection of RNA polymerase II and RNA. Histone markers related to heterochromatin formation such as H3K9me and H3K27me are underrepresented in the A9 sub-section. However, a chromodomain-containing sciarid protein was detected in the region, displaying levels of fluorescence very close to those observed in pericentric heterochromatin. A plasmid micro-library constructed with micro-dissected DNA from the A9 sub-section was screened for repetitive DNA. The proportion of inserts containing repeats was found to be similar to that contained in another micro-library made with DNA from a single chromosome end of this species. The data suggest an unusual "chromatin colour” indicating that high levels of histone markers related to transcription coexist with a significant presence of chromodomain-containing proteins and the virtual absence of histone modifications observed in heterochromatin formation. Springer Science+Business Media Dordrecht, 2015 chromatin nationallicence chromodomain nationallicence Diptera nationallicence Heterochromatin nationallicence histones nationallicence Rhynchosciara nationallicence CCD : Charged coupled device nationallicence DAPI : 4′,6-diamidino-2-phenylindole nationallicence DOP-PCR : Degenerate oligonucleotide primed PCR nationallicence dNTP : Deoxy-ribonucleotide 5′-triphosphate nationallicence dUTP : 2′-deoxy-uridine 5′-triphosphate nationallicence FITC : Fluorescein isothiocyanate nationallicence H3K27ac : Histone H3 acetylated at lysine 27 nationallicence H3K4me2 : Histone H3 dimethylated at lysine 4 nationallicence H3K4me3 : Histone H3 trimethylated at lysine 4 nationallicence H3K9me1 : Histone H3 monomethylated at lysine 9 nationallicence H3K9me2 : Histone H3 dimethylated at lysine 9 nationallicence H3K9me3 : Histone H3 trimethylated at lysine 9 nationallicence H3K27me1 : Histone H3 monomethylated at lysine 27 nationallicence H3K27me2 : Histone H3 dimethylated at lysine 27 nationallicence H3K27me3 : Histone H3 trimethylated at lysine 27 nationallicence IgG : Immunoglobulin nationallicence Kbp : Kilobase pairs nationallicence PCR : Polymerase chain reaction nationallicence SDS : Sodium dodecyl sulfate nationallicence SSC : Sodium saline citrate nationallicence TBS : Tris-buffered saline nationallicence TBST : Tris buffered saline, 0.1% Triton X-100 nationallicence TRITC : Tetramethyl rhodamine isothiocyanate nationallicence Badaracco Alejandra Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, Cidade Universitária, CEP: 05508-090, São Paulo, SP, Brazil aut Gorab Eduardo Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, Cidade Universitária, CEP: 05508-090, São Paulo, SP, Brazil aut Chromosome Research Springer Netherlands 23/4(2015-12-01), 781-790 0967-3849 23:4<781 2015 23 10577 https://doi.org/10.1007/s10577-015-9497-1 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10577-015-9497-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Badaracco Alejandra Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, Cidade Universitária, CEP: 05508-090, São Paulo, SP, Brazil aut NATIONALLICENCE 700 1- Gorab Eduardo Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, Rua do Matão 277, Cidade Universitária, CEP: 05508-090, São Paulo, SP, Brazil aut NATIONALLICENCE 773 0- Chromosome Research Springer Netherlands 23/4(2015-12-01), 781-790 0967-3849 23:4<781 2015 23 10577